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AZ91/SiC/15p SC

Finish state

SC = squeeze cast / pressure infiltrated

Pick when porosity must be minimised and particle distribution uniform for fatigue-loaded parts.

High cost $$$$

Values for the SC condition

Other AZ91/SiC/15p grades and fills

AZ91/SiC/15p is listed in 4 conditions; see the grade overview at AZ91/SiC/15p.

Compare all 4 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Solution heat treated and naturally aged
Choose when the best available ductility and impact tolerance is needed from the composite.1202302.5—
FDefault
As fabricated
Baseline stir-cast condition: cheapest route, use where stiffness and wear matter more than strength.1302001.2—
SCThis page
Squeeze cast / pressure infiltrated
Pick when porosity must be minimised and particle distribution uniform for fatigue-loaded parts.1552402—
Solution heat treated and artificially aged
Highest hardness/yield and best wear performance; accept the loss of ductility.1752501—

What is AZ91/SiC/15p SC?

AZ91/SiC/15p SC is AZ91/SiC/15p supplied in the SC condition — pick when porosity must be minimised and particle distribution uniform for fatigue-loaded parts. AZ91/SiC/15p SC has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 63% of composite grades. Elongation at break is 2% and the elastic modulus is 59 GPa (8.56 Msi). AZ91/SiC/15p SC has a density of 2.02 g/cm³ (0.073 lb/in³), heavier than 78% of composite grades. F is the default condition FabDigit quotes; SC is available on request or by drawing note.

Advantages

  • Conducts heat well — 78 W/m·K (45.1 BTU/hr·ft·°F), better than 88% of composite grades

Limitations

  • Needs corrosion protection — 17/100, worse than 99% of composite grades
  • High embodied carbon — 30 kg CO₂/kg, worse than 80% of composite grades
  • Heavy — 2.02 g/cm³ (0.073 lb/in³), worse than 78% of composite grades

AZ91/SiC/15p SC properties

Typical room-temperature values for AZ91/SiC/15p SC; 14 are specific to this condition. Other listed values are AZ91/SiC/15p reference data and may not represent this condition. Bars are the position among composite grades.

Physical1

AZ91/SiC/15p SC has a density of 2.02 g/cm³ (0.073 lb/in³), heavier than 78% of composite grades.

Density2.02 g/cm³0.07 lb/in³

Mechanical13

AZ91/SiC/15p SC has a yield strength of 155 MPa (22.5 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 63% of composite grades. Elongation at break is 2% and the elastic modulus is 59 GPa (8.56 Msi).

Elastic (Young's) Modulus59 GPa8.6 Msi
Shear Modulus21.8 GPa3.2 Msi
Bulk Modulus50 GPa7.3 Msi
Poisson's Ratio0.31
Tensile Strength (Ultimate)240 MPa34.8 ksi
Yield Strength (0.2% offset)155 MPa22.5 ksi
Elongation at Break2%
Compressive Strength430 MPa62.4 ksi
Compressive Modulus57 GPa8.3 Msi
Flexural Strength390 MPa56.6 ksi
Flexural Modulus58 GPa8.4 Msi
Shear Strength165 MPa23.9 ksi
Fracture Toughness (K_IC)13 MPa·√m11.8 ksi·√in

Thermal6

AZ91/SiC/15p SC is rated for continuous service to 150°C (302 °F). It conducts heat at 78 W/m·K (45.1 BTU/hr·ft·°F), better than 88% of composite grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).

Thermal Conductivity78 W/m·K45.1 BTU/hr·ft·°F
Specific Heat Capacity970 J/kg·K0.23 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)21.5 µm/m·K11.9 µin/in·°F
Max Service Temperature (continuous)150°C302 °F
Min Service Temperature-50°C-58 °F
Max Service Temperature (short-term)200°C392 °F

Electrical1

AZ91/SiC/15p SC has an electrical resistivity of 1.75×10⁻⁷ Ω·m.

Electrical Resistivity1.75×10⁻⁷ Ω·m6.89 µΩ·in

Chemical & Environmental3

Corrosion resistance is poor (17/100), worse than 99% of composite grades. UV resistance is fair.

Corrosion ResistancePoor17/100
UV / Weathering ResistanceFair45/100
Chemical Resistance SummaryAttacked by water, salt solutions and acids; galvanic corrosion at SiC/Mg interfaces accelerates pitting. Stable in dry air, most alcohols, hydrocarbons, alkalis and fluorides. Requires chemical conversion coating, anodizing (e.g. Keronite/MAO) plus sealing or paint for any humid or marine service; avoid direct contact with steel, brass or carbon fibre parts.

Sustainability4

Producing a kilogram of AZ91/SiC/15p SC takes about 300 MJ of energy and emits 30 kg of CO₂ — more than 68% of composite grades. Typical recycled content is 5%.

