IMPROVEMENT OF ROLLING-CONTACT FATIGUE LIFE OF ION-IMPLANTED M50 STEEL

With the overall objective to improve the service life and reliability of gas turbine engine bearings by increasing their corrosion resistan ce and rolling contact fatigue life a collaborative project under the EEC BRITE/EURAM program has been initiated and is now in its third yea r. The aim of the project is to develop an ion implantation technique to implant bearing components with metallic species and to optimise th e process, particularly for applications where salt water contaminatio n of the lubricant may occur. As part of the programme leading up to i mplantation of bearing components, test specimens of M50 bearing steel implanted with Cr+ and Ta+ at several doses have been characterised b y various techniques. This article reports on the implantation work an d the rolling contact fatigue measurements which have been performed i n order to determine the optimum treatment.