NOUFERROUS METALLURGICAL EQUIPMENT

The effects of annealing temperature (220~380℃) on microstructure, mechanical properties, tensile fracture morphology and phase composition of MgAZ31 and Al (1A99) rolle-bonding layers were studied by scanning electron microscopy (SEM), optical microscopy (OM), tensile testing machine and X-ray diffraction (XRD). The results show that with the increase of annealing temperatures, magnesium and aluminum atoms gradually diffuse and migrate, and the thickness of diffusion layer increases，from 1.80μm at 220℃ to 45.10μm at 380℃, the growth rate of diffusion layer increases gradually.When the annealing temperature reaches 300℃, dense dimples appear at the fracture, and the fracture type of magnesium matrix changes to plastic fracture. The plasticity of the magnesium matrix is enhanced. The phase at the fracture surface is Mg₂Al₃ phase, and the tensile strength reaches a maximum of 272.35MPa, At this time, the comprehensive mechanical properties of the specimen reach the best, therefore,300℃ is the best annealing temperature.