METGLAS 2605SA1 Fe-Si-B
Iron-based amorphous metal, Fe-Si-B ribbon: Fe 85 to 95, Si 5 to 10, B 1 to 5 (weight %, SDS ranges) · amorphous
Also known as 2605 SA1 Iron Base Alloy, 2605SA1
METGLAS 2605SA1 is an iron-based amorphous metal ribbon from Metglas, Inc., about 23 to 25 micrometres thick.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Saturation induction
1.56 T
Permeability
45,000 to 600,000
Shielding
57,000 after relaxation
Temperature
150 degC
Recipe, share of the weight
- Fe 85 to 95%Iron
- Si 5 to 10%Silicon
- B 1 to 5%Boron
- trace, not quantifiedCobalt and nickel
Best for
Low-loss transformer and current-transformer cores, where core loss of 0.17 W/kg or less at 60 Hz and 1.3 T is the target (datasheet limit)
Weakest at
Formability of the as-supplied ribbon, which the 2015 paper calls difficult because its yield strength appears extremely high; its permeability also takes about four days to reach maximum after a change in field
Risk at a glance
- People Low. Non-hazardous as shipped
- If it fails Moderate. Fire or melting of the ribbon
- Corrosion No data. No corrosion data recorded
Quick facts: Fe-Si-B
| Property | Value | Basis |
|---|---|---|
| Density | 7.18 to 7.19 g/cm³ | 2 sourced values across conditions |
| Tensile strength | 2,000 MPa | 1 sourced value |
| Young's modulus | 110 GPa | 1 sourced value |
| Thermal expansion (CTE) | 7.6 x10-6/degC | 1 sourced value |
| Melting point | 1,133 to 1,178 °C | 1 sourced value |
| Electrical resistivity | 0.0000013 Ω·m | 1 sourced value |
| Maximum service temperature | 150 °C | 1 sourced value |
What is the density of METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) has a density of 7.18 to 7.19 g/cm³. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the coefficient of thermal expansion of METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) has a coefficient of thermal expansion of 7.6 x10-6/degC. The source and test conditions are listed in the properties table on this page.
What is the melting point of METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) has a melting point of 1,133 to 1,178 °C. The source and test conditions are listed in the properties table on this page.
What is the tensile strength of METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) has a tensile strength of 2,000 MPa. The source and test conditions are listed in the properties table on this page.
What is the Young's modulus of METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) has a Young's modulus of 110 GPa. The source and test conditions are listed in the properties table on this page.
What are the other names and codes for METGLAS 2605SA1 (Fe-Si-B)?
METGLAS 2605SA1 (Fe-Si-B) is also written as 2605 SA1 Iron Base Alloy, 2605SA1. Each code is printed in the source listed beside it in the designations table.
What is METGLAS 2605SA1 (Fe-Si-B) used for?
Uses recorded in the sources include Distribution, commercial and industrial transformer cores; Magnetic shield for superconducting RF cavity cryomodules; Current transformers, high-frequency inductors and motors.
Why it exists
METGLAS 2605SA1 is an iron-based amorphous metal ribbon made by Metglas, Inc. Its atoms do not sit in a crystal lattice, so the ribbon has no grain boundaries, as a 2015 Fermilab paper explains. The manufacturer offers it for transformer cores, current transformers and high-frequency inductors. The same 2015 paper tested it as a magnetic shield for superconducting RF cavity cryomodules, which is the space-adjacent use in this profile.
Where it's used
Transformer cores
The manufacturer's datasheet lists 2605SA1 for single and three phase commercial, industrial and distribution transformers. The core loss limit is 0.17 W/kg at 60 Hz and 1.3 T.
Magnetic shield for superconducting RF cryomodules
A 2015 Fermilab paper says 2605SA1 is useful as a magnetic shield for certain superconducting RF cavity cryomodules. The authors measured its shielding of a steady field of about 5x10-5 T.
Recipe
Iron-based amorphous metal, Fe-Si-B ribbon: Fe 85 to 95, Si 5 to 10, B 1 to 5 (weight %, SDS ranges); trace cobalt and nickel
METGLAS 2605SA1 is a ribbon of iron with silicon and boron. The SDS gives weight ranges rather than a fixed formula. The ribbon is amorphous, so it has no crystal structure and no grain boundaries, as the 2015 paper notes.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Iron Fe | 85 to 95% | Main constituent of the ribbon; the SDS gives a weight range. |
| Silicon Si | 5 to 10% | Alloying element; the SDS gives a weight range. |
| Boron B | 1 to 5% | Alloying element; the SDS gives a weight range. |
| Cobalt and nickel | trace, not quantified | Trace impurities listed in the SDS; no amount is given. |
Weight shares are as printed in the sources.
What it can do
Saturation induction
1.56 T
measured
The datasheet gives a saturation induction of 1.56 T for the ribbon.
Permeability
45,000 to 600,000
measured
The product page gives a maximum DC permeability of 600,000 when annealed and 45,000 as cast. The page prints no unit.
Shielding
57,000 after relaxation
measured
In the 2015 test of a cylindrical shield in an ambient field of about 5x10-5 T, the effective relative permeability reached 57,000 after relaxation. Relaxation took a time constant of 2.6 hours.
Temperature
150 degC
measured
The product page gives a continuous service temperature of 150 degC.
