spore: profile
id: alsic
spore_version: 0.2
family: aluminium-silicon-carbide
name: Aluminium silicon carbide (AlSiC) metal-matrix composite
abbreviation: AlSiC
role: thermal-management substrate, heat spreader and hermetic housing
category: composites
type: metal-matrix
summary: Aluminium silicon carbide (AlSiC) is a metal-matrix composite of an aluminium alloy (alloy 356 in the CPS Technologies grades) reinforced with silicon carbide (SiC) particles. CPS Technologies prints a density of 3.01 g/cm3 and a thermal conductivity of 190 W/mK typical at 25 °C for the AlSiC-9 grade, which is 37% vol aluminium alloy and 63% vol silicon carbide. The same grade has a coefficient of thermal expansion of 8.00 ppm/°C from 30 to 100 °C, and Wikipedia says the expansion can be tuned to match silicon, gallium arsenide and several ceramics.
best_for: Matching the thermal expansion of silicon, gallium arsenide or ceramic chips while spreading heat in power electronics, in a material of 2.89 to 3.01 g/cm3 (AlSiC-12 to AlSiC-9)
weakest_at: 'Ductility: 11.3 MPa/m2 fracture toughness and 0.295 percent elongation at rupture for AlSiC-9 (CPS 2025), and silicon carbide dust that PubChem lists with a cancer-by-inhalation hazard statement'
identity:
  formula: Composite of aluminium alloy 356 (matrix) and silicon carbide particles (reinforcement); AlSiC-9 is 37% vol aluminium alloy 356 and 63% vol silicon carbide (CPS 2025 slide)
  cas: 409-21-2 (silicon carbide reinforcement, PubChem CID 9863; the composite has no CAS number in the sources read)
  source: cps-alsic-2025
  where: Select Material Properties table, rows Aluminum Alloy 356 and Silicon Carbide
  designations:
    - system: Trade name
      code: AlSiC-9
      source: cps-alsic-2025
      where: Select Material Properties table, column AlSiC-9
    - system: Trade name
      code: AlSiC-10
      source: wikipedia-alsic
      where: Grades list, AlSiC-10 entry
    - system: Trade name
      code: AlSiC-12
      source: cps-alsic-2025
      where: Select Material Properties table, column AlSiC-12
tags:
  environments: []
  stresses: []
  applications:
    - electronics-and-chips
    - thermal-control
    - optics-and-cameras
    - rovers-and-surface-systems
properties:
  - benchmark: density
    label: Density, AlSiC-9 (CPS 2025)
    value: 3.01
    unit: g/cm3
    scope: material
    conditions:
      grade: AlSiC-9
      composition: 37% vol aluminium alloy 356, 63% vol SiC
      temperature: not stated on the slide
      printed: '3.01'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Density (g/cm3) row, AlSiC-9 column
  - benchmark: density
    label: Density, AlSiC-12 (CPS 2025)
    value: 2.89
    unit: g/cm3
    scope: material
    conditions:
      grade: AlSiC-12
      composition: 63% vol aluminium alloy 356, 37% vol SiC
      temperature: not stated on the slide
      printed: '2.89'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Density (g/cm3) row, AlSiC-12 column
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-9, typical (CPS 2025)
    value: 190
    unit: W/mK
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 25 °C
      basis: typical
      printed: 190 typical
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Conductivity @25°C (W/mK) row, AlSiC-9 column, typical value
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-9, minimum (CPS 2025)
    value: 180
    unit: W/mK
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 25 °C
      basis: minimum
      printed: 180 min
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Conductivity @25°C (W/mK) row, AlSiC-9 column, minimum value
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-12, typical (CPS 2025)
    value: 180
    unit: W/mK
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 25 °C
      basis: typical
      printed: 180 typical
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Conductivity @25°C (W/mK) row, AlSiC-12 column, typical value
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-12, minimum (CPS 2025)
    value: 170
    unit: W/mK
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 25 °C
      basis: minimum
      printed: 170 min
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Conductivity @25°C (W/mK) row, AlSiC-12 column, minimum value
