Gas or plasma processing of high-chrome steel workpiece surfaces - involves forming connecting layer with improved corrosion w.r.t. graphite and wear resistance for treating e.g valve spindles

摘要

Workpieces in high-chrome steel, e.g. valve spindles from power station valves, undergo treatment in gas or plasma to form a connecting layer on their surface. Connecting layer is pref. composed mainly of nitrides, together with C, S, P and/or other nonmetals. ADVANTAGE - Corrosion resistance w.r.t. graphite, wear resistance and temp. resistance are improved