The IC10 single crystal superalloys are welded by the laser welding process,and the effects of welding speed on joint weld forming,cross-section morphology and microstructure are analyzed.The results show that the surface and back widths of welds increase with the decrease of welding speed.The cross-sections of welds under different welding speeds all show a typical goblet shape.The welds mainly consist of fine grains,cellular crystals and columnar crystals.The welding cracks extending along the grain bound...