Comparison of CNC Machining Materials

PEI (polyetherimide) is a high-performance thermoplastic engineering plastic that combines excellent heat resistance, mechanical properties, and chemical stability, enabling it to be widely used in high-end industrial fields such as aerospace, electronics and electrical engineering, and medical equipment.

Polypropylene (PP) is a well-balanced thermoplastic characterized by lightweight material, excellent chemical resistance, and good flexibility. Owing to these properties, it finds wide application in fields such as packaging, household appliances, automotive, daily necessities, and medical devices.

Stainless steel 316 combines exceptional corrosion resistance with excellent machinability. This unique balance of “high corrosion resistance + ease of processing” makes it a material of choice for applications demanding the highest levels of reliability. It is widely employed in fields such as chemical processing, food production, and marine engineering, where it consistently meets stringent performance requirements across diverse operating conditions.

stainless steel 304 is also known as 18/8 stainless steel, which contains approximately 18% chromium (Cr) and 8% nickel (Ni). It not only possesses excellent oxidation resistance and corrosion resistance, but also has good workability and surface quality. Currently, it is the most widely used stainless steel grade in industrial manufacturing and civil applications.

Low carbon steel (with carbon content not exceeding 0.25%) is one of the most commonly used types of steel in both industry and daily life, thanks to its excellent plasticity, weldability, and low cost. It is widely applied in components such as pistons, screws, and drive shafts. However, due to its limited strength, it usually requires post-treatment.

Brass is an alloy primarily composed of copper and zinc. This golden-hued material not only exhibits excellent weather resistance and corrosion resistance, but its tensile strength also rivals that of low-carbon steel, demonstrating outstanding mechanical properties. Brass boasts exceptional machinability, enabling it to support higher feed rates during processing operations such as cutting and stamping, while requiring minimal cutting fluid. This combination significantly reduces both processing costs and process complexity.

As a versatile and widely used metallic material,aluminum 6061 alloy is well-known in the industrial field for its excellent mechanical properties and outstanding weldability. The designations “T6” and “T651,” as typical temper conditions of this alloy, correspond to specific heat treatment processes: the T6 process achieves strength enhancement through solution treatment followed by artificial aging, while the T651 process adds a pre-stretching deformation step on this basis to optimize residual stress distribution. The combined effect of these two processes significantly improves the material’s mechanical properties and effectively eliminates internal stresses. Owing to their comprehensive advantages in strength, processability, and corrosion resistance, 6061-T6 and 6061-T651 aluminum alloys are highly favored in fields such as aerospace structural components, automotive parts, shipbuilding, and general machinery processing, emerging as key foundational materials supporting modern industrial manufacturing.