Material Selection for CNC Parts
Material choice affects raw stock price, machining speed, tool wear, surface finish, inspection, and post-processing. Choosing the cheapest material per kilogram does not always produce the cheapest finished part.
Common economical choices
Aluminum 6061 is popular because it machines quickly, is widely available, and accepts finishes such as anodizing. Mild steels can be economical for strong parts, but may require corrosion protection.
Premium materials
Stainless steel, titanium, Inconel, and engineering plastics may require slower feeds, sharper tooling, coolant control, or special handling. These factors increase cost even when part geometry is simple.
Design fit
Select material based on load, temperature, corrosion, weight, electrical needs, and finishing. If a lower-cost substitute meets the functional requirement, it can reduce both material and machining cost.