9Cr18 steel is a high-carbon, high-chromium martensitic stainless steel known for its high hardness, high wear resistance, and corrosion resistance after quenching. This steel is ideal for manufacturing plastic molds that must endure high wear, heavy loads, and corrosive environments. However, due to the steel’s tendency to form uneven carbide segregation, which can impact the mold’s service life, thermal processing must be strictly controlled, and appropriate processing ratios should be maintained.

Compared to Cr17 steel, 9Cr18 offers improved corrosion resistance while maintaining similar properties. It is primarily used in the manufacture of high-strength, wear-resistant components such as shafts, pumps, valve parts, rods, springs, and fasteners. Special attention should be given to production to prevent the formation of non-uniform carbides, which can affect the quality and performance of the steel.