Gary Sharp

New generations of advanced high-strength steels (AHSS) used in the auto industry create great challenges for stamping tools used in those applications because the stress required to induce sufficient plastic deformation in steel with tensile strengths as high as 1,800 MPa is as much as 400 megapascals. Chromium plating has been used successfully to protect stamping dies for many years. However, chromium plating’s limitations seem to be more pronounced as AHSS become harder. In recent years a technique called ion/plasma nitriding has been successful in surface hardening of those tools and dies. This is especially true when the cast materials are alloyed with chromium, molybdenum, and other elements, which form very stable and hard nitrides.