METGLAS 2605S3A
Iron-based amorphous metal ribbon. The SDS gives composition as percentage ranges: iron 69 to 100, silicon 0 to 10, niobium 0 to 7, boron 0 to 5, chromium 0 to 5, manganese 0 to 2, copper 0 to 2. The basis is not stated, and the SDS says ranges may reflect batch variation.
Also known as 2605S3A, METGLAS Alloy 2605S3A
METGLAS 2605S3A is an iron-based amorphous metal ribbon made by Metglas, Inc.
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
1.41 T
Permeability
35,000 annealed; above 20,000 as cast
Continuous temperature
150 °C
Lamination
> 75 %
Recipe, share of the weight
- Fe 69 to 100%Iron
- Si 0 to 10%Silicon
- Nb 0 to 7%Niobium
- B 0 to 5%Boron
- Cr 0 to 5%Chromium
- Mn 0 to 2%Manganese
- Cu 0 to 2%Copper
Best for
High-frequency cores, current transformers and ground fault protection devices, the three applications the manufacturer lists
Weakest at
Corrosion data: the SDS lists moisture and corrosive materials as incompatible and prints no corrosion rate
Risk at a glance
- People Low. Not classified under OSHA HCS
- If it fails Moderate. Melting or burning of the ribbon
- Corrosion No data. No corrosion data recorded
Quick facts: METGLAS 2605S3A
| Property | Value | Basis |
|---|---|---|
| Density | 7.29 g/cm³ | 2 sourced values across conditions |
| Tensile strength | 1,000 to 2,000 MPa | 1 sourced value |
| Young's modulus | 100 to 110 GPa | 1 sourced value |
| Thermal expansion (CTE) | 6.7 ppm/K | 1 sourced value |
| Melting point | 1,180 °C | 1 sourced value |
| Electrical resistivity | 0.0000014 Ω·m | 1 sourced value |
| Maximum service temperature | 150 °C | 1 sourced value |
What is the density of METGLAS 2605S3A?
METGLAS 2605S3A has a density of 7.29 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 2605S3A?
METGLAS 2605S3A has a coefficient of thermal expansion of 6.7 ppm/K. The source and test conditions are listed in the properties table on this page.
What is the melting point of METGLAS 2605S3A?
METGLAS 2605S3A has a melting point of 1,180 °C. The source and test conditions are listed in the properties table on this page.
What is the tensile strength of METGLAS 2605S3A?
METGLAS 2605S3A has a tensile strength of 1,000 to 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 2605S3A?
METGLAS 2605S3A has a Young's modulus of 100 to 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 2605S3A?
METGLAS 2605S3A is also written as 2605S3A, METGLAS Alloy 2605S3A. Each code is printed in the source listed beside it in the designations table.
What is METGLAS 2605S3A used for?
Uses recorded in the sources include Current transformers; Ground fault protection devices; High-frequency cores.
Why it exists
METGLAS 2605S3A is an iron-based amorphous metal ribbon made by Metglas, Inc. The safety data sheet names it as an amorphous metal ribbon for the electrical industry. The manufacturer's bulletin lists it for current transformers, ground fault protection devices and high-frequency cores. The bulletin claims a high operating temperature with minimal flux density reduction, and the ASM Alloy Digest abstract calls it an iron-base alloy with high permeability.
Where it's used
Current transformers and ground fault protection
The manufacturer's bulletin names current transformers and ground fault protection devices as applications for 2605S3A.
High-frequency cores
The bulletin lists high-frequency cores as an application and gives as a benefit "Low core loss at high frequencies (>1 kHz)".
Recipe
Iron-based amorphous metal ribbon. The SDS gives composition as percentage ranges: iron 69 to 100, silicon 0 to 10, niobium 0 to 7, boron 0 to 5, chromium 0 to 5, manganese 0 to 2, copper 0 to 2. The basis is not stated, and the SDS says ranges may reflect batch variation.
METGLAS 2605S3A is an iron-based ribbon. The safety data sheet lists its ingredients as percentage ranges rather than a fixed formula. Amorphous metals are non-crystalline with a glass-like structure, according to the Wikipedia article on metallic glass, and the SDS gives 'Amorphous Metal Ribbon' as the product's other name.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Iron Fe | 69 to 100% | Main constituent; the SDS gives a range. |
| Silicon Si | 0 to 10% | Alloying element; the SDS gives a range. |
| Niobium Nb | 0 to 7% | Alloying element; the SDS gives a range. |
| Boron B | 0 to 5% | Ingredient listed in the SDS; the SDS gives a range. |
| Chromium Cr | 0 to 5% | Ingredient listed in the SDS; the SDS gives a range. |
| Manganese Mn | 0 to 2% | Ingredient listed in the SDS; the SDS gives a range. |
| Copper Cu | 0 to 2% | Ingredient listed in the SDS; the SDS gives a range. |
Weight shares are as printed in the sources.
What it can do
Saturation induction
1.41 T
measured
The bulletin gives a saturation induction of 1.41 T for the ribbon.
