Laser surface cladding of ZM5 Mg-base alloy with
Al+Y powder
Al+Y powder
(State Key Laboratory for Corrosion and Protection, Institute of Metal Research,
Chinese Academy of Sciences, Shenyang 110016, China)
Chinese Academy of Sciences, Shenyang 110016, China)
Abstract: The surface properties of ZM5 Mg-base alloy were modified by laser cladding with Al+Y powder. Laser cladding was carried out with a 5kW continuous wave CO2 laser by melting the preplaced powder mixture of Al and Y. Following laser cladding, the cladding zone was characterized by a detailed microstructural observation and phase analysis. Moreover, the microhardness and element distribution were evaluated in detail. The surface modified layer consists of Mg17Al12 and Al4MgY phases, while α-Mg and Mg17Al12 in the substrate. The microhardness of the cladding zone was significantly enhanced as high as HV122-180 as compared to HV60-80 of the substrate region. The maximal hardness about HV224 is in the interface due to the formation of intermetallic Mg17Al12 phase. The microstructure is refined and Mg diffuses into the cladding material which leads to the formation of Mg17Al12.
Key words: laser cladding; ZM5 Mg base alloy; rare earth; Al+Y powder; microstructure