Embodied Energy (primary production)300 MJ/kg128,977 BTU/lb
Embodied Carbon (primary production)30 kg CO₂/kg
Embodied Water500 L/kg59.9 gal/lb
Typical Recycled Content5%

Manufacturability2

AZ91/SiC/15p SC's machinability is fair (42/100, better than 58% of composite grades).

MachinabilityFair42/100
PolishabilityFair45/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with AZ91/SiC/15p SC

Is AZ91/SiC/15p easy to machine?

Highly abrasive: use PCD or diamond-coated tooling, high speed / light feed, flood or MQL coolant, and treat all Mg chips and fines as a fire hazard (never water-quench).

Can AZ91/SiC/15p be welded?

Fusion welding is generally not recommended — SiC reacts with molten Mg and porosity is severe; join by mechanical fastening, adhesive bonding or friction-stir welding with careful parameter control.

Can AZ91/SiC/15p be formed, bent or molded?

Produced by stir/compo casting or squeeze casting with degassed melt and SF6-free cover gas; cold forming is impractical, hot extrusion at 300-400 °C is possible for billet-to-bar conversion.

What surface finishes work on AZ91/SiC/15p?

Requires conversion coating or plasma-electrolytic (MAO) anodizing plus a sealer or paint; SiC particles resist the anodic film locally, so coating continuity must be inspected, and direct contact with steel or CFRP must be electrically isolated.

AZ91/SiC/15p chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
SiCreinforcement: 15 vol% particulate (typ. 10-20 µm) = ~24 wt%; balance below refers to the AZ91 matrix20 – 2723.8
Almatrix basis, ASTM B93 AZ918.3 – 9.79
Znmatrix basis0.35 – 10.7
Mnmatrix basis0.15 – 0.50.25
Simatrix impurity limit; excludes SiC reinforcement≤ 0.1—
Cumatrix impurity limit≤ 0.03—
Nimatrix impurity limit, critical for corrosion≤ 0—
Fematrix impurity limit, critical for corrosion≤ 0.01—
Mgmatrix balancebalance—

AZ91/SiC/15p SC — frequently asked

What is AZ91/SiC/15p SC used for?

AZ91/SiC/15p SC is typically used for automotive lightweight brackets, electronic housings and aerospace lightweight castings. In short: lightest structural MMC; stiffer than cast magnesium; very low ductility.

What is the yield strength of AZ91/SiC/15p SC?

AZ91/SiC/15p SC has a typical yield strength of 155 MPa (22.5 ksi) and a tensile strength of 240 MPa (34.8 ksi) — weaker than 63% of composite grades. Strength varies by condition: see the 4 listed tempers.

Is AZ91/SiC/15p SC easy to machine?

Not especially — machinability is rated fair (42/100, better than 58% of composite grades). Highly abrasive: use PCD or diamond-coated tooling, high speed / light feed, flood or MQL coolant, and treat all Mg chips and fines as a fire hazard (never water-quench).

Can AZ91/SiC/15p SC be welded?

Fusion welding is generally not recommended — SiC reacts with molten Mg and porosity is severe; join by mechanical fastening, adhesive bonding or friction-stir welding with careful parameter control.

What surface finishes work on AZ91/SiC/15p SC?

Requires conversion coating or plasma-electrolytic (MAO) anodizing plus a sealer or paint; SiC particles resist the anodic film locally, so coating continuity must be inspected, and direct contact with steel or CFRP must be electrically isolated.

Can AZ91/SiC/15p SC be formed, bent or molded?

Produced by stir/compo casting or squeeze casting with degassed melt and SF6-free cover gas; cold forming is impractical, hot extrusion at 300-400 °C is possible for billet-to-bar conversion.

What is the maximum service temperature of AZ91/SiC/15p SC?

AZ91/SiC/15p SC is rated for continuous use to about 150°C (302 °F), and briefly to 200°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between AZ91/SiC/15p F and AZ91/SiC/15p T6?

F is the default condition — baseline stir-cast condition: cheapest route, use where stiffness and wear matter more than strength. T6: highest hardness/yield and best wear performance; accept the loss of ductility. Yield strength is 130 MPa in F versus 175 MPa in T6.

Sources

  1. ASM Handbook Vol. 21: Composites — Discontinuously Reinforced Metal-Matrix Composites — ASM International (2001)
  2. ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys (AZ91 magnesium) — ASM International (1990)
  3. ASTM B93/B93M — Magnesium Alloys in Ingot Form for Sand, Permanent Mold and Die Castings — ASTM International (2020)
  4. MMC property compilations (stir-cast AZ91/SiCp studies) — open composites literature (2020)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.