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-9, 30-100 °C (CPS 2025)
    value: 8
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 30-100 °C
      printed: '8.00'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-100°C line, AlSiC-9 column
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-9, 30-150 °C (CPS 2025)
    value: 8.37
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 30-150 °C
      printed: '8.37'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-150°C line, AlSiC-9 column
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-9, 30-200 °C (CPS 2025)
    value: 8.75
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 30-200 °C
      printed: '8.75'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-200°C line, AlSiC-9 column
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-12, 30-100 °C (CPS 2025)
    value: 10.9
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 30-100 °C
      printed: '10.90'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-100°C line, AlSiC-12 column
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-12, 30-150 °C (CPS 2025)
    value: 11.2
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 30-150 °C
      printed: '11.20'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-150°C line, AlSiC-12 column
  - benchmark: cte
    label: Coefficient of thermal expansion, AlSiC-12, 30-200 °C (CPS 2025)
    value: 11.7
    unit: ppm/°C
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 30-200 °C
      printed: '11.70'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Thermal Expansion (CTE) row, 30-200°C line, AlSiC-12 column
  - benchmark: specific_heat
    label: Specific heat, AlSiC-9 (CPS 2025)
    value: 0.741
    unit: J/gK
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: 25 °C
      printed: '0.741'
    method: Value printed in a manufacturer product slide; unit printed as J/gK
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Specific Heat @25°C (J/gK) row, AlSiC-9 column
  - benchmark: specific_heat
    label: Specific heat, AlSiC-12 (CPS 2025)
    value: 0.808
    unit: J/gK
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: 25 °C
      printed: '0.808'
    method: Value printed in a manufacturer product slide; unit printed as J/gK
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Specific Heat @25°C (J/gK) row, AlSiC-12 column
  - benchmark: elastic_modulus
    label: Young's modulus, AlSiC-9 (CPS 2025)
    value: 188
    unit: GPa
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the slide
      printed: '188'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Young's Modulus (GPa) row, AlSiC-9 column
  - benchmark: elastic_modulus
    label: Young's modulus, AlSiC-12 (CPS 2025)
    value: 167
    unit: GPa
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: not stated on the slide
      printed: '167'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Young's Modulus (GPa) row, AlSiC-12 column
  - benchmark: shear_modulus
    label: Shear modulus, AlSiC-9 (CPS 2025)
    value: 76
    unit: GPa
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the slide
      printed: '76'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Shear Modulus (GPa) row, AlSiC-9 column
  - benchmark: shear_modulus
    label: Shear modulus, AlSiC-12 (CPS 2025)
    value: 69
    unit: GPa
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: not stated on the slide
      printed: '69'
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Shear Modulus (GPa) row, AlSiC-12 column
  - benchmark: flexural_strength
    label: Four-point bend strength, AlSiC-9 (CPS 2025)
    value: 488
    unit: MPa
    scope: material
    conditions:
      grade: AlSiC-9
      test: four-point bend, printed as A-Bar 4-pt Bend Strength
      temperature: not stated on the slide
      printed: '488'
    method: Value printed in a manufacturer product slide; the slide does not use the word flexural
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, A-Bar 4-pt Bend Strength (MPa) row, AlSiC-9 column
  - benchmark: flexural_strength
    label: Four-point bend strength, AlSiC-12 (CPS 2025)
    value: 471
    unit: MPa
    scope: material
    conditions:
      grade: AlSiC-12
      test: four-point bend, printed as A-Bar 4-pt Bend Strength
      temperature: not stated on the slide