How it compares
The manufacturer compares 2605SA1 with grade M3 electrical steel and says its core loss is 35% of M3 for finished cores. That comparison is the manufacturer's claim and was not measured independently in the sources read. The sources read do not compare 2605SA1 with other magnetic alloys. The table shows its values beside the figures in the datasheet.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Compare every grade in the family.
| Measurement | Fe-Si-B |
|---|---|
| Thermal behavior and safety | |
| Melting range | 1133 to 1178 °C5 |
| Physical and electrical | |
| Density, as printed in the datasheet | 7.18 g/cm³1 |
| Specific gravity from the SDS (water = 1.0) | 7.19 g/cm³2 |
| Electrical resistivity | 1.3 µΩm9 |
| Vickers hardness | 900 HV13 |
| Ribbon thickness, as printed in the datasheet | 25 µm19 |
| Temperature behavior | |
| Curie temperature, datasheet | 395 °C3 |
| Curie temperature, SDS | 392 °C4 |
| Crystallization temperature, datasheet | 510 °C6 |
| Crystallization temperature, SDS | 507 °C7 |
| Other measurements | |
| Saturation induction, as printed in the datasheet | 1.56 T8 |
| Saturation magnetostriction | 27 x10-610 |
| Young's modulus, as printed in the datasheet | 110 GPa11 |
| Tensile strength, as printed in the datasheet | 2000 N/mm212 |
| Coefficient of thermal expansion | 7.6 x10-6/°C14 |
| Lamination factorMinimum printed in a manufacturer datasheet | > 84 % |
| Core loss at 60 Hz and 1.3 T, specification limit | < 0.17 W/kg15 |
| Maximum DC permeability, annealed and as cast | 45000 to 6×10^5 -16 |
| Effective relative permeability after relaxation, cylindrical shield | 57000 -17 |
| Quasi time constant for magnetic domain relaxation | 2.6 h18 |
| Continuous service temperatureValue printed on the manufacturer product page | 150 °C |
Why choose it, and why not
Good for
- Transformer and current-transformer cores, where low core loss is the target: 0.17 W/kg or less at 60 Hz and 1.3 T (datasheet limit).
- Magnetic shielding of a steady field in a cylindrical shield, as the 2015 Fermilab test shows: effective relative permeability of 57,000 after relaxation.
Watch out for
- Permeability relaxes slowly after a change in field: the time constant is 2.6 hours, and the 2015 paper says about four days are needed to reach maximum permeability.
- The as-supplied ribbon appears to have extremely high yield strength, so forming can be difficult.
- No corrosion rate was found. The SDS only says moisture and corrosive materials can attack the product.
METGLAS 2605SA1 is a transformer-core alloy with a well-documented datasheet. Its magnetic shield use is supported by one 2015 ground test, not by a manufacturer shielding table, and its long-term corrosion and space behaviour are not documented in the sources read.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| Trade name | 2605 SA1 Iron Base Alloy, 2605SA1 |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density, as printed in the datasheet | Typical value printed in a manufacturer datasheet | grade METGLAS 2605SA1 ribboncondition as printed; table notes values are not guaranteed | — |
| 2 | Specific gravity from the SDS (water = 1.0) | Value printed in the manufacturer's material safety data sheet | grade METGLAS 2605 SA1 Iron Based Alloybasis SDS prints specific gravity with water = 1.0; numerically the same as density in g/cm3 | — |
| 3 | Curie temperature, datasheet | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribboncondition as printed; table notes values are not guaranteed | — |
| 4 | Curie temperature, SDS | Value printed in the manufacturer's material safety data sheet | grade METGLAS 2605 SA1 Iron Based Alloyprinted as 738 F (392 C) | Two manufacturer documents give different Curie temperatures (395 degC in the datasheet, 392 degC in the SDS); both are kept. |
| 5 | Melting range | Range printed in the manufacturer's material safety data sheet | grade METGLAS 2605 SA1 Iron Based Alloyprinted as 1,133-1,178 °C | — |
| 6 | Crystallization temperature, datasheet | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribboncondition as printed; table notes values are not guaranteed | — |
| 7 | Crystallization temperature, SDS | Value printed in the manufacturer's material safety data sheet | grade METGLAS 2605 SA1 Iron Based Alloyprinted as 945 F (507 C) | The datasheet gives 510 degC and the SDS 507 degC; both are kept. |
| 8 | Saturation induction, as printed in the datasheet | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribboncondition general properties table; the product page labels the value as-cast | — |
| 9 | Electrical resistivity | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribbontemperature not statedprinted as 1.3 (µΩm) | The product page prints 130 µΩ-cm for the same alloy, which is the same value in other units. |
| 10 | Saturation magnetostriction | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribbonprinted as 27 (x10-6) | — |
| 11 | Young's modulus, as printed in the datasheet | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribboncondition as printed; the product page gives a range of 100 to 110 GPa | — |
| 12 | Tensile strength, as printed in the datasheet | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribbonprinted as 2,000 (N/mm2)condition heat-treatment state not given in the table | The product page gives 1 to 2 GPa for the same property, a wider range than the single datasheet value. |
| 13 | Vickers hardness | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribbonload 50 g (Hv-50 g load) | — |
| 14 | Coefficient of thermal expansion | Typical value printed in a manufacturer datasheet | grade 2605SA1 ribbontemperature range 30 to 300 °C | — |
| 15 | Core loss at 60 Hz and 1.3 T, specification limit | Specification limit printed in a manufacturer datasheet, measured to ASTM A 932/A 932M | grade 2605SA1 transformer core ribbonfrequency 60 Hzflux density 1.3 Tstandard ASTM A 932 | The product page says the core loss is 35% of grade M3 electrical steel, for finished cores (manufacturer claim, not independently measured in the sources read). |
| 16 | Maximum DC permeability, annealed and as cast | Values printed on the manufacturer product page; the page prints no unit, and a 2015 paper calls the same quantity relative permeability | grade 2605SA1 ribbonheat treatment annealed gives the upper value, as cast the lower value | — |
| 17 | Effective relative permeability after relaxation, cylindrical shield | Measured by the authors of a 2015 paper on shielding of an ambient field | sample cylindrical shield of 23 micrometre 2605SA1 ribbonfield ambient field of about 5x10-5 T (500 mG)state after relaxation | — |
| 18 | Quasi time constant for magnetic domain relaxation | Measured by the authors of a 2015 paper on shielding of an ambient field | sample cylindrical shield of 2605SA1 ribbonfield ambient field of about 5x10-5 T (500 mG) | — |
| 19 | Ribbon thickness, as printed in the datasheet | Nominal value and tolerance printed in a manufacturer datasheet | grade 2605SA1 ribbonprinted as 25 ± 4 | Uncertainty: ±4 µmThe product page and the 2015 paper both give 23 µm for the thickness they used, so the nominal value differs by source. |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Moisture and corrosive materials (storage and incompatibilities) | not rated | The SDS says the ribbon can be attacked by moisture and corrosive materials.1 |
| Heating close to the crystallization temperature (thermal ageing) | not rated | The datasheet's reference anneal of 370 degC for 2 hours sits below the 510 degC crystallization temperature it prints.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Moisture and corrosive materials (storage and incompatibilities) | Section 10 lists moisture and corrosive materials as incompatible, and Section 7 asks that the product not be exposed to moisture or any other substance. The sheet gives no corrosion rate, test or exposure time. | — |
| 2 | Heating close to the crystallization temperature (thermal ageing) | The datasheet gives a crystallization temperature of 510 degC, and the SDS gives 507 degC (945 F). The datasheet's reference field anneal is 370 degC for 2 hours. No property change after long heating at intermediate temperatures was found in the sources read. | — |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The supplier's safety data sheet classes the ribbon as non-hazardous as shipped. The sharp edges are the main hazard.
