Want hardened, corrosion-resistant stainless steel? No problem! Kolsterising® is an industry-proven, surface hardening technology for grades of stainless steel, cobalt and nickel-based alloys. This trusted process provides ultimate hardness and improved mechanical and wear properties - with no loss of corrosion resistance. Kolsterising® is named after the head of the research group that invented the process in the 1980s, Ben H. Kolster (1938-2011).