CHARACTERISTICS OF HYBRID SOLID SOLUTION LAYER FORMED ON THE SURFACE OF 316 L AUSTENITIC STAINLESS STEELS

摘要

Among metallic implant materials, AISI 316L quality austenitic stainless steel is extensively used in manufacturing of orthopedic implants. Although it exhibits very good corrosion resistance in many acidic environments, synergetic attack of corrosion and wear in the body causes severe surface damage and loosening of the implant. It has been reported that surface modification of austenitic stainless steels by forming nitrogen supersaturated surface layer through plasma nitriding provides improvement in both wear and corrosion resistances. In the present study, hybrid nitrogen and carbon supersaturated austenite layer has been formed on the surface of a 316L quality austenitic stainless steel by nitriding in a fluidized bed reactor. After nitriding, the steel exhibited superior surface hardness and wear resistance than as-received state without any significant change in the mechanical properties as well as in vitro bioactivity behavior.