      printed: '471'
    method: Value printed in a manufacturer product slide; the slide does not use the word flexural
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, A-Bar 4-pt Bend Strength (MPa) row, AlSiC-12 column
  - benchmark: fracture_toughness
    label: Fracture toughness, AlSiC-9 (CPS 2025)
    value: 11.3
    unit: MPa/m2
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the slide
      printed: '11.3'
      note: name is not in the canonical list; see gaps
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Fracture Toughness (MPa/m2) row, AlSiC-9 column
  - benchmark: elongation
    label: Percent elongation at rupture, AlSiC-9 (CPS 2025)
    value: 0.295
    unit: '%'
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the slide
      printed: '0.295'
      unit_in_source: row name Percent Elongation at Rupture, no unit printed beyond the name
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Percent Elongation at Rupture row, AlSiC-9 column
  - benchmark: electrical_resistivity
    label: Electrical resistance, AlSiC-9, printed in microohm-cm (CPS 2025)
    value: 20.7
    unit: µOhm-cm
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the slide
      printed: '20.7'
      note: printed as Electrical Resistance; see gaps
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Electrical Resistance (µOhm-cm) row, AlSiC-9 column
  - benchmark: electrical_resistivity
    label: Electrical resistance, AlSiC-12, printed in microohm-cm (CPS 2025)
    value: 20.7
    unit: µOhm-cm
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: not stated on the slide
      printed: '20.7'
      note: printed as Electrical Resistance; see gaps
    method: Value printed in a manufacturer product slide
    status: ground
    source: cps-alsic-2025
    where: Select Material Properties table, Electrical Resistance (µOhm-cm) row, AlSiC-12 column
  - benchmark: density
    label: Density, Al75/SiC25 (Ferrotec)
    value: 2.8
    unit: g/cm3
    scope: material
    conditions:
      composition: Al 75 vol%, SiC 25 vol%
      temperature: not stated on the page
      printed: '2.8'
    method: Value printed on a manufacturer product web page
    status: ground
    source: ferrotec-alsic
    where: Al / SiC Material Properties table, Density (g/cm3) row, Al75 / SiC25 column
  - benchmark: density
    label: Density, Al70/SiC30 (Ferrotec)
    value: 2.8
    unit: g/cm3
    scope: material
    conditions:
      composition: Al 70 vol%, SiC 30 vol%
      temperature: not stated on the page
      printed: '2.8'
    method: Value printed on a manufacturer product web page
    status: ground
    source: ferrotec-alsic
    where: Al / SiC Material Properties table, Density (g/cm3) row, Al70 / SiC30 column
  - benchmark: density
    label: Density, Al60/SiC40 (Ferrotec)
    value: 2.9
    unit: g/cm3
    scope: material
    conditions:
      composition: Al 60 vol%, SiC 40 vol%
      temperature: not stated on the page
      printed: '2.9'
    method: Value printed on a manufacturer product web page
    status: ground
    source: ferrotec-alsic
    where: Al / SiC Material Properties table, Density (g/cm3) row, Al60 / SiC40 column
  - benchmark: cte
    label: Coefficient of thermal expansion, Al75/SiC25 (Ferrotec)
    value: 15
    unit: ppm/°C
    scope: material
    conditions:
      composition: Al 75 vol%, SiC 25 vol%
      temperature: not stated on the page
      printed: '15'
      unit_in_source: 1/°C×10-6
    method: Value printed on a manufacturer product web page
    status: ground
    source: ferrotec-alsic
    where: Al / SiC Material Properties table, Coefficient of thermal expansion row, Al75 / SiC25 column
  - benchmark: cte
    label: Coefficient of thermal expansion, Al60/SiC40 (Ferrotec)
    value: 13
    unit: ppm/°C
    scope: material
    conditions:
      composition: Al 60 vol%, SiC 40 vol%
      temperature: not stated on the page
      printed: '13'
      unit_in_source: 1/°C×10-6
    method: Value printed on a manufacturer product web page
    status: ground
    source: ferrotec-alsic
    where: Al / SiC Material Properties table, Coefficient of thermal expansion row, Al60 / SiC40 column
  - benchmark: density
    label: Density, AlSiC-10 at 25 °C (Wikipedia)
    value: 2.96
    unit: g/cm3
    scope: material