Permeability
35,000 annealed; above 20,000 as cast
measured
The bulletin gives a maximum DC permeability of 35,000 when annealed and above 20,000 as cast. It prints no unit for this value, so the profile enters it as a dimensionless number.
Continuous temperature
150 °C
measured
The bulletin gives a continuous service temperature of 150 °C.
Lamination
> 75 %
measured
The bulletin gives a lamination factor above 75 %, which the profile records as a lower bound.
How it compares
The sources read do not compare METGLAS 2605S3A with other magnetic alloys. Within its own bulletin the density is 7.29 g/cm3 and the Curie temperature is 358 °C, and the product page prints the same values. The product page lists 2605S3A alongside other Metglas alloys, but this profile records only the values printed for 2605S3A itself.
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. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | METGLAS 2605S3A | NdFeB | SmCo | Alnico | FeCoV | CoFe / Co-W / Co-Ti / Co-Al | Ni-Fe-Mo | Ni-Fe-Mo | Fe-Si | MG | NbTi | MgB2, REBCO, BSCCO |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thermal behavior and safety | ||||||||||||
| Melting point | 1180 °C16 | no data | no data | 1200 to 1450 °C | no data | no data | 1450 °C | 1450 °C | no data | 969 to 1024 °C | 2300 °C | 830 °C |
| Physical and electrical | ||||||||||||
| Density, technical bulletin | 7.29 g/cm³1 | 7.6 g/cm³ | 8.2 to 8.4 g/cm³ | 6.9 to 7.3 g/cm³ | 8.12 g/cm³ | 7.9 g/cm³ | 8.7 g/cm³ | 8.7 g/cm³ | 7.6 kg/dm3 | 7.18 g/cm³ | 6.4 to 6.5 g/cm³ | 2.57 g/cm³ |
| Relative density, safety data sheet | 7 to 7.5 -2 | 7.6 g/cm³ | 8.2 to 8.4 g/cm³ | 6.9 to 7.3 g/cm³ | 8.12 g/cm³ | 7.9 g/cm³ | 8.7 g/cm³ | 8.7 g/cm³ | 7.6 kg/dm3 | 7.18 g/cm³ | 6.4 to 6.5 g/cm³ | 2.57 g/cm³ |
| Electrical resistivity | 138 µΩ-cm7 | 150 uohm cm | 80 to 90 uohm cm | 45 to 75 uohm cm | 0.401 Ω·mm²/m | 0.3 µΩm | 55 µΩcm | 60 µΩ·cm | 59 µΩ·cm | 1.3 µΩm | no data | no data |
| Ribbon thickness | 18 microns9 | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Temperature behavior | ||||||||||||
| Curie temperature | 358 °C8 | 310 °C | 700 to 750 °C | 860 °C | 950 °C | 940 °C | 410 °C | 420 °C | no data | 395 °C | no data | no data |
| Crystallization temperature | 535 °C14 | no data | no data | no data | no data | no data | no data | no data | no data | 510 °C | no data | no data |
| Other measurements | ||||||||||||
| Saturation induction | 1.41 T3 | no data | no data | no data | 2.35 T | no data | 0.8 T | 0.75 T | no data | 1.56 T | no data | no data |
| Maximum DC permeability, annealed | 35000 -4 | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Maximum DC permeability, as cast | > 20000 -5 | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Saturation magnetostriction | 20 ppm6 | no data | no data | no data | no data | no data | no data | no data | no data | 27 x10-6 | no data | no data |
| Tensile strength | 1 to 2 GPa10 | no data | no data | no data | 350 MPa | no data | 450 N/mm2 | 500 to 700 N/mm2 | 535 MPa | 2000 N/mm2 | no data | no data |
| Elastic modulus | 100 to 110 GPa11 | no data | 1.2 10^11 N/m2 | no data | 190 to 210 GPa | 440 GPa | 190 to 221 kN/mm2 | 190 to 221 kN/mm2 | 185 GPa | 110 GPa | no data | 149 to 186 GPa |
| Lamination factor | > 75 %12 | no data | no data | no data | no data | no data | no data | no data | no data | 84 % | no data | no data |
| Coefficient of thermal expansion | 6.7 ppm/°C13 | 7 1e-6 per °C (dL/L) | 8 to 10 1e-6 per °C | 11 to 13 1e-6 per °C | 9.4 ppm/K | no data | 12 10-6/K | 12 10-6/K | 12 10-6/C | 7.6 x10-6/°C | no data | no data |
| Continuous service temperature | 150 °C15 | 80 °C | 250 °C | 525 °C | no data | no data | no data | no data | no data | 90 °C | no data | no data |
Why choose it, and why not
Good for
- Current transformers and ground fault protection devices, two of the three applications in the manufacturer's bulletin.
- High-frequency cores, where the manufacturer claims a high operating temperature with minimal flux density reduction.
Watch out for
- No core-loss value is printed for this grade: the bulletin shows a core-loss curve as an image only.
- No corrosion rate is printed; the SDS lists moisture and corrosive materials as incompatible.
- The SDS covers FT-3W and 2605S3A in one document, so its composition, melting point and hazard entries may not apply to 2605S3A alone.
