It depends entirely on the application — they serve different purposes.
6061 Aluminum
- Medium strength, good corrosion resistance, excellent weldability and machinability
- T6 tensile strength: 310 MPa / 276 MPa yield
- Cost-effective, versatile
- Best for structural frames, brackets, tubes, machining parts
7075 Aluminum
- Ultra-high strength (572 MPa tensile, T6), top-tier aluminum alloy
- Poor corrosion resistance, not weldable
- Used in aerospace, high-stress components, aircraft parts
Summary: For general engineering, machining, welding, cost: 6061 is better; For maximum strength, aerospace, high load: 7075 is better. Neither is designed for casting.

An aluminum casting alloy is a specially formulated aluminum-based material optimized for molten casting processes. Key characteristics include:
- High silicon content (typically 5–13%) to improve melt fluidity
- Low shrinkage and reduced porosity
- Good mold-filling ability
- Stable casting performance at 660–720°C
- Balanced strength, ductility, and machinability
Common standard casting alloys: ADC10, ADC12, A356, A357, A380, AlSi9Cu3, AlSi12. These are completely different from wrought alloys like 6061 and 7075.

Aluminum alloys can be both cast and forged, depending on the alloy grade and manufacturing process.
- Cast aluminum alloys: Designed for casting processes; high silicon content for fluidity; examples: ADC12, A356, A380. Advantages: complex shapes, low tooling cost, mass production.
- Wrought aluminum alloys: Used for forging, extrusion, rolling; examples: 6061, 7075, 5052, 6063. Forged aluminum has higher density, better fatigue resistance, and tighter tolerances.
In short: Casting = shape complexity & cost efficiency; Forging = higher strength & structural integrity.

7075 aluminum is a high-strength wrought alloy (Al-Zn-Mg-Cu) and is NOT a casting alloy. It cannot be effectively cast due to: high hot-cracking tendency, extremely low casting fluidity, and severe internal porosity and segregation. Casting 7075 leads to unusable parts with defect rates >50% and unpredictable mechanical performance. When people refer to “7075 cast,” it usually refers to a misunderstanding or mislabeling. Genuine 7075 is only produced by rolling, extrusion, or forging —never casting.

There is no single “best” alloy — selection depends on application, strength, heat treatment, and cost. The most popular and versatile casting aluminum alloys include:- ADC12: Most common for die casting; good fluidity and castability; tensile strength ~200 MPa; widely used in housings, brackets, automotive parts.
- A356 / A357: Best for heat-treatable, high-strength parts; excellent ductility and pressure tightness; widely used for wheels, pump bodies, structural components; T6 treatment achieves tensile strength up to280–320 MPa.
- A380: High strength, good pressure tightness; ideal for hydraulic parts, engine components; tensile strength ~240 MPa.
- AlSi12: Excellent corrosion resistance and castability; used for thin-walled parts and marine components.
For general mass production, ADC12 is the most cost-effective. For high-performance structural parts, A356 T6 is the industry standard.

Strictly speaking, 6061 aluminum is a wrought alloy, not a casting alloy, so it is not designed or recommended for casting. 6061 has high magnesium and silicon content optimized for extrusion, forging, and machining, but its poor casting fluidity leads to severe porosity, cracks, and shrinkage defects during molten casting. Although technically meltable, casting 6061 results in a defect rate above 30% and unstable mechanical properties. For casting applications, casting-grade alloys such as A356, ADC12, A380, AlSi9Cu3 are always used instead.

Yes, aluminum alloys can be cast and are among the most widely cast non-ferrous metals worldwide. Common casting processes include die casting, gravity casting, sand casting, low-pressure casting, and investment casting. Aluminum casting offers high strength-to-weight ratio, good corrosion resistance, and excellent dimensional stability. Annual global aluminum casting production exceeds 100 million metric tons, covering automotive, electronics, machinery, and aerospace industries.

Yes, we can produce both thick structural components and thin-walled shells by adjusting casting parameters.

We use optimized gating systems, low-speed filling, vacuum-assisted casting, and strict process monitoring to reduce porosity and shrinkage.

Yes, we offer T4, T5, T6 heat treatment to improve strength, hardness, and stability.

Yes, we support prototype, small-batch trial, and mass production for aluminum alloy casting.

General casting tolerance is CT7–CT10; with CNC machining, we can reach IT8–IT10 precision.