The effect of thermal cycling by electron-beam surfacing on structure and wear resistance of deposited M2 steel

Structural features of coatings obtained by multiple-pass electron beam cladding of M2 steel powder on steel substrates have been investigated. It is established that a multi-modal size distribution (d1 = 3.8 μm, d2 = 0.65 μm, d3 < 0.25 μm) of reinforcement particles was generated in the carbide subsystem of the clad layer. The volume content of secondary carbides M6C and residual austenite of matrix can be changed in the wide range depending on the thermal cycling induced by incident electron beam. The higher is the content of the retained austenite in the coating, the higher is the wear resistance of the coating due to γ → α′ transformation in cooling and precipitation of secondary carbides in the matrix grains.