- Edges
- The edges are very sharp. The SDS asks for cut-resistant gloves and safety glasses when the ribbon is ground, sanded, cut or welded.
- Dust and fumes
- Vapors and fumes from grinding, sanding, cutting or welding are harmful if inhaled. The SDS asks for mechanical ventilation during those operations.
- Trace metals
- Trace cobalt and nickel are listed as IARC group 2B (possible carcinogen). The SDS gives no amount for them.
If the ribbon is heated or burns
These points come from the SDS and are not based on field incidents.
- Melting range
- The SDS gives a melting range of 1,133 to 1,178 degC. If the ribbon melts or burns in a fire, toxic vapors and metallic fumes may be released.
- Fire
- The SDS says the product may burn in a structural fire and recommends self-contained breathing apparatus against the fumes.
Handling and storage
- Storage
- The SDS says to store the ribbon where it is protected from physical damage and from moisture or other contamination.
- Incompatibility
- The SDS says the product can be attacked by moisture and corrosive materials.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Fire or melting of the ribbonmoderate severity | Heating to melting, or burning in a structural fireToxic vapors and metallic fumes may be released; the SDS gives a melting range of 1,133 to 1,178 degC. |
| Slow magnetic relaxation after a change in fieldmoderate severity | A change in the ambient magnetic field of a shielded cylinderThe 2015 paper measured a quasi time constant of 2.6 hours for domain relaxation, and says maximum permeability needs about four days at room temperature after each change. |
| Difficult forming of the as-supplied ribbonlow severity | Forming the ribbon before heat treatmentThe 2015 paper says the ribbon appears to have extremely high yield strength, so formability can be problematic. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Eyes and airways of people working on the ribbon | Solid particles from grinding and sanding may irritate the eyes; vapors from cutting or welding are harmful if inhaled. |
Handling and storage
- The edges are very sharp: wear cut-resistant gloves and safety glasses when grinding, sanding, cutting or welding.
- Use mechanical ventilation when cutting, grinding, sanding or welding the ribbon.
- Store the ribbon where it is protected from physical damage and from moisture or other contamination.
Mitigations
- Field anneal at 370 degC for 2 hours in a field of 2400 A/m along the ribbon axis, the datasheet's reference treatment, to relieve stress and set the magnetic anisotropy.
- Allow about four days at room temperature for maximum permeability to be reached after a change in the magnetic environment.
Supply and geography
How common the raw materials are and where they come from.
Iron
- Top producers (2025)
- Australia 37.7%, Brazil 16.2%, India 11.9%, China 11.2%
- Recycling
- USGS iron ore chapter: 'None' for recycling, which refers readers to the Iron and Steel Scrap chapter.
- Substitutes
- USGS: the only source of primary iron is iron ore; DRI, iron nuggets and scrap are used extensively in steelmaking in electric arc furnaces.
Boron
- Critical mineral lists
- US: listed
Silicon
- Critical mineral lists
- US: listed
Silicon (silicon metal and ferrosilicon)
USGS: world and domestic resources for making silicon metal and alloys are abundant, and the silicon comes from silica in natural forms such as quartzite. USGS prints that China accounted for almost 80% of global estimated production of silicon materials in 2025; the share of 80 here is that printed figure, not a calculation.
- Top producers (2025)
- China 80%, Brazil, Norway, Russia
- Critical mineral lists
- US: listed
- Recycling
- Insignificant (USGS silicon chapter, Recycling line).
- Substitutes
- Gallium arsenide and germanium are the principal substitutes for silicon in semiconductor and infrared applications (USGS silicon chapter).; Aluminum, silicon carbide, and silicomanganese can be substituted for ferrosilicon in some applications (USGS silicon chapter).
Boron (borate minerals and refined borates)
USGS reserves, Reserves column (thousand t): United States 48,000; Turkey 950,000; Russia 40,000; Chile 35,000; China 9,100 as boric oxide equivalent; Peru 4,000. 2025 production, thousand t, as printed: Turkey refined borates 1,500; Bolivia ulexite 380; Chile ulexite 300; China boric oxide equivalent 230; Peru crude borates 220; Argentina crude ore 170; Russia datolite ore 80; Germany compounds 40. Forms and bases differ and USGS gives no world total, so no producer share is calculated. For 2021 to 2024, USGS lists Turkey at 90% of United States boron imports, all forms. USGS says world resources are adequate for the foreseeable future.
- Top producers (2025)
- Turkey, Bolivia, Chile, China, Peru, Argentina, Russia, Germany
- Critical mineral lists
- US: listed
- Recycling
- Insignificant (USGS boron chapter, Recycling line).
- Substitutes
- Sodium percarbonate can replace borates in detergents, and it requires lower temperatures to undergo hydrolysis, which is an environmental consideration (USGS boron chapter).
