Abstract: Volume fractions of austenite and cementite in laser clad layers are adjusted through adjusting the mass fraction of Si to avoid the formation of cracks. Based on optimum parameters of laser processing to prevent cracks, effects of Si on the volume fractions of austenite, and on the ratio of surface cracking in laser clad layers are systematically investigated for the first time under the condition of no preheating. Cracking mechanisms is analysed. At last new cladding materials that can restrain cracking of laser clad layer is obtained.

Key words: Austenite Grey iron, Crack Si element, Laser clad layer