- Magnetic relaxation after a change in field, and forming behaviour, are not documented for this grade in the sources read.
METGLAS 2605S3A is a documented iron-based amorphous ribbon for high-frequency cores, current transformers and ground fault protection devices. Its bulletin and product page print the same values. Its core loss, corrosion behaviour and long-term magnetic stability 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 | 2605S3A, METGLAS Alloy 2605S3A |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density, technical bulletin | Value printed in the manufacturer's technical bulletin; the product page prints the same value | grade METGLAS Alloy 2605S3A ribboncondition as printed; heat-treatment state not stated | — |
| 2 | Relative density, safety data sheet | Range printed in the manufacturer's safety data sheet; a dimensionless ratio, so entered with unit - | basis printed as relative density with water = 1; no unit printeddocument combined FT-3W and 2605S3A SDS, Metglas, Inc. | — |
| 3 | Saturation induction | Value printed in the manufacturer's technical bulletin; the product page prints the same value | grade METGLAS Alloy 2605S3A ribboncondition as printed; heat-treatment state not stated | — |
| 4 | Maximum DC permeability, annealed | Value printed in the manufacturer's technical bulletin, which gives the symbol mu with no unit; entered as a dimensionless relative permeability | grade METGLAS Alloy 2605S3A ribbonheat treatment annealed | — |
| 5 | Maximum DC permeability, as cast | Minimum printed in the manufacturer's technical bulletin as greater than 20,000, with no unit; entered as a dimensionless relative permeability | grade METGLAS Alloy 2605S3A ribbonheat treatment as cast | — |
| 6 | Saturation magnetostriction | Value printed in the manufacturer's technical bulletin | grade METGLAS Alloy 2605S3A ribbon | — |
| 7 | Electrical resistivity | Value printed on the manufacturer's product page; the bulletin prints the same value | grade METGLAS Alloy 2605S3A ribbontemperature not stated | The bulletin's text layer shows the unit as µ-cm; the product page prints µΩ-cm. |
| 8 | Curie temperature | Value printed in the manufacturer's technical bulletin; the product page prints the same value | grade METGLAS Alloy 2605S3A ribbon | — |
| 9 | Ribbon thickness | Value printed on the manufacturer's product page; the technical bulletin does not give a thickness | grade METGLAS Alloy 2605S3A ribbonprinted as Thickness (microns) 18 | — |
| 10 | Tensile strength | Range printed in the manufacturer's technical bulletin; the product page prints the same range | grade METGLAS Alloy 2605S3A ribbonprinted as 1-2condition heat-treatment state not stated | — |
| 11 | Elastic modulus | Range printed in the manufacturer's technical bulletin; the product page prints the same range | grade METGLAS Alloy 2605S3A ribbonprinted as 100-110 | — |
| 12 | Lamination factor | Minimum printed in the manufacturer's technical bulletin | grade METGLAS Alloy 2605S3A ribbonprinted as >75 | — |
| 13 | Coefficient of thermal expansion | Value printed in the manufacturer's technical bulletin | grade METGLAS Alloy 2605S3A ribbontemperature range not printed in the bulletin | — |
| 14 | Crystallization temperature | Value printed in the manufacturer's technical bulletin; the bulletin does not say what happens to properties above it | grade METGLAS Alloy 2605S3A ribbon | — |
| 15 | Continuous service temperature | Value printed in the manufacturer's technical bulletin; the product page prints the same value | grade METGLAS Alloy 2605S3A ribbonbasis continuous service temperature as printed | — |
| 16 | Melting point | Value printed in the manufacturer's safety data sheet, which covers two products in one document | document combined FT-3W and 2605S3A SDSprinted as 1180°C (2156°F) | — |
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 lists moisture and corrosive materials as incompatible with the product.1 |
| Heating near the crystallization temperature (thermal ageing) | not rated | The bulletin prints a crystallization temperature of 535 °C and a continuous service temperature of 150 °C.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Moisture and corrosive materials (storage and incompatibilities) | The SDS gives no corrosion rate, test result or exposure time for the ribbon. | — |
| 2 | Heating near the crystallization temperature (thermal ageing) | The sources read give no ageing or property-change data after long heating at these temperatures. | — |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The safety data sheet says the ribbon is not considered hazardous under the OSHA Hazard Communication Standard. Its sharp or heavy edges are the practical hazard.
- Edges and weight
- The SDS asks for care with items that are sharp or heavy, and for cut-resistant gloves.
- Fumes
- The SDS notes that metal fume fever may follow exposure to high concentrations of fumes.
- Ingredients
- The SDS lists chromium with an IARC entry printed as 3, and manganese as a repeated-exposure hazard in Category 2, affecting the central nervous system and lungs.
If the ribbon melts or burns
These points come from the SDS and the bulletin, not from field incidents.
- Melting point
- The SDS gives a melting point of 1180 °C. Decomposition products may include metal oxides and toxic vapour.
- Crystallization
- The bulletin gives a crystallization temperature of 535 °C but does not say what happens to the ribbon's properties above it.
Handling and storage
- Storage
- The SDS says to store the ribbon according to local regulations, and to check Section 10 for incompatible materials, which include moisture and corrosive materials.
