Abstract: In a method of increasing the wear resistance and the corrosion resistance f opposed bearing surfaces of parts subjected to reciprocal friction, in particular when the product of the pressure distributed over the bearing surfaces by the relative speed of the latter exceeds 0.4 MPa.m/s, thermochemical diffusion of nitrogen is effected by nitriding or nitrocarburizing in a molten salt bath at a temperature of 570.degree. C..+-.15.degree. C. followed by an oxidizing or phosphating surface chemical reaction providing resistance to wet corrosion. The nitriding or nitrocarburizing molten salt bath is made up of alkaline carbonates and cyanates and further contains sulfur-containing substances in the following percentages by weight:30%<CNO.sup.- <45%15%<CO.sub.3.sup.2- <25%15%<Na.sup.+ <25%20%<K.sup.+ <30%1%<Li.sup.+ <6%1 ppm<S.sup.2- <100 ppmThe time for which parts are immersed in the bath is between 15 minutes and 45 minutes.

Abstract: A bearing shell for heavily loaded bearings with a rolled strip interfere or force fit lining comprises a generally annular body with an axial bore fitted with a lining in which a shaft turns. The lining comprises a 2 mm thick rectangle of rolled steel strip at least the bearing surface of which has been surface hardened to a depth of approximately 0.5 mm by nitriding or by carburizing and quenching. The ends of the rolled strip bear on each other. The strip is an interference or force fit in the bore of the body and has an excess length relative to the developed length of a neutral fiber of an unstressed lining between 0.3 and 9%.