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: metglas-2605sa1
spore_version: 0.2
family: magnet-and-superconducting-alloys
name: METGLAS 2605SA1
abbreviation: Fe-Si-B
role: transformer core and magnetic shield
category: shielding
type: spot-shields
summary: |
METGLAS 2605SA1 is an iron-based amorphous metal ribbon from Metglas, Inc., about 23 to 25 micrometres thick. The datasheet gives a density of 7.18 g/cm3, a saturation induction of 1.56 T and a Curie temperature of 395 degC. The manufacturer offers it for transformer cores, and a 2015 Fermilab paper tested it as a magnetic shield for superconducting RF cavity cryomodules.
best_for: Low-loss transformer and current-transformer cores, where core loss of 0.17 W/kg or less at 60 Hz and 1.3 T is the target (datasheet limit)
weakest_at: Formability of the as-supplied ribbon, which the 2015 paper calls difficult because its yield strength appears extremely high; its permeability also takes about four days to reach maximum after a change in field
identity:
formula: 'Iron-based amorphous metal, Fe-Si-B ribbon: Fe 85 to 95, Si 5 to 10, B 1 to 5 (weight %, SDS ranges); trace cobalt and nickel'
crystal_system: amorphous (no crystal lattice)
source: metglas-sds
where: Section 2, Composition table (weight %)
designations:
- system: Trade name
code: 2605 SA1 Iron Base Alloy
source: metglas-sds
where: Document title, footer of every page
- system: Trade name
code: 2605SA1
source: metglas-datasheet
where: Section 1, Alloys and the specification table, column 2605SA1
tags:
environments: []
stresses: []
applications:
- electronics-and-chips
properties:
- benchmark: density
label: Density, as printed in the datasheet
value: 7.18
unit: g/cm3
scope: material
conditions:
grade: METGLAS 2605SA1 ribbon
condition: as printed; table notes values are not guaranteed
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Physical table, Density (g/cm3), row 2605SA1
- benchmark: density
label: Specific gravity from the SDS (water = 1.0)
value: 7.19
unit: g/cm3
scope: material
conditions:
grade: METGLAS 2605 SA1 Iron Based Alloy
basis: SDS prints specific gravity with water = 1.0; numerically the same as density in g/cm3
method: Value printed in the manufacturer's material safety data sheet
status: ground
source: metglas-sds
where: Section 9, Physical and chemical properties, specific gravity
- benchmark: curie_temperature
label: Curie temperature, datasheet
value: 395
unit: degC
scope: material
conditions:
grade: 2605SA1 ribbon
condition: as printed; table notes values are not guaranteed
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Electromagnetic table, Curie Temperature (degC), row 2605SA1
- benchmark: curie_temperature
label: Curie temperature, SDS
value: 392
unit: degC
scope: material
conditions:
grade: METGLAS 2605 SA1 Iron Based Alloy
printed_as: 738 F (392 C)
method: Value printed in the manufacturer's material safety data sheet
status: ground
note: Two manufacturer documents give different Curie temperatures (395 degC in the datasheet, 392 degC in the SDS); both are kept.
source: metglas-sds
where: Section 9, Curie Temperature
- benchmark: melting_point
label: Melting range
value: 1133
value_high: 1178
bound: range
unit: degC
scope: material
conditions:
grade: METGLAS 2605 SA1 Iron Based Alloy
printed_as: 1,133-1,178 degC
method: Range printed in the manufacturer's material safety data sheet
status: ground
source: metglas-sds
where: Section 5, Special fire fighting precautions and instructions
- benchmark: crystallization_temperature
label: Crystallization temperature, datasheet
value: 510
unit: degC
scope: material
conditions:
grade: 2605SA1 ribbon
condition: as printed; table notes values are not guaranteed
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Physical table, Crystallization Temperature (degC), row 2605SA1
- benchmark: crystallization_temperature
label: Crystallization temperature, SDS
value: 507
unit: degC
scope: material
conditions:
grade: METGLAS 2605 SA1 Iron Based Alloy
printed_as: 945 F (507 C)
method: Value printed in the manufacturer's material safety data sheet
status: ground
note: The datasheet gives 510 degC and the SDS 507 degC; both are kept.
source: metglas-sds
where: Section 9, Crystallization temp
- benchmark: saturation_induction
label: Saturation induction, as printed in the datasheet
value: 1.56
unit: T
scope: material
conditions:
grade: 2605SA1 ribbon
condition: general properties table; the product page labels the value as-cast
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Electromagnetic table, Saturation Induction (T), row 2605SA1
- benchmark: electrical_resistivity
label: Electrical resistivity
value: 1.3
unit: µΩm
scope: material
conditions:
grade: 2605SA1 ribbon
temperature: not stated
printed_as: 1.3 (µΩm)
method: Typical value printed in a manufacturer datasheet
status: ground
note: The product page prints 130 µΩ-cm for the same alloy, which is the same value in other units.
source: metglas-datasheet
where: Section 2, Electromagnetic table, Electrical Resistivity (µΩm), row 2605SA1
- benchmark: magnetostriction
label: Saturation magnetostriction
value: 27
unit: x10-6
scope: material
conditions:
grade: 2605SA1 ribbon
printed_as: 27 (x10-6)
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Electromagnetic table, Magnetostriction (x10-6), row 2605SA1
- benchmark: elastic_modulus
label: Young's modulus, as printed in the datasheet
value: 110
unit: GPa
scope: material
conditions:
grade: 2605SA1 ribbon
condition: as printed; the product page gives a range of 100 to 110 GPa
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Physical table, Young's Modulus (GPa), row 2605SA1
- benchmark: ultimate_tensile_strength
label: Tensile strength, as printed in the datasheet
value: 2000
unit: N/mm2
scope: material
conditions:
grade: 2605SA1 ribbon
printed_as: 2,000 (N/mm2)
condition: heat-treatment state not given in the table
method: Typical value printed in a manufacturer datasheet
status: ground
note: The product page gives 1 to 2 GPa for the same property, a wider range than the single datasheet value.