- Service temperature
- The bulletin gives a continuous service temperature of 150 °C.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Melting or burning of the ribbonmoderate severity | Heating to the melting point, or a structural fireThe SDS gives a melting point of 1180 °C and says decomposition products may include metal oxides and toxic vapour. |
| Heating above the crystallization temperaturemoderate severity | Exposure above 535 °CThe bulletin prints the crystallization temperature but states no property change above it. |
| Attack by moisture or corrosive materialslow severity | Storage or use with moisture or corrosive materialsThe SDS lists both as incompatible with the product; no damage rate is printed. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Eyes | The SDS says to get medical attention if any damage to the eye is caused by the metal. |
Handling and storage
- Use strong, cut-resistant gloves suitable for handling metals, as the SDS asks.
- Take care with items that are sharp or heavy.
- Store in accordance with local regulations, and keep the ribbon away from moisture and corrosive materials, which the SDS lists as incompatible.
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%
- Critical mineral lists
- US: not listed
- Recycling
- USGS iron ore chapter: 'None', 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 extensively used for steelmaking in electric arc furnaces and foundries.
Niobium
- Top producers (2025)
- Brazil 92.9%, Canada 5.4%
- Critical mineral lists
- US: listed
- Recycling
- USGS: niobium was recycled with niobium-bearing steels and superalloys, but scrap recovery specifically for niobium content was negligible.
- Substitutes
- USGS: ceramic matrix composites, molybdenum, tantalum and tungsten can replace niobium in high-temperature superalloy applications, with a performance loss or higher cost.
Boron
- Critical mineral lists
- US: listed
Silicon
- Critical mineral lists
- US: listed
Copper
- Critical mineral lists
- US: listed
Chromium
- Critical mineral lists
- US: listed
Manganese
- Critical mineral lists
- US: listed
Documents
Datasheets, safety data sheets, papers and standards you can open.
| Document | Type | Year |
|---|---|---|
| METGLAS Magnetic Alloy 2605S3A (Iron-based) Technical Bulletin | datasheet | 2009 |
| Safety Data Sheet, FT-3W and 2605S3A (Metglas, Inc.) | sds | 2020 |
| METGLAS Magnetic Materials, 2605S3A product section | datasheet | |
| Mineral Commodity Summaries 2026, Iron Ore (USGS) | report | 2026 |
| Mineral Commodity Summaries 2026, Niobium (Columbium) (USGS) | report | 2026 |
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: metglas-2605s3a
spore_version: 0.2
family: magnet-and-superconducting-alloys
name: METGLAS 2605S3A
role: magnetic core ribbon
category: metals
type: magnet-alloys
summary: |
METGLAS 2605S3A is an iron-based amorphous metal ribbon made by Metglas, Inc. Its technical bulletin gives a density of 7.29 g/cm3, a saturation induction of 1.41 T and a Curie temperature of 358 °C. Metglas lists it for current transformers, ground fault protection devices and high-frequency cores.
best_for: High-frequency cores, current transformers and ground fault protection devices, the three applications the manufacturer lists
weakest_at: 'Corrosion data: the SDS lists moisture and corrosive materials as incompatible and prints no corrosion rate'
identity:
formula: 'Iron-based amorphous metal ribbon. The SDS gives composition as percentage ranges: iron 69 to 100, silicon 0 to 10, niobium 0 to 7, boron 0 to 5, chromium 0 to 5, manganese 0 to 2, copper 0 to 2. The basis is not stated, and the SDS says ranges may reflect batch variation.'
source: s3a-sds
where: Section 1, Other means of identification (Amorphous Metal Ribbon); Section 3, Composition table
designations:
- system: Trade name
code: 2605S3A
source: s3a-bulletin
where: Title block, Magnetic Alloy 2605S3A (Iron-based)
- system: Trade name
code: METGLAS Alloy 2605S3A
source: s3a-bulletin
where: Page 2, figure caption
tags:
environments: []
stresses: []
applications:
- electronics-and-chips
properties:
- benchmark: density
label: Density, technical bulletin
value: 7.29
unit: g/cm3
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
condition: as printed; heat-treatment state not stated
method: Value printed in the manufacturer's technical bulletin; the product page prints the same value
status: ground
source: s3a-bulletin
where: Physical Properties column, Density (g/cm3) row
- benchmark: density
label: Relative density, safety data sheet
value: 7
value_high: 7.5
bound: range
unit: '-'
scope: material
conditions:
basis: printed as relative density with water = 1; no unit printed
document: combined FT-3W and 2605S3A SDS, Metglas, Inc.
