AC8A

AC8A is a high-strength, heat-resistant aluminum alloy ideal for structural die cast parts in automotive, industrial, and powertrain systems.

AC8A aluminum alloy is a high-performance casting material valued for its superior tensile strength, heat resistance, and solid dimensional stability. Classified under JIS H5302, it is widely used in automotive powertrain, industrial machinery, and heat-exposed die-cast components that require mechanical robustness and durability.

At Neway, we offer complete AC8A die casting solutions, integrating mold optimization, post-machining, and surface finishing to deliver high-performance aluminum parts for mission-critical applications.

Key Characteristics of AC8A Aluminum Alloy

Property	Value (Typical, As-Cast)
Density	2.72 g/cm³
Ultimate Tensile Strength	~360 MPa (52,200 psi)
Yield Strength	~210 MPa (30,500 psi)
Elongation at Break	~2.5%
Thermal Conductivity	~105 W/m·K
Coefficient of Thermal Expansion	~21 µm/m·°C
Brinell Hardness	~90 HB
Heat Resistance	Excellent (stable above 250°C)

AC8A exhibits superior mechanical strength and good high-temperature dimensional stability, making it a trusted choice in elevated temperature service or high-load-bearing applications.

Chemical Composition of AC8A

Element	Composition (wt%)
Silicon (Si)	9.0 – 10.0
Copper (Cu)	3.0 – 4.0
Magnesium (Mg)	0.30 – 0.60
Iron (Fe)	≤ 1.3
Manganese (Mn)	≤ 0.50
Zinc (Zn)	≤ 1.0
Nickel (Ni)	≤ 0.50
Aluminum (Al)	Balance

The copper and magnesium content reinforces strength and heat resistance, while high silicon enhances castability and abrasion resistance.

Mechanical Properties of AC8A Aluminum Alloy

All values are typical of as-cast condition per ASTM B85 and JIS test standards:

Property	Value
Ultimate Tensile Strength	~360 MPa (52,200 psi)
Yield Strength (0.2% offset)	~210 MPa (30,500 psi)
Elongation at Break	~2.5%
Fatigue Strength (10⁸ cycles)	~140 MPa (20,300 psi)
Modulus of Elasticity	~71 GPa
Brinell Hardness	~90 HB

These characteristics make AC8A suitable for stress-bearing components exposed to frequent thermal cycling and structural vibrations.

Benefits of Using AC8A in Die Casting

High Mechanical Strength: Delivers enhanced structural rigidity and load capacity.
Thermal Stability: Maintains form and tolerances at continuous operating temperatures above 200°C.
Good Wear Resistance: Ideal for sliding parts or housings in contact with moving components.
Excellent Castability: Supports high-pressure die casting of thin-walled complex parts.
CNC-Friendly: Stable microstructure reduces tool wear and ensures precision machining.

Typical Applications of AC8A Die Cast Parts

AC8A is widely used in medium-to-heavy-duty components where structural integrity and thermal durability are essential:

Automotive: Cylinder heads, transmission casings, clutch housings, EGR valves
Industrial Machinery: Gearbox covers, hydraulic system components
Motorcycle/ATV Parts: Engine side covers, chain housings
Power Electronics: Thermal shields, high-temp enclosures
Agricultural Equipment: Engine protection covers, control housings

Its superior tensile strength allows design engineers to reduce wall thickness without sacrificing performance.

CNC Machining Considerations for AC8A

Although harder than A380 and A360, AC8A machines well with appropriate tooling strategies.

Machining Recommendations:

Tooling: Use TiAlN-coated carbide or PCD tooling to handle abrasive silicon and copper
Cutting Speed: 150–400 m/min; drilling: 80–120 m/min
Feed Rate: 0.05–0.15 mm/rev
Coolant Use: Required to control heat and chip buildup
Finish Capability: Surface roughness Ra ≤ 1.6 µm achievable with multi-pass finishing
Tolerance Capability: ±0.03 mm on functional features with optimized setup

Neway’s machining systems ensure dimensional repeatability and functional integrity of all AC8A components.

Surface Treatments for AC8A Parts

To enhance wear resistance and appearance, AC8A parts can undergo the following treatments:

Powder Coating: Enhances surface protection for high-heat or outdoor components
Anodizing: Compatible, but copper content may result in darker finishes
Painting: UV- and solvent-resistant coatings for industrial branding
Tumbling: Improves part consistency before coating or assembly

All surface treatments are tested per ISO 2409 (adhesion) and ASTM B117 (salt spray) to ensure performance under operational stress.

Why Choose Neway for AC8A Die Casting?

With end-to-end aluminum die casting capabilities, engineering consultation, and certified mass production systems, Neway delivers high-strength AC8A components tailored to customer specifications. From DFM support to real-time inspection, we ensure every part performs under pressure.