Aluminum is the most common material we machine, and the two grades we see most often are 6061-T6 and 7075-T6. They look similar, but their mechanical properties and costs differ significantly.
## 6061-T6: The General-Purpose Workhorse
– **Strength**: Ultimate tensile strength ~310 MPa
– **Machinability**: Good — produces clean chips, easy to surface finish
– **Weldability**: Excellent
– **Cost**: Lower — widely available, less expensive
– **Best for**: Housings, brackets, fixtures, enclosures, structural parts
6061 is the default choice for most CNC aluminum parts. It machines predictably, anodizes well, and is readily available in bar and plate form.
## 7075-T6: The High-Strength Aerospace Alloy
– **Strength**: Ultimate tensile strength ~570 MPa (nearly double 6061)
– **Machinability**: Good — but harder on tooling
– **Weldability**: Poor — not recommended for welded assemblies
– **Cost**: Higher — 2-3x the price of 6061
– **Best for**: Aerospace components, high-stress structural parts, weapon components, bicycle frames
7075 is when you need maximum strength at minimum weight. It’s commonly used in aerospace, defense, and high-performance robotics.
## Our Recommendation
If your part is non-critical or you’re prototyping, start with 6061. If weight reduction and strength are paramount, 7075 is worth the premium.
We machine both alloys daily, and can help you select the right material based on your application and budget. Request a quote with your drawing, and we’ll recommend the optimal grade.