method: Range printed in the manufacturer's safety data sheet; a dimensionless ratio, so entered with unit -
status: ground
source: s3a-sds
where: Section 9, Relative density row
- benchmark: saturation_induction
label: Saturation induction
value: 1.41
unit: T
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
condition: as printed; heat-treatment state not stated
method: Value printed in the manufacturer's technical bulletin; the product page prints the same value
status: ground
source: s3a-bulletin
where: Magnetic Properties column, Saturation Induction (T) row
- benchmark: dc_permeability
label: Maximum DC permeability, annealed
value: 35000
unit: '-'
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
heat_treatment: annealed
method: Value printed in the manufacturer's technical bulletin, which gives the symbol mu with no unit; entered as a dimensionless relative permeability
status: ground
source: s3a-bulletin
where: Magnetic Properties column, Maximum D.C. Permeability, Annealed row
- benchmark: dc_permeability
label: Maximum DC permeability, as cast
value: 20000
bound: lower
unit: '-'
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
heat_treatment: as cast
method: Minimum printed in the manufacturer's technical bulletin as greater than 20,000, with no unit; entered as a dimensionless relative permeability
status: ground
source: s3a-bulletin
where: Magnetic Properties column, Maximum D.C. Permeability, As Cast row
- benchmark: magnetostriction
label: Saturation magnetostriction
value: 20
unit: ppm
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
method: Value printed in the manufacturer's technical bulletin
status: ground
source: s3a-bulletin
where: Magnetic Properties column, Saturation Magnetostriction (ppm) row
- benchmark: electrical_resistivity
label: Electrical resistivity
value: 138
unit: µΩ-cm
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
temperature: not stated
method: Value printed on the manufacturer's product page; the bulletin prints the same value
status: ground
note: The bulletin's text layer shows the unit as µ-cm; the product page prints µΩ-cm.
source: metglas-web
where: 2605S3A product section, Electromagnetic list, Electrical Resistivity (µΩ-cm)
- benchmark: curie_temperature
label: Curie temperature
value: 358
unit: °C
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
method: Value printed in the manufacturer's technical bulletin; the product page prints the same value
status: ground
source: s3a-bulletin
where: Magnetic Properties column, Curie Temperature (°C) row
- benchmark: thickness
label: Ribbon thickness
value: 18
unit: microns
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
printed_as: Thickness (microns) 18
method: Value printed on the manufacturer's product page; the technical bulletin does not give a thickness
status: ground
source: metglas-web
where: 2605S3A product section, Physical list, Thickness (microns)
- benchmark: ultimate_tensile_strength
label: Tensile strength
value: 1
value_high: 2
bound: range
unit: GPa
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
printed_as: 1-2
condition: heat-treatment state not stated
method: Range printed in the manufacturer's technical bulletin; the product page prints the same range
status: ground
source: s3a-bulletin
where: Physical Properties column, Tensile Strength (GPa) row
- benchmark: elastic_modulus
label: Elastic modulus
value: 100
value_high: 110
bound: range
unit: GPa
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
printed_as: 100-110
method: Range printed in the manufacturer's technical bulletin; the product page prints the same range
status: ground
source: s3a-bulletin
where: Physical Properties column, Elastic Modulus (GPa) row
- benchmark: lamination_factor
label: Lamination factor
value: 75
bound: lower
unit: '%'
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
printed_as: '>75'
method: Minimum printed in the manufacturer's technical bulletin
status: ground
source: s3a-bulletin
where: Physical Properties column, Lamination Factor (%) row
- benchmark: cte
label: Coefficient of thermal expansion
value: 6.7
unit: ppm/°C
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
temperature_range: not printed in the bulletin
method: Value printed in the manufacturer's technical bulletin
status: ground
source: s3a-bulletin
where: Physical Properties column, Thermal Expansion (ppm/°C) row
- benchmark: crystallization_temperature
label: Crystallization temperature
value: 535
unit: °C
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
method: Value printed in the manufacturer's technical bulletin; the bulletin does not say what happens to properties above it
status: ground
source: s3a-bulletin
where: Physical Properties column, Crystallization Temperature (°C) row
- benchmark: max_service_temp
label: Continuous service temperature
value: 150
unit: °C
scope: material
conditions:
grade: METGLAS Alloy 2605S3A ribbon
basis: continuous service temperature as printed
method: Value printed in the manufacturer's technical bulletin; the product page prints the same value
status: ground
source: s3a-bulletin
where: Physical Properties column, Continuous Service Temp. (°C) row
- benchmark: melting_point
label: Melting point
value: 1180
unit: °C
scope: material
conditions:
document: combined FT-3W and 2605S3A SDS
printed_as: 1180°C (2156°F)
method: Value printed in the manufacturer's safety data sheet, which covers two products in one document
status: ground
source: s3a-sds
where: Section 9, Melting point row
corrosion:
- environment: Moisture and corrosive materials (storage and incompatibilities)
headline: The SDS lists moisture and corrosive materials as incompatible with the product.
effect: The SDS gives no corrosion rate, test result or exposure time for the ribbon.
rating: unknown
source: s3a-sds
where: Section 10, Incompatible materials
- environment: Heating near the crystallization temperature (thermal ageing)
headline: The bulletin prints a crystallization temperature of 535 °C and a continuous service temperature of 150 °C.
effect: The sources read give no ageing or property-change data after long heating at these temperatures.
rating: unknown
source: s3a-bulletin
where: Physical Properties column, Crystallization Temperature and Continuous Service Temp. rows
risks:
hazards:
- text: The SDS says the product is not classified under the OSHA Hazard Communication Standard and has no GHS signal word or hazard statements.