source: metglas-datasheet
where: Section 2, Physical table, Tensile Strength (N/mm2), row 2605SA1
- benchmark: vickers_hardness
label: Vickers hardness
value: 900
unit: HV
scope: material
conditions:
grade: 2605SA1 ribbon
load: 50 g (Hv-50 g load)
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Physical table, Vickers Hardness Hv-50 g load, row 2605SA1
- benchmark: cte
label: Coefficient of thermal expansion
value: 7.6
unit: x10-6/degC
scope: material
conditions:
grade: 2605SA1 ribbon
temperature_range: 30 to 300 degC
method: Typical value printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 2, Physical table, Thermal Expansion Coefficient (x10-6 /degC), 30 - 300 degC, row 2605SA1
- benchmark: lamination_factor
label: Lamination factor
value: 84
bound: lower
unit: '%'
scope: material
conditions:
grade: 2605SA1 ribbon
printed_as: greater than or equal to 84
method: Minimum printed in a manufacturer datasheet
status: ground
source: metglas-datasheet
where: Section 3, Ribbon Dimensions and Lamination Factor, row 2605SA1
- benchmark: core_loss
label: Core loss at 60 Hz and 1.3 T, specification limit
value: 0.17
bound: upper
unit: W/kg
scope: material
conditions:
grade: 2605SA1 transformer core ribbon
frequency: 60 Hz
flux_density: 1.3 T
standard: ASTM A 932
method: Specification limit printed in a manufacturer datasheet, measured to ASTM A 932/A 932M
status: ground
note: The product page says the core loss is 35% of grade M3 electrical steel, for finished cores (manufacturer claim, not independently measured in the sources read).
source: metglas-datasheet
where: Section 1, Alloys and the specification table, Core Loss (W/kg) at 60 Hz and 1.3 T
- benchmark: dc_permeability
label: Maximum DC permeability, annealed and as cast
value: 45000
value_high: 600000
bound: range
unit: '-'
scope: material
conditions:
grade: 2605SA1 ribbon
heat_treatment: annealed gives the upper value, as cast the lower value
method: Values printed on the manufacturer product page; the page prints no unit, and a 2015 paper calls the same quantity relative permeability
status: ground
source: metglas-web
where: 2605SA1 product section, Electromagnetic list, Maximum DC Permeability (annealed; as cast)
- benchmark: effective_relative_permeability
label: Effective relative permeability after relaxation, cylindrical shield
value: 57000
unit: '-'
scope: material
conditions:
sample: cylindrical shield of 23 micrometre 2605SA1 ribbon
field: ambient field of about 5x10-5 T (500 mG)
state: after relaxation
method: Measured by the authors of a 2015 paper on shielding of an ambient field
status: ground
source: crawford2015
where: Abstract
- benchmark: magnetic_relaxation_time
label: Quasi time constant for magnetic domain relaxation
value: 2.6
unit: h
scope: material
conditions:
sample: cylindrical shield of 2605SA1 ribbon
field: ambient field of about 5x10-5 T (500 mG)
method: Measured by the authors of a 2015 paper on shielding of an ambient field
status: ground
source: crawford2015
where: Abstract
- benchmark: max_service_temp
label: Continuous service temperature
value: 150
unit: degC
scope: material
conditions:
grade: 2605SA1 ribbon
basis: Continuous Service Temp. in the Physical list on the product page
method: Value printed on the manufacturer product page
status: ground
source: metglas-web
where: 2605SA1 product section, Physical list, Continuous Service Temp. (degC)
- benchmark: thickness
label: Ribbon thickness, as printed in the datasheet
value: 25
uncertainty: ±4 µm
unit: µm
scope: material
conditions:
grade: 2605SA1 ribbon
printed_as: 25 ± 4
method: Nominal value and tolerance printed in a manufacturer datasheet
status: ground
note: The product page and the 2015 paper both give 23 µm for the thickness they used, so the nominal value differs by source.
source: metglas-datasheet
where: Section 3, Ribbon Dimensions and Lamination Factor, Thickness (µm), row 2605SA1
corrosion:
- environment: Moisture and corrosive materials (storage and incompatibilities)
headline: The SDS says the ribbon can be attacked by moisture and corrosive materials.
effect: Section 10 lists moisture and corrosive materials as incompatible, and Section 7 asks that the product not be exposed to moisture or any other substance. The sheet gives no corrosion rate, test or exposure time.
rating: unknown
source: metglas-sds
where: Section 10, Incompatibilities; Section 7, Storage recommendations
- environment: Heating close to the crystallization temperature (thermal ageing)
headline: The datasheet's reference anneal of 370 degC for 2 hours sits below the 510 degC crystallization temperature it prints.
effect: The datasheet gives a crystallization temperature of 510 degC, and the SDS gives 507 degC (945 F). The datasheet's reference field anneal is 370 degC for 2 hours. No property change after long heating at intermediate temperatures was found in the sources read.
rating: unknown
source: metglas-datasheet
where: Section 2, Physical table, Crystallization Temperature; Section 4, introductory text (heat treatment)
risks:
hazards:
- text: The SDS says the ribbon is non-hazardous as shipped; the main hazard as shipped is the sharp edges of the product.
ghs: []
source: metglas-sds
where: Section 3, Emergency overview and Potential health hazards
- text: Vapors and fumes from grinding, sanding, cutting or welding are harmful if inhaled and may irritate the throat and respiratory tract.
ghs: []
source: metglas-sds
where: Section 3, Inhalation
- text: Trace cobalt and nickel are listed as IARC group 2B (possible carcinogen); the SDS does not give an amount for them.
ghs: []
source: metglas-sds
where: Section 3, Delayed effects and carcinogen table; Section 2
- text: 'Cobalt, one of the trace elements the SDS lists in the ribbon, has these GHS hazard statements in PubChem for the element: H317 (may cause an allergic skin reaction), H334 (may cause allergy or asthma symptoms or breathing difficulties if inhaled), H341 (suspected of causing genetic defects), H350 (may cause cancer), H360F (may damage fertility) and H413 (may cause long lasting harmful effects to aquatic life). The SDS gives no amount of cobalt for this ribbon.'
ghs:
- H317
- H334
- H341
- H350
- H360F
- H413
source: pubchem-cobalt
where: GHS Classification section, GHS Hazard Statements list (cobalt, CID 104730)
failure_risks:
- mode: Fire or melting of the ribbon
trigger: Heating to melting, or burning in a structural fire
consequence: Toxic vapors and metallic fumes may be released; the SDS gives a melting range of 1,133 to 1,178 degC.
