Microstructure and performance of laser cladding on surface of aluminum bronze

A Ni matrix alloy cladding was deposited on the surface of QAl9-4 aluminum bronze by laser remelted technology to improve its wear resistance. In order to improve absorptivity of aluminum bronze for laser irradiation, some alloy powders were pre-deposited on the surface of QAl9-4 aluminum bronze by compressive equipment and some binder, which was developed by researcher. Then, these alloy powders were remelted by laser. The analysis of the laser cladding on the surface of QAl9-4 aluminum bronze shows that the composite region of remelted cladding and QAl9-4 aluminum bronze is a better metallurgical bond and there aren't cracks. The microstructure of cladding is affected by solidification rate. The microstructure of the cladding's surface is cellulated crystal. In the middle part of the cladding, the microstructure is dendritic crystal. Because of chilling effect of QAl9-4 aluminum bronze, the microstructure of the composite region upper is fine grain band. The microstructure of the composite region lower is cellulated crystal and dendritic crystal. The average Vickers hardness of the cladding is three times as hard as that of ordinary QAl9-4 aluminum bronze.