ghs: []
source: s3a-sds
where: Section 2, OSHA/HCS status and GHS label elements
- text: The SDS says adverse symptoms may include metal fume fever if exposed to high concentrations of fumes.
ghs: []
source: s3a-sds
where: Section 11, Other information
- text: The SDS classification table gives chromium, one of the listed ingredients, an IARC entry printed as "3".
ghs: []
source: s3a-sds
where: Section 11, Classification table; Section 3, Composition
- text: The SDS lists manganese under specific target organ toxicity from repeated exposure as "Category 2", with target organs central nervous system (CNS) and lungs.
ghs: []
source: s3a-sds
where: Section 11, Specific target organ toxicity (repeated exposure)
failure_risks:
- mode: Melting or burning of the ribbon
trigger: Heating to the melting point, or a structural fire
consequence: The SDS gives a melting point of 1180 °C and says decomposition products may include metal oxides and toxic vapour.
severity: moderate
source: s3a-sds
where: Section 5, Hazardous thermal decomposition products; Section 9, Melting point
- mode: Heating above the crystallization temperature
trigger: Exposure above 535 °C
consequence: The bulletin prints the crystallization temperature but states no property change above it.
severity: moderate
source: s3a-bulletin
where: Physical Properties column, Crystallization Temperature row
- mode: Attack by moisture or corrosive materials
trigger: Storage or use with moisture or corrosive materials
consequence: The SDS lists both as incompatible with the product; no damage rate is printed.
severity: low
source: s3a-sds
where: Section 10, Incompatible materials
side_effects:
- text: The SDS says to get medical attention if any damage to the eye is caused by the metal.
affects: Eyes
source: s3a-sds
where: Section 4, Eye contact
handling:
- text: Use strong, cut-resistant gloves suitable for handling metals, as the SDS asks.
source: s3a-sds
where: Section 8, Hand protection
- text: Take care with items that are sharp or heavy.
source: s3a-sds
where: Section 7, Precautions for safe handling
- text: Store in accordance with local regulations, and keep the ribbon away from moisture and corrosive materials, which the SDS lists as incompatible.
source: s3a-sds
where: Section 7, Conditions for safe storage; Section 10, Incompatible materials
uses:
- application: electronics-and-chips
device: Current transformers
example: The manufacturer's application list for 2605S3A names current transformers.
source: s3a-bulletin
where: Page 1, Applications list
- application: electronics-and-chips
device: Ground fault protection devices
example: The same application list names ground fault protection devices.
source: s3a-bulletin
where: Page 1, Applications list
- application: electronics-and-chips
device: High-frequency cores
example: The benefits list reads "Low core loss at high frequencies (>1 kHz)", and the application list names high frequency cores.
source: s3a-bulletin
where: Page 1, Applications and Benefits lists
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:
- list: USGS 2025 List of Critical Minerals
listed: false
recycling: 'USGS iron ore chapter: ''None'', 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 extensively used for steelmaking in electric arc furnaces and foundries.'
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 from those values; Recycling; Substitutes
- subject: Niobium
producers:
- country: Brazil
share_percent: 92.9
year: 2025
- country: Canada
share_percent: 5.4
year: 2025
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
recycling: 'USGS: niobium was recycled with niobium-bearing steels and superalloys, but scrap recovery specifically for niobium content was negligible.'
substitutes:
- 'USGS: ceramic matrix composites, molybdenum, tantalum and tungsten can replace niobium in high-temperature superalloy applications, with a performance loss or higher cost.'
source: usgs-mcs2026-niobium
where: World Mine Production and Reserves table, 2025e (world total 112,000 in niobium content; shares calculated by Space Mushroom); Recycling; Substitutes. Critical list status from the USGS 2025 list page.
- subject: Boron
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
source: usgs-mcs2026-iron
where: Iron ore chapter, World Mine Production and Reserves paragraph on the final 2025 list (boron added)
- subject: Silicon
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
source: usgs-mcs2026-iron
where: Iron ore chapter, World Mine Production and Reserves paragraph on the final 2025 list (silicon added)
- subject: Copper
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
source: usgs-mcs2026-iron
where: Iron ore chapter, World Mine Production and Reserves paragraph on the final 2025 list (copper added)
- subject: Chromium
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
source: usgs-crit2025
where: Explore the 2025 List of Critical Minerals section
- subject: Manganese
critical_lists:
- list: USGS 2025 List of Critical Minerals
listed: true
source: usgs-crit2025
where: Explore the 2025 List of Critical Minerals section
documents:
- title: METGLAS Magnetic Alloy 2605S3A (Iron-based) Technical Bulletin
type: datasheet
url: https://metglas.com/wp-content/uploads/2021/06/2605S3A-Magnetic-Alloy-updated.pdf
year: 2009
- title: Safety Data Sheet, FT-3W and 2605S3A (Metglas, Inc.)
type: sds
url: https://metglas.com/wp-content/uploads/2021/03/FT-3W-and-2605S3A_SDSFinal.pdf
year: 2020
- title: METGLAS Magnetic Materials, 2605S3A product section
type: datasheet
url: https://metglas.com/magnetic-materials/
- 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, Niobium (Columbium) (USGS)
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-niobium.pdf
year: 2026
gaps:
- 'No core-loss value is printed for 2605S3A: the bulletin shows a core-loss curve as an image, and the product page gives only a graph.'
