Microstructure of the clad layer of chromium on to mild steel by low-pressure laser spraying

The microstructure of the clad layer of chromium on to a mild steel obtained by low-pressure laser spraying (LPLS) is investigated by cross-sectional electron microscopy (XTEM). When impinged energy density E-i on the substrate is selected to be 64 W mm(-2) the clad layer consists of a Cr30Fe70 alloy with a layer-by-layer structure. The thickness of the first sub-layer is 3-7 mu m. The crystalline orientation of one sub-layer is markedly different from another, but sub-layers smoothly contact each other. One sub-layer is presumably deposited by one pass of laser spraying. (C) 1998 Elsevier Science S.A.