    conditions:
      grade: AlSiC-10
      composition: 45 vol% A 356.2 aluminium alloy, 55 vol% SiC
      temperature: 25 °C
      printed: '2.96'
    method: Value printed in a Wikipedia article that cites manufacturer data
    status: ground
    source: wikipedia-alsic
    where: Grades list, AlSiC-10 entry
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-10 (Wikipedia)
    value: 190
    value_high: 200
    unit: W/m K
    scope: material
    conditions:
      grade: AlSiC-10
      temperature: not stated on the page
      printed: 190-200
    method: Range printed in a Wikipedia article that cites manufacturer data
    status: ground
    source: wikipedia-alsic
    where: Grades list, AlSiC-10 entry
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-9 (Wikipedia)
    value: 190
    value_high: 200
    unit: W/m K
    scope: material
    conditions:
      grade: AlSiC-9
      temperature: not stated on the page
      printed: 190-200
    method: Range printed in a Wikipedia article that cites manufacturer data
    status: ground
    source: wikipedia-alsic
    where: Grades list, AlSiC-9 entry
  - benchmark: thermal_conductivity
    label: Thermal conductivity, AlSiC-12 (Wikipedia)
    value: 170
    value_high: 180
    unit: W/m K
    scope: material
    conditions:
      grade: AlSiC-12
      temperature: not stated on the page
      printed: 170-180
    method: Range printed in a Wikipedia article that cites manufacturer data
    status: ground
    source: wikipedia-alsic
    where: Grades list, AlSiC-12 entry
corrosion: []
risks:
  hazards:
    - text: PubChem reports for silicon carbide (CID 9863) list H350i, May cause cancer by inhalation, with signal word Danger. The ECHA C&L aggregation says 740 of 1053 company reports did not meet GHS hazard criteria, and the record notes that classification varies with impurities, additives and form.
      ghs:
        - H350i
      source: pubchem-sic
      where: GHS Classification section, aggregated ECHA C&L notifications
    - text: 'PubChem quotes IARC Vol. 111: occupational exposures in the Acheson process are Group 1, fibrous silicon carbide is Group 2B, and silicon carbide whiskers are Group 2A. PubChem also quotes ACGIH: silicon carbide fibres should be controlled like asbestos fibres, while nonfibrous particles have low to very low toxic effects on lung tissue.'
      ghs: []
      source: pubchem-sic
      where: Hazards Summary section, quoting IARC Vol. 111 and ACGIH
    - text: 'PubChem quotes the NIOSH Pocket Guide for silicon carbide: exposure by inhalation, ingestion, skin or eye contact, with symptoms of irritation of the eyes, skin and upper respiratory system, and cough.'
      ghs: []
      source: pubchem-sic
      where: Health Hazards section, NIOSH Pocket Guide excerpt
  failure_risks:
    - mode: Brittle fracture under high load
      trigger: Stress approaching the four-point bend strength of 488 MPa for AlSiC-9
      consequence: The 2025 CPS slide prints a fracture toughness of 11.3 MPa/m2 and a percent elongation at rupture of 0.295 for AlSiC-9. The slide gives no further failure data.
      severity: moderate
      source: cps-alsic-2025
      where: Select Material Properties table, Fracture Toughness and Percent Elongation at Rupture rows
    - mode: Thermal expansion mismatch from the wrong grade
      trigger: Attaching AlSiC to a chip or substrate whose expansion differs from the grade chosen
      consequence: CPS prints 8.00 ppm/°C for AlSiC-9 and 10.90 ppm/°C for AlSiC-12 at 30-100 °C, so the grade sets the match. The sources read give no stress or fatigue data for a mismatched joint.
      severity: moderate
      source: cps-alsic-2025
      where: Select Material Properties table, Thermal Expansion (CTE) row, 30-100°C line
  side_effects:
    - text: Silicon carbide dust from machining is the handling concern named in the sources; the CPS sheet itself names no side effect of the composite.
      affects: Workers who cut, grind or drill AlSiC parts
      source: pubchem-sic
      where: Hazards Summary section, IARC Vol. 111 and ACGIH entries
  handling:
    - text: 'Name the grade on every drawing: AlSiC-9, AlSiC-10 and AlSiC-12 differ in thermal expansion, conductivity and density, per the CPS 2025 slide and Wikipedia.'