- The Vickers hardness row is printed without a unit in the bulletin and on the product page, so no value is recorded.
- No UNS, ASTM, EN, DIN, JIS or AISI designation for 2605S3A is printed in the sources read; only the trade names 2605S3A and METGLAS Alloy 2605S3A are listed.
- The SDS covers FT-3W and 2605S3A in one document. Its composition, melting point and hazard entries are not split by product.
- The SDS composition table gives percentage ranges without saying whether they are weight or atomic percent.
- Chromium, manganese and copper have no producer shares in this profile; the USGS iron ore and niobium chapters do not cover them.
- No magnetic relaxation, field-anneal or forming data are printed for 2605S3A in the sources read.
- No vacuum, cryogenic, radiation or flight data for 2605S3A were found in the sources read.
- The DC permeability rows carry no unit in the source, so they are entered as dimensionless values.
- Several benchmark names, such as lamination_factor and crystallization_temperature, are outside the canonical list because no canonical name fits.
- The ASM Alloy Digest entry for 2605S3A is behind a paywall; only its abstract was read, and it gives no values.
- PubChem could not be read in this run (browser check page), so hazard data rest on the SDS alone.
sources:
s3a-bulletin:
title: METGLAS Magnetic Alloy 2605S3A (Iron-based) Technical Bulletin
id: ref 2605S3A03112009; copyright 2003-2009
url: https://metglas.com/wp-content/uploads/2021/06/2605S3A-Magnetic-Alloy-updated.pdf
year: 2009
kind: datasheet
license: manufacturer document, linked not reproduced
s3a-sds:
title: Safety Data Sheet, FT-3W and 2605S3A (Metglas, Inc.)
id: Date of issue 07/17/2020, version 1; combined document for two products
url: https://metglas.com/wp-content/uploads/2021/03/FT-3W-and-2605S3A_SDSFinal.pdf
year: 2020
kind: datasheet
license: supplier document, linked not reproduced
metglas-web:
title: METGLAS Magnetic Materials, 2605S3A section (General Properties and Characteristics)
id: Metglas, Inc. product page, undated
url: https://metglas.com/magnetic-materials/
kind: web
license: manufacturer web page, linked not reproduced
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-niobium:
title: Mineral Commodity Summaries 2026, Niobium (Columbium)
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-niobium.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-crit2025:
title: About the 2025 List of Critical Minerals (USGS)
id: Final 2025 List of Critical Minerals, November 2025
url: https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals
year: 2025
kind: web
license: public domain (USGS)
wiki-metallic-glass:
title: Metallic glass (Wikipedia)
id: English Wikipedia article, Metallic glass
url: https://en.wikipedia.org/wiki/Metallic_glass
kind: web
license: CC BY-SA
asm-fe157:
title: METGLAS ALLOY 2605S3A Magnetic Alloy, ASM Alloy Digest Fe-157 (abstract only)
id: ASM Alloy Digest, filing code Fe-157
url: https://dl.asminternational.org/alloy-digest/article/60/11/Fe-157/7416/METGLAS-ALLOY-2605S3AMagnetic-Alloy
kind: handbook
license: ASM Digital Library, abstract read
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 16
unreachable: 1
caveats: 2
note: Read by an AI assistant on 2026-11-01 from the technical bulletin, SDS, product page, USGS chapters and USGS critical-minerals page, all fetched in this run; values copied as printed. Vickers hardness left out (no unit printed). Supply shares calculated from the USGS tables.
story:
recipe:
line: METGLAS 2605S3A is an iron-based ribbon. The safety data sheet lists its ingredients as percentage ranges rather than a fixed formula. Amorphous metals are non-crystalline with a glass-like structure, according to the Wikipedia article on metallic glass, and the SDS gives 'Amorphous Metal Ribbon' as the product's other name.
parts:
- name: Iron
symbol: Fe
share_percent: 69
share_high: 100
role: Main constituent; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Silicon
symbol: Si
share_percent: 0
share_high: 10
role: Alloying element; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Niobium
symbol: Nb
share_percent: 0
share_high: 7
role: Alloying element; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Boron
symbol: B
share_percent: 0
share_high: 5
role: Ingredient listed in the SDS; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Chromium
symbol: Cr
share_percent: 0
share_high: 5
role: Ingredient listed in the SDS; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Manganese
symbol: Mn
share_percent: 0
share_high: 2
role: Ingredient listed in the SDS; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
- name: Copper
symbol: Cu
share_percent: 0
share_high: 2
role: Ingredient listed in the SDS; the SDS gives a range.
source: s3a-sds
where: Section 3, Composition table
risk_groups:
- title: For people
level: 1
verdict: Not classified under OSHA HCS
lead: The safety data sheet says the ribbon is not considered hazardous under the OSHA Hazard Communication Standard. Its sharp or heavy edges are the practical hazard.
points:
- label: Edges and weight
line: The SDS asks for care with items that are sharp or heavy, and for cut-resistant gloves.
