ELECTRON-BEAM SYNTHESIZED HARD LAYERS ON MILD-STEEL

Hard surfaces have been synthesised on mild steel. The technique involves surface coating followed by electron beam mixing by melting. The coating comprised metallic or metalloid powders, graphite powder and a water soluble binder. Modified surface layers of various dimensions were prepared by controlling electron beam processing parameters. Many carbide forming elements were investigated and boron and tungsten were found to be the most promising. The hardnes of the modified layers depended on the concentration of the alloying elements and varied between similar to 600 and 1000 HV(500 g). The technique is advantageous mainly because hard coatings can be fabricated on almost any substrate that melts under an electron beam. Modified surfaces produced on mild steel are described in the present paper.