Why Alloy Selection Matters

Selecting the right aluminum alloy is one of the more important decisions in the casting design process. The alloy you choose affects strength, corrosion resistance, machinability and overall manufacturing cost.

Key Factors to Consider

When selecting an aluminum casting alloy, consider:

  • Mechanical strength
  • Corrosion resistance
  • Machinability
  • Operating environment
  • Cost

Balancing these requirements early in the design process helps optimize both performance and manufacturability.

Common Aluminum Casting Alloys

A356: The Most Versatile Choice

A356 is one of the most widely used aluminum casting alloys due to its excellent balance of strength, corrosion resistance, castability and machinability.

Common Applications:

  • Industrial equipment castings
  • Structural castings
  • Decorative castings
  • Automotive component castings
  • Electrical component castings

319: A Cost-Effective Solution

319 aluminum offers good strength and excellent machinability at a lower material cost, making it a popular choice for low to high volume industrial applications.

Common Applications:

  • Engine components
  • Gear cases
  • Compressor housings
  • Decorative castings

355: Higher Strength for Demanding Applications

When applications require greater mechanical properties, 355 aluminum provides higher tensile and yield strength than A356.

Common Applications:

  • Structural castings
  • Heavy-duty industrial equipment
  • Transportation applications

713: Ideal for Pressure-Tight Castings

713 aluminum is known for its excellent pressure tightness and corrosion resistance, making it a preferred choice for fluid-handling applications.

Common Applications:

  • Pump housings
  • Valve bodies
  • Hydraulic components

535: Superior Corrosion Resistance

For harsh environments, 535 aluminum offers outstanding resistance to corrosion, particularly in marine and outdoor applications.

Common Applications:

  • Marine equipment
  • Outdoor industrial components
  • Transportation equipment

Quick Alloy Comparison

AlloyKey AdvantageTypical Use
A356Balanced performanceGeneral industrial applications
319Cost-effective and machinableEngine and industrial components
355Higher strengthStructural applications
713Pressure tightnessPumps and valves
535Corrosion resistanceMarine and outdoor equipment

Why Early Collaboration Matters

Selecting the right alloy involves more than reviewing material property charts. An experienced casting and machining partner can help evaluate performance requirements, manufacturing considerations, and cost objectives to identify the best solution for your application.

Final Thoughts

The right aluminum alloy can improve product performance, simplify manufacturing and reduce overall costs.

Whether your priority is strength, corrosion resistance, pressure tightness or machinability, understanding the differences between A356, 319, 355, 713, and 535 alloys can help ensure long-term success and cost savings for your casting project.

If you’re developing a new aluminum casting, give us a call at Cast Metals Technology.  We are happy to help you select the most effective alloy for both performance and production goals.