severity: moderate
source: metglas-sds
where: Section 3 and Section 5
- mode: Slow magnetic relaxation after a change in field
trigger: A change in the ambient magnetic field of a shielded cylinder
consequence: The 2015 paper measured a quasi time constant of 2.6 hours for domain relaxation, and says maximum permeability needs about four days at room temperature after each change.
severity: moderate
source: crawford2015
where: Abstract; Conclusion
- mode: Difficult forming of the as-supplied ribbon
trigger: Forming the ribbon before heat treatment
consequence: The 2015 paper says the ribbon appears to have extremely high yield strength, so formability can be problematic.
severity: low
source: crawford2015
where: Metglas 2605SA1 Properties section
side_effects:
- text: Solid particles from grinding and sanding may irritate the eyes; vapors from cutting or welding are harmful if inhaled.
affects: Eyes and airways of people working on the ribbon
source: metglas-sds
where: Section 3, Eyes and Inhalation
handling:
- text: 'The edges are very sharp: wear cut-resistant gloves and safety glasses when grinding, sanding, cutting or welding.'
source: metglas-sds
where: Section 7, Normal handling; Section 8, Personal protective equipment
- text: Use mechanical ventilation when cutting, grinding, sanding or welding the ribbon.
source: metglas-sds
where: Section 8, Engineering controls
- text: Store the ribbon where it is protected from physical damage and from moisture or other contamination.
source: metglas-sds
where: Section 7, Storage recommendations
mitigations:
- text: Field anneal at 370 degC for 2 hours in a field of 2400 A/m along the ribbon axis, the datasheet's reference treatment, to relieve stress and set the magnetic anisotropy.
source: metglas-datasheet
where: Section 4, introductory text
- text: Allow about four days at room temperature for maximum permeability to be reached after a change in the magnetic environment.
source: crawford2015
where: Conclusion
uses:
- application: electronics-and-chips
device: Distribution, commercial and industrial transformer cores
example: The datasheet lists 2605SA1 for single and three phase commercial, industrial and distribution transformers, with core loss of 0.17 W/kg or less at 60 Hz and 1.3 T.
source: metglas-datasheet
where: Introduction paragraph; Section 1 table
- application: electronics-and-chips
device: Magnetic shield for superconducting RF cavity cryomodules
example: A 2015 Fermilab paper says 2605SA1 is useful as a magnetic shield for certain applications in superconducting RF cavity cryomodules, and measured its attenuation of a steady field of about 5x10-5 T.
source: crawford2015
where: Introduction
- application: electronics-and-chips
device: Current transformers, high-frequency inductors and motors
example: The manufacturer's product page lists current transformers, high-frequency inductors and motors among the applications for 2605SA1.
source: metglas-web
where: 2605SA1 product section, Applications
supply:
- subject: Iron
producers:
- country: Australia
share_percent: 37.7
year: 2025
- country: Brazil
share_percent: 16.2
year: 2025
- country: India
share_percent: 11.9
year: 2025
- country: China
share_percent: 11.2
year: 2025
critical_lists: []
recycling: 'USGS iron ore chapter: ''None'' for recycling, which refers readers to the Iron and Steel Scrap chapter.'
substitutes:
- 'USGS: the only source of primary iron is iron ore; DRI, iron nuggets and scrap are used extensively in steelmaking in electric arc furnaces.'
source: usgs-mcs2026-iron
where: World Mine Production and Reserves table, usable ore, 2025e (world total 2,600,000 thousand t; shares calculated by Space Mushroom against that total); Recycling; Substitutes
- subject: Boron
producers: []
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
substitutes: []
source: usgs-mcs2026-iron
where: 'Critical Minerals paragraph: boron was added to the 2025 list (USGS iron ore chapter, citing 90 FR 50494)'
- subject: Silicon
producers: []
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
substitutes: []
source: usgs-mcs2026-iron
where: 'Critical Minerals paragraph: silicon was added to the 2025 list (USGS iron ore chapter)'
- subject: Silicon (silicon metal and ferrosilicon)
abundance: 'USGS: world and domestic resources for making silicon metal and alloys are abundant, and the silicon comes from silica in natural forms such as quartzite. USGS prints that China accounted for almost 80% of global estimated production of silicon materials in 2025; the share of 80 here is that printed figure, not a calculation.'
producers:
- country: China
share_percent: 80
year: 2025
- country: Brazil
year: 2025
- country: Norway
year: 2025
- country: Russia
year: 2025
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
recycling: Insignificant (USGS silicon chapter, Recycling line).
substitutes:
- Gallium arsenide and germanium are the principal substitutes for silicon in semiconductor and infrared applications (USGS silicon chapter).
- Aluminum, silicon carbide, and silicomanganese can be substituted for ferrosilicon in some applications (USGS silicon chapter).
source: usgs-mcs2026-silicon
where: World Production table, 2025 column (thousand t, silicon content; Brazil, Norway and Russia as listed, China shares as printed in Events, Trends, and Issues); Recycling; Substitutes; Critical list paragraph
- subject: Boron (borate minerals and refined borates)
abundance: 'USGS reserves, Reserves column (thousand t): United States 48,000; Turkey 950,000; Russia 40,000; Chile 35,000; China 9,100 as boric oxide equivalent; Peru 4,000. 2025 production, thousand t, as printed: Turkey refined borates 1,500; Bolivia ulexite 380; Chile ulexite 300; China boric oxide equivalent 230; Peru crude borates 220; Argentina crude ore 170; Russia datolite ore 80; Germany compounds 40. Forms and bases differ and USGS gives no world total, so no producer share is calculated. For 2021 to 2024, USGS lists Turkey at 90% of United States boron imports, all forms. USGS says world resources are adequate for the foreseeable future.'
producers:
- country: Turkey
year: 2025
- country: Bolivia
year: 2025
- country: Chile
year: 2025
- country: China
year: 2025
- country: Peru
year: 2025
- country: Argentina
year: 2025
- country: Russia
year: 2025
- country: Germany
year: 2025
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
recycling: Insignificant (USGS boron chapter, Recycling line).