- label: Fumes
line: The SDS notes that metal fume fever may follow exposure to high concentrations of fumes.
- label: Ingredients
line: The SDS lists chromium with an IARC entry printed as 3, and manganese as a repeated-exposure hazard in Category 2, affecting the central nervous system and lungs.
- title: If the ribbon melts or burns
level: 2
verdict: Toxic vapour and metal oxides
lead: These points come from the SDS and the bulletin, not from field incidents.
points:
- label: Melting point
line: The SDS gives a melting point of 1180 °C. Decomposition products may include metal oxides and toxic vapour.
- label: Crystallization
line: The bulletin gives a crystallization temperature of 535 °C but does not say what happens to the ribbon's properties above it.
- title: Handling and storage
points:
- label: Storage
line: The SDS says to store the ribbon according to local regulations, and to check Section 10 for incompatible materials, which include moisture and corrosive materials.
- label: Service temperature
line: The bulletin gives a continuous service temperature of 150 °C.
why: METGLAS 2605S3A is an iron-based amorphous metal ribbon made by Metglas, Inc. The safety data sheet names it as an amorphous metal ribbon for the electrical industry. The manufacturer's bulletin lists it for current transformers, ground fault protection devices and high-frequency cores. The bulletin claims a high operating temperature with minimal flux density reduction, and the ASM Alloy Digest abstract calls it an iron-base alloy with high permeability.
uses:
- where: Current transformers and ground fault protection
line: The manufacturer's bulletin names current transformers and ground fault protection devices as applications for 2605S3A.
- where: High-frequency cores
line: The bulletin lists high-frequency cores as an application and gives as a benefit "Low core loss at high frequencies (>1 kHz)".
can_do:
- label: Saturation induction
benchmark: saturation_induction
line: The bulletin gives a saturation induction of 1.41 T for the ribbon.
- label: Permeability
benchmark: dc_permeability
value: 35,000 annealed; above 20,000 as cast
line: The bulletin gives a maximum DC permeability of 35,000 when annealed and above 20,000 as cast. It prints no unit for this value, so the profile enters it as a dimensionless number.
- label: Continuous temperature
benchmark: max_service_temp
value: 150 °C
line: The bulletin gives a continuous service temperature of 150 °C.
- label: Lamination
benchmark: lamination_factor
line: The bulletin gives a lamination factor above 75 %, which the profile records as a lower bound.
compare: The sources read do not compare METGLAS 2605S3A with other magnetic alloys. Within its own bulletin the density is 7.29 g/cm3 and the Curie temperature is 358 °C, and the product page prints the same values. The product page lists 2605S3A alongside other Metglas alloys, but this profile records only the values printed for 2605S3A itself.
compare_rows:
- label: Density
benchmark: density
- label: Saturation induction
benchmark: saturation_induction
- label: Curie temperature
benchmark: curie_temperature
handling:
- Wear strong, cut-resistant gloves suitable for handling metals, as the SDS asks.
- Take care with items that are sharp or heavy.
- Keep the ribbon away from moisture and corrosive materials, which the SDS lists as incompatible.
- Wash hands and face before eating, drinking and smoking, as the SDS advises.
good_for:
- Current transformers and ground fault protection devices, two of the three applications in the manufacturer's bulletin.
- High-frequency cores, where the manufacturer claims a high operating temperature with minimal flux density reduction.
watch_out:
- 'No core-loss value is printed for this grade: the bulletin shows a core-loss curve as an image only.'
- No corrosion rate is printed; the SDS lists moisture and corrosive materials as incompatible.
- The SDS covers FT-3W and 2605S3A in one document, so its composition, melting point and hazard entries may not apply to 2605S3A alone.
- Magnetic relaxation after a change in field, and forming behaviour, are not documented for this grade in the sources read.
verdict: METGLAS 2605S3A is a documented iron-based amorphous ribbon for high-frequency cores, current transformers and ground fault protection devices. Its bulletin and product page print the same values. Its core loss, corrosion behaviour and long-term magnetic stability 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 Magnetic Alloy 2605S3A (Iron-based) Technical Bulletin | datasheet | 2009 | 17 values | |
| Safety Data Sheet, FT-3W and 2605S3A (Metglas, Inc.) | datasheet | 2020 | 14 values | |
| METGLAS Magnetic Materials, 2605S3A section (General Properties and Characteristics) | web | 2 values | ||
| Mineral Commodity Summaries 2026, Iron Ore | report | 2026 | 4 values | |
| Mineral Commodity Summaries 2026, Niobium (Columbium) | report | 2026 | 1 value | |
| About the 2025 List of Critical Minerals (USGS) | web | 2025 | 2 values | |
| Metallic glass (Wikipedia) | web | 0 values | ||
| METGLAS ALLOY 2605S3A Magnetic Alloy, ASM Alloy Digest Fe-157 (abstract only) | handbook | 0 values |
Updated