      source: cps-alsic-2025
      where: Select Material Properties table
    - text: Control dust when cutting, grinding or drilling AlSiC. The IARC concern is fibrous silicon carbide, and PubChem quotes NIOSH for eye, skin and airway irritation from the silicon carbide dust.
      source: pubchem-sic
      where: Hazards Summary and Health Hazards sections
    - text: 'Surface finish: Wikipedia says AlSiC can be plated with nickel or nickel-gold, or coated with other metals by thermal spraying. The sources read give no plating or corrosion test data.'
      source: wikipedia-alsic
      where: Manufacturing paragraph
    - text: 'Plating compatibility: CPS says its AlSiC pin fin coolers support standard solderable plating schemes and Copper Cold Gas Spray. That sheet gives no corrosion result for any plated finish.'
      source: cps-pinfin
      where: Feature list, bullet on plating schemes
  mitigations: []
uses:
  - application: electronics-and-chips
    device: Power semiconductor base plates and flip-chip lids
    example: The CPS 2025 slide lists IGBTs for Traction, HVDC Transmission, Flip Chip Lids, Microprocessors, Traction Invertors and Optical Benches as applications. Wikipedia says AlSiC is mainly used in microelectronics as a substrate for power semiconductor devices.
    source: cps-alsic-2025
    where: Applications box
  - application: thermal-control
    device: Pin-fin and single-piece coolers for power electronics
    example: The CPS 2025 slide shows a pin-fin cooler for power electronics and describes a single-piece AlSiC cooler with integrated channels, with no welding, brazing or gaskets.
    source: cps-alsic-2025
    where: Applications box and Single Piece Cooler section
  - application: electronics-and-chips
    device: Hermetic packages for military, aerospace and communications systems
    example: The CPS hermetic packaging datasheet lists military, aerospace and communications systems subject to shock and vibration, and says AlSiC is 40-60% lighter than CuMo and CuW.
    source: cps-hp-datasheet
    where: Advantages and Applications lists
  - application: rovers-and-surface-systems
    device: Hermetic housing for an instrument power supply on the Perseverance rover
    example: CPS states, in its company history (2020 entry), that it produced the AlSiC hermetic housing for the turret power supply of the SHERLOC instrument. This is a vendor statement.
    source: cps-history
    where: Our History page, 2020 entry
  - application: electronics-and-chips
    device: Hermetic package for GPS satellite electronics
    example: CPS's company history lists a 2009 entry, CPS introduces a new AlSiC Hermetic Package GPS Satellite, and says AlSiC is also in the International Space Station and in the most recent generation of GPS satellites. These are vendor statements.
    source: cps-history
    where: Our History page, 2009 entry and the sentence on the International Space Station
supply:
  - subject: Primary aluminium, the matrix metal
    note: 'USGS 2026: world smelter production was 74,000 thousand metric tons in 2025e, of which China 45,000 and the United States 660. United States net import reliance was 60 percent of apparent consumption in 2025e. Canada supplied 56 percent of U.S. aluminium imports in 2021-24.'
    producers: []
    critical_lists: []
    recycling: 'USGS 2026: aluminum recovered from purchased scrap in the United States was about 3.6 million tons in 2025, of which about 56% came from new scrap and 44% from old scrap.'
    substitutes: []
    source: usgs-mcs2026-aluminum
    where: Salient Statistics table, World Smelter Production table, Import Sources and Recycling paragraphs
  - subject: AlSiC composites (manufacturers named in the sources)
    note: CPS Technologies, 111 S. Worcester Street, Norton, MA 02766, prints this address on its 2025 AlSiC slide. Ferrotec Advanced Ceramics publishes an Al-SiC product page; its location is not stated on the page.