substitutes:
- Sodium percarbonate can replace borates in detergents, and it requires lower temperatures to undergo hydrolysis, which is an environmental consideration (USGS boron chapter).
source: usgs-mcs2026-boron
where: Salient Statistics (Recycling; Import Sources 2021 to 2024); World Production and Reserves table (2024 and 2025 production, Reserves column); Critical list paragraph; Substitutes
documents:
- title: 'METGLAS Amorphous Alloys for Transformer Cores: 2605SA1 and 2605HB1M technical data (25 pages, dated 29 April 2011)'
type: datasheet
url: https://metglas.com/wp-content/uploads/2021/06/2605SA1-Magnetic-Alloy-Updated.pdf
year: 2011
- title: 'METGLAS 2605 SA1 Iron Based Alloy: Material Safety Data Sheet (FRM 8200.005 Rev. 02)'
type: sds
url: https://metglas.com/wp-content/uploads/2016/12/METGLAS-2605-SA1-Iron-Based-Alloy.pdf
year: 2013
- title: Observation of Magnetic Superviscosity in Metglas 2605SA1 (arXiv:1511.05127)
type: paper
url: https://arxiv.org/pdf/1511.05127
year: 2015
- title: Mineral Commodity Summaries 2026, Iron Ore (USGS)
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-ore.pdf
year: 2026
- title: Mineral Commodity Summaries 2026, Silicon (USGS)
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf
year: 2026
- title: Mineral Commodity Summaries 2026, Boron (USGS)
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf
year: 2026
- title: PubChem compound record for cobalt (CID 104730), GHS Classification
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
gaps:
- No corrosion rate, humidity test, salt-spray result or exposure time for 2605SA1 was found in the sources read; the only corrosion statement is the SDS line that moisture and corrosive materials can attack the product.
- No UNS, EN, ASTM, JIS or AISI designation for 2605SA1 was printed in the sources read. Only the trade names METGLAS 2605 SA1 and 2605SA1 are listed.
- No atomic-percent composition was read. The composition is the SDS weight-percent ranges, which the 2015 paper also quotes; the SDS does not say whether the ranges are weight or atomic percent, but the table is headed weight %.
- The datasheet is dated 29 April 2011, and its table values are marked not guaranteed. No newer datasheet was found in this run.
- The product page does not list 2605SA1 among the shielding alloys (it lists 2705M, 2714A and 2826MB for shielding). The magnetic shield use rests on the 2015 Fermilab paper alone.
- No vacuum, cryogenic, radiation or flight data for 2605SA1 were found in the sources read; the 2015 shield measurement was a ground test in a single cylindrical geometry.
- Maximum DC permeability on the product page carries no unit; it is entered as a dimensionless value, as the 2015 paper describes it.
- 'Supply: the USGS iron ore chapter gives production shares for iron only. The USGS boron chapter gives producer quantities but no world total, so no boron producer share is calculated. For silicon, USGS prints only that China accounted for almost 80% of global production. No crustal abundance for boron or silicon was read.'
- Hardness, saturation induction, core loss, lamination factor, magnetostriction, crystallization temperature and magnetic relaxation time use names outside the canonical list (property-canon.yaml), as no canonical name fits.
sources:
metglas-datasheet:
title: 'METGLAS Amorphous Alloys for Transformer Cores: 2605SA1 and 2605HB1M technical data'
id: Metglas, Inc. technical data, 25 pages, dated 29 April 2011 (PDF modified 2021)
url: https://metglas.com/wp-content/uploads/2021/06/2605SA1-Magnetic-Alloy-Updated.pdf
year: 2011
kind: datasheet
license: manufacturer document, linked not reproduced
metglas-web:
title: 'METGLAS Magnetic Materials: 2605SA1 product section (General Properties and Characteristics)'
id: Metglas, Inc. product page, undated; news item on the page is dated April 2026
url: https://metglas.com/magnetic-materials/
year: 2026
kind: web
license: manufacturer web page, linked not reproduced
metglas-sds:
title: 'Material Safety Data Sheet: METGLAS 2605 SA1 Iron Based Alloy'
id: FRM 8200.005 Rev. 02; initial release October 2003, revision 02 dated 04/16/13
url: https://metglas.com/wp-content/uploads/2016/12/METGLAS-2605-SA1-Iron-Based-Alloy.pdf
year: 2013
kind: datasheet
license: supplier document, linked not reproduced
crawford2015:
title: Observation of Magnetic Superviscosity in Metglas 2605SA1
id: arXiv:1511.05127 (A. C. Crawford, Fermilab, 16 November 2015)
url: https://arxiv.org/pdf/1511.05127
year: 2015
kind: paper
license: arXiv preprint
usgs-mcs2026-iron:
title: Mineral Commodity Summaries 2026, Iron Ore
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-iron-ore.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-silicon:
title: Mineral Commodity Summaries 2026, Silicon
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silicon.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-boron:
title: Mineral Commodity Summaries 2026, Boron
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf
year: 2026
kind: report
license: public domain (USGS)
pubchem-cobalt:
title: PubChem compound summary for cobalt (CID 104730), GHS Classification
id: PubChem CID 104730 (Cobalt), NCBI PubChem
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
kind: database
license: NCBI PubChem, free public database
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 21
unreachable: 0
caveats: 2
note: Read by an AI assistant on 2026-11-01 from the cited datasheet, product page, SDS, 2015 paper and USGS chapter; values copied as printed. Shares of iron production are calculated from the USGS table.
story:
recipe:
line: METGLAS 2605SA1 is a ribbon of iron with silicon and boron. The SDS gives weight ranges rather than a fixed formula. The ribbon is amorphous, so it has no crystal structure and no grain boundaries, as the 2015 paper notes.
parts:
- name: Iron
symbol: Fe
share_percent: 85
share_high: 95
role: Main constituent of the ribbon; the SDS gives a weight range.
