Role of preheating and specific energy input on the evolution of microstructure and wear properties of laser clad Fe-Cr-C-W alloys

Synthesis of Fe-Cr-C-W alloy (10 : 4 : 1 : 1, wt(%)) was carried out on AIS I 1016 steel substrate using laser cladding technique which lead to the dev elopment of a suitable alternate for cobalt bearing wear resistant alloys. This study involved understanding of process variables like preheating temp erature and specific energy input on the evolution of microstructures and t heir effect on wear resistance properties. The microstructure was examined with a scanning electron microscope and various types of complex carbides w ere identified using both energy dispersive x-ray and auger spectroscopy fa cilities. A combination of MC, M7C3 and M6C types of carbides of certain pr oportions (formed at a preheating temperature of 484 degrees C with specifi c energy input of 9.447 KJ/cm(2)) has been found to be most attractive for achieving an optimum combination of microhardness and steady state friction coefficient values. A similar advantage may be derived at a lower level of specific energy input of 8.995 KJ/cm(2) but with a higher preheating tempe rature of 694 degrees C. However, increasing the specific energy input to 1 2.376 KJ/cm(2) can significantly soften the matrix. (C) 2000 Kluwer Academi c Publishers.