    producers: []
    critical_lists: []
    recycling: ''
    substitutes: []
    source: cps-alsic-2025
    where: Closing contact block of the 2025 slide
story:
  recipe:
    line: 'AlSiC is a metal-matrix composite, not a single alloy. CPS Technologies describes a two-step process: quickset injection moulding makes a porous ceramic preform that matches the final part geometry, then pressurised melt infiltration fills the preform porosity with aluminium, giving a fully dense part with the same shape (CPS 2025 slide). Wikipedia describes the same route as injection moulding of a silicon carbide binder slurry, firing to remove the binder, then infiltration under pressure with molten aluminium.'
    parts:
      - name: Aluminium alloy 356 (matrix)
        symbol: Al
        share: 37% vol (AlSiC-9) to 63% vol (AlSiC-12)
        role: Metal matrix that is infiltrated into the SiC preform. Wikipedia says the aluminium matrix has many dislocations, which give the material its strength.
      - name: Silicon carbide (reinforcement)
        symbol: SiC
        share: 63% vol (AlSiC-9) to 37% vol (AlSiC-12)
        role: Particle reinforcement that sets the thermal expansion.
  why: AlSiC is used where a part must match the thermal expansion of a chip and still carry heat away while staying light. CPS Technologies prints a thermal conductivity of 190 W/mK typical at 25 °C for AlSiC-9, with a minimum of 180 W/mK, and a coefficient of thermal expansion of 8.00 ppm/°C from 30 to 100 °C. Wikipedia says the thermal expansion can be tuned to match silicon, gallium arsenide and several ceramics, and that AlSiC is mainly used in microelectronics as a substrate for power semiconductors.
  can_do:
    - label: Carry heat
      value: 190 W/mK typical, AlSiC-9, 25 °C
      benchmark: thermal_conductivity
      line: CPS Technologies prints 190 W/mK typical and 180 W/mK minimum at 25 °C for AlSiC-9, and 180 W/mK typical and 170 W/mK minimum for AlSiC-12. Wikipedia gives 190-200 W/m K for AlSiC-9 and AlSiC-10, and 170-180 W/m K for AlSiC-12, without a temperature.
    - label: Match a chip's expansion
      value: 8.00 ppm/°C, AlSiC-9, 30-100 °C
      benchmark: cte
      line: CPS prints 8.00 ppm/°C from 30 to 100 °C and 8.75 ppm/°C from 30 to 200 °C for AlSiC-9. The same slide prints 10.90 ppm/°C and 11.70 ppm/°C for AlSiC-12 over the same ranges.
    - label: Stay light
      value: 2.89 to 3.01 g/cm3
      benchmark: density
      line: CPS prints 3.01 g/cm3 for AlSiC-9 and 2.89 g/cm3 for AlSiC-12. CPS's hermetic packaging datasheet says AlSiC is 40-60% lighter than CuMo and CuW.
    - label: Form complex parts
      value: Near net shape
      line: Ferrotec lists near net shape processing as a benefit, and CPS says net-shape manufacturing removes costly machining. The sources do not give a tolerance.
  compare: 'CuMo and CuW are the heat-spreader alternatives AlSiC replaces. CPS''s hermetic packaging datasheet says AlSiC is 40-60% lighter than CuMo and CuW and lower in cost. Wikipedia says AlSiC weighs about one-third as much as copper. Inside the family, the Ferrotec table shows the trade-off: going from Al75/SiC25 to Al60/SiC40 lowers the printed coefficient of thermal expansion from 15 to 13 (1/°C×10-6) and raises the printed density from 2.8 to 2.9 g/cm3. The sources give no like-for-like figure against a bare aluminium alloy, so none is stated here.'
  compare_rows:
    - label: Density
      benchmark: density
    - label: Thermal conductivity
      benchmark: thermal_conductivity
    - label: Thermal expansion
      benchmark: cte
  handling:
    - 'Name the grade on every drawing: AlSiC-9, AlSiC-10 and AlSiC-12 differ in thermal expansion, conductivity and density.'
    - Control silicon carbide dust when cutting, grinding or drilling. The IARC concern is fibrous silicon carbide, and PubChem quotes NIOSH for eye, skin and airway irritation.