source: metglas-sds
where: Section 2, Composition table, weight %
- name: Silicon
symbol: Si
share_percent: 5
share_high: 10
role: Alloying element; the SDS gives a weight range.
source: metglas-sds
where: Section 2, Composition table, weight %
- name: Boron
symbol: B
share_percent: 1
share_high: 5
role: Alloying element; the SDS gives a weight range.
source: metglas-sds
where: Section 2, Composition table, weight %
- name: Cobalt and nickel
role: Trace impurities listed in the SDS; no amount is given.
share_note: trace, not quantified
source: metglas-sds
where: Section 2 and Section 3, carcinogen table
risk_groups:
- title: For people
level: 1
verdict: Non-hazardous as shipped
lead: The supplier's safety data sheet classes the ribbon as non-hazardous as shipped. The sharp edges are the main hazard.
points:
- label: Edges
line: The edges are very sharp. The SDS asks for cut-resistant gloves and safety glasses when the ribbon is ground, sanded, cut or welded.
- label: Dust and fumes
line: Vapors and fumes from grinding, sanding, cutting or welding are harmful if inhaled. The SDS asks for mechanical ventilation during those operations.
- label: Trace metals
line: Trace cobalt and nickel are listed as IARC group 2B (possible carcinogen). The SDS gives no amount for them.
- title: If the ribbon is heated or burns
level: 2
verdict: Toxic fumes if melted
lead: These points come from the SDS and are not based on field incidents.
points:
- label: Melting range
line: The SDS gives a melting range of 1,133 to 1,178 degC. If the ribbon melts or burns in a fire, toxic vapors and metallic fumes may be released.
- label: Fire
line: The SDS says the product may burn in a structural fire and recommends self-contained breathing apparatus against the fumes.
- title: Handling and storage
points:
- label: Storage
line: The SDS says to store the ribbon where it is protected from physical damage and from moisture or other contamination.
- label: Incompatibility
line: The SDS says the product can be attacked by moisture and corrosive materials.
why: METGLAS 2605SA1 is an iron-based amorphous metal ribbon made by Metglas, Inc. Its atoms do not sit in a crystal lattice, so the ribbon has no grain boundaries, as a 2015 Fermilab paper explains. The manufacturer offers it for transformer cores, current transformers and high-frequency inductors. The same 2015 paper tested it as a magnetic shield for superconducting RF cavity cryomodules, which is the space-adjacent use in this profile.
uses:
- where: Transformer cores
line: The manufacturer's datasheet lists 2605SA1 for single and three phase commercial, industrial and distribution transformers. The core loss limit is 0.17 W/kg at 60 Hz and 1.3 T.
- where: Magnetic shield for superconducting RF cryomodules
line: A 2015 Fermilab paper says 2605SA1 is useful as a magnetic shield for certain superconducting RF cavity cryomodules. The authors measured its shielding of a steady field of about 5x10-5 T.
can_do:
- label: Saturation induction
benchmark: saturation_induction
line: The datasheet gives a saturation induction of 1.56 T for the ribbon.
- label: Permeability
benchmark: dc_permeability
value: 45,000 to 600,000
line: The product page gives a maximum DC permeability of 600,000 when annealed and 45,000 as cast. The page prints no unit.
- label: Shielding
benchmark: effective_relative_permeability
value: 57,000 after relaxation
line: In the 2015 test of a cylindrical shield in an ambient field of about 5x10-5 T, the effective relative permeability reached 57,000 after relaxation. Relaxation took a time constant of 2.6 hours.
- label: Temperature
benchmark: max_service_temp
value: 150 degC
line: The product page gives a continuous service temperature of 150 degC.
compare: The manufacturer compares 2605SA1 with grade M3 electrical steel and says its core loss is 35% of M3 for finished cores. That comparison is the manufacturer's claim and was not measured independently in the sources read. The sources read do not compare 2605SA1 with other magnetic alloys. The table shows its values beside the figures in the datasheet.
compare_rows:
- label: Density
benchmark: density
- label: Saturation induction
benchmark: saturation_induction
- label: Curie temperature
benchmark: curie_temperature
handling:
- The ribbon is non-hazardous as shipped, but its edges are very sharp. Wear cut-resistant gloves.
- Ventilate when cutting, grinding, sanding or welding, and wear safety glasses.
- Store it away from moisture and corrosive materials.
- Anneal it in a field along the ribbon axis, at 370 degC for 2 hours, as the datasheet's reference treatment.
good_for:
- 'Transformer and current-transformer cores, where low core loss is the target: 0.17 W/kg or less at 60 Hz and 1.3 T (datasheet limit).'
- 'Magnetic shielding of a steady field in a cylindrical shield, as the 2015 Fermilab test shows: effective relative permeability of 57,000 after relaxation.'
watch_out:
- 'Permeability relaxes slowly after a change in field: the time constant is 2.6 hours, and the 2015 paper says about four days are needed to reach maximum permeability.'
- The as-supplied ribbon appears to have extremely high yield strength, so forming can be difficult.
- No corrosion rate was found. The SDS only says moisture and corrosive materials can attack the product.
verdict: METGLAS 2605SA1 is a transformer-core alloy with a well-documented datasheet. Its magnetic shield use is supported by one 2015 ground test, not by a manufacturer shielding table, and its long-term corrosion and space behaviour are not documented in the sources read.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| METGLAS Amorphous Alloys for Transformer Cores: 2605SA1 and 2605HB1M technical data | datasheet | 2011 | 16 values | |
| METGLAS Magnetic Materials: 2605SA1 product section (General Properties and Characteristics) | web | 2026 | 3 values | |
| Material Safety Data Sheet: METGLAS 2605 SA1 Iron Based Alloy | datasheet | 2013 | 14 values | |
| Observation of Magnetic Superviscosity in Metglas 2605SA1 | paper | 2015 | 6 values | |
| Mineral Commodity Summaries 2026, Iron Ore | report | 2026 | 3 values | |
| Mineral Commodity Summaries 2026, Silicon | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026, Boron | report | 2026 | 1 value | |
| PubChem compound summary for cobalt (CID 104730), GHS Classification | database | 1 value |
Updated