    - Plating is possible. Wikipedia says nickel or nickel-gold plating and thermal spray coatings are used, but the sources read give no corrosion data for those finishes.
  good_for:
    - 'Matching a chip''s expansion while removing heat: AlSiC-9 has 8.00 ppm/°C from 30 to 100 °C and 190 W/mK typical at 25 °C (CPS 2025).'
    - 'Light heat spreaders and coolers: 3.01 g/cm3 for AlSiC-9, and a single-piece cooler with integrated channels (CPS 2025).'
    - 'Hermetic housings: CPS says its hermetic packages use a two-step sealing process (CPS hermetic packaging datasheet).'
  watch_out:
    - 'Brittle at the limit: AlSiC-9 prints 11.3 MPa/m2 fracture toughness and 0.295 percent elongation at rupture (CPS 2025).'
    - 'Grade choice changes the match: AlSiC-9 is 8.75 ppm/°C and AlSiC-12 is 11.70 ppm/°C at 30-200 °C (CPS 2025).'
    - 'Silicon carbide dust: PubChem lists H350i for silicon carbide, and quotes IARC Vol. 111 for fibrous silicon carbide (Group 2B) and whiskers (Group 2A).'
    - 'Coating data are thin: Wikipedia says nickel or nickel-gold plating is possible, but the sources read give no corrosion or galvanic test data.'
  verdict: AlSiC is a light, low-expansion metal-matrix composite for power electronics and hermetic packages. The CPS 2025 slide gives the grade-level values, with 190 W/mK typical and 8.00 ppm/°C for AlSiC-9. The space uses are vendor statements from CPS's company history, and no NASA or ESA material-selection document was found in this run. Corrosion data, silicon carbide supply and fracture data for the other grades are gaps.
  risk_groups:
    - title: For people
      lead: The silicon carbide hazard depends on the form of the dust, and the sources differ on how serious it is.
      level: 1
      verdict: Mixed notifications
      points:
        - label: Silicon carbide as a substance
          line: PubChem reports H350i, May cause cancer by inhalation, with signal word Danger. The ECHA aggregation says 740 of 1053 company reports did not meet GHS hazard criteria.
        - label: Fibre versus particle
          line: IARC Vol. 111 lists fibrous silicon carbide as Group 2B and whiskers as Group 2A, while ACGIH says nonfibrous particles have low to very low toxic effects on lung tissue.
        - label: Irritation
          line: The NIOSH Pocket Guide excerpt in PubChem lists irritation of the eyes, skin and upper respiratory system, and cough.
gaps:
  - Corrosion or ageing of AlSiC in air, humidity or salt was not found in the sources read. Wikipedia names nickel and nickel-gold plating, with no test data, and the galvanic points from search results were not opened as sources.
  - Silicon carbide supply and production shares were not found. The USGS aluminium report was read, but no silicon carbide report was opened.
  - The USGS 2026 aluminum text read does not show a critical-minerals listing, so critical_lists is empty for aluminium.
  - Fracture toughness is not in the canonical property list, so it is stored as fracture_toughness with the unit printed by CPS (MPa/m2).
  - CPS prints Electrical Resistance in µOhm-cm for AlSiC. It is stored as electrical_resistivity with that printed unit, and the quantity name may differ from the test method.
  - CPS prints hermeticity as <10-9 atm-cm3/s He. It is not stored, because the canonical list has no helium leak-rate property.
  - Temperatures and test conditions are not printed on the Ferrotec page for its volume-fraction table (density, CTE, thermal conductivity, Young's modulus). Wikipedia gives its thermal conductivity without a temperature.
  - No orbit or radiation environment is set for AlSiC, because the sources name the International Space Station and GPS satellites without stating an orbit for the parts.
  - Space flight use is a vendor statement from the CPS company history. No NASA or ESA material-selection document was found in this run.
  - No peer-reviewed or open-access AlSiC property paper was opened. A squeeze-cast SiCp/Al study and a Rogers HEATWAVE AlSiC-8 datasheet were seen only in search snippets, and their values are not recorded.
  - The density of silicon carbide itself is not stored, because no fetched page printed it.
  - No machining or dust-control guidance from a supplier was found. The handling points come from the IARC, ACGIH and NIOSH text quoted by PubChem.
  - Ferrotec prints its CTE unit as 1/°C×10-6. It is stored as ppm/°C with the printed unit kept in conditions.
documents:
  - title: 'Wikipedia: AlSiC'
    type: database
    url: https://en.wikipedia.org/wiki/AlSiC
  - title: Al-SiC Metal Matrix Composite Ceramic Material (Ferrotec Advanced Ceramics)
    type: datasheet
    url: https://ceramics.ferrotec.com/materials/metal-matrix/al-sic/
  - title: CPS AlSiC Composites, 2025 product slide
    type: datasheet
    url: https://cpstechnologysolutions.com/wp-content/uploads/2025/09/CPS-Alsic-2025-Final.pdf
    year: 2025
  - title: CPS AlSiC Hermetic Packaging datasheet
    type: datasheet
    url: https://cpstechnologysolutions.com/wp-content/uploads/2025/01/AlSiC-HP-Data-Sheet.pdf
  - title: 'Mineral Commodity Summaries 2026: Aluminum (U.S. Geological Survey)'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
  - title: 'PubChem: Silicon carbide, CID 9863'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/Silicon-carbide
  - title: AlSiC Pin Fin Coolers, CPS Technologies product sheet
    type: datasheet
    url: https://cpstechnologysolutions.com/wp-content/uploads/2022/03/CPS-Automotive_PinFins-Reformatted.pdf
sources:
  wikipedia-alsic:
    title: AlSiC
    url: https://en.wikipedia.org/wiki/AlSiC
    kind: web
    license: CC BY-SA 4.0 (cited, not reproduced)
  ferrotec-alsic:
    title: Al-SiC Metal Matrix Composite Ceramic Material (Ferrotec Advanced Ceramics)
    url: https://ceramics.ferrotec.com/materials/metal-matrix/al-sic/
    kind: web
  cps-alsic-2025:
    title: CPS AlSiC Composites, 2025 product slide (Select Material Properties)
    url: https://cpstechnologysolutions.com/wp-content/uploads/2025/09/CPS-Alsic-2025-Final.pdf
    year: 2025
    kind: datasheet
  cps-hp-datasheet:
    title: AlSiC Hermetic Packaging datasheet, CPS Technologies
    url: https://cpstechnologysolutions.com/wp-content/uploads/2025/01/AlSiC-HP-Data-Sheet.pdf
    kind: datasheet
  cps-history:
    title: Our History, CPS Technologies (company web page)
    url: https://cpstechnologysolutions.com/our-history/
    kind: web
  cps-pinfin:
    title: AlSiC Pin Fin Coolers, CPS Technologies product sheet
    url: https://cpstechnologysolutions.com/wp-content/uploads/2022/03/CPS-Automotive_PinFins-Reformatted.pdf
    kind: datasheet
  usgs-mcs2026-aluminum:
    title: 'Mineral Commodity Summaries 2026: Aluminum'
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
    kind: report
  pubchem-sic:
    title: PubChem, Silicon carbide, CID 9863
    url: https://pubchem.ncbi.nlm.nih.gov/compound/Silicon-carbide
    kind: database
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 33
  caveats: 5
  note: 'Draft profile written to the brief''s depth. Corrosion and silicon carbide supply are open gaps, and the CPS electrical resistance and fracture toughness names are not canonical. Caveats: Values were read by an AI assistant on 2026-11-01 from the pages and PDFs named in each entry (CPS slides and datasheet extracted from the PDF text; USGS aluminum text extracted from the PDF). Grade values from CPS and Ferrotec are manufacturer figures, and the grade-to-column mapping was read from the printed table. The Ferrotec and Wikipedia figures give no test temperature for most values, and are kept as printed. Space use is a vendor statement from CPS''s company history; no NASA or ESA document was read. No corrosion, supply of silicon carbide, or peer-reviewed property paper was recorded.'