The Study Of Mg-al Heterogeneous Alloys Solid-phase Connecting And Its Device

With the rapid development of science and technology in equipment manufacturing field,magnesium and its alloys are known as the most promising metal materials. Hence, it is veryimportant to study and applicatation of the magnesium and aluminum heterogeneous alloyconnection. In order to investigate the law of function between Mg and Al, study the formationand increase process of the intermetallic, improve the structure performance of Mg-Alheterogeneous alloy connection joint and improve the practicability of Mg-Al heterogeneousalloy connection, it is very significant to study on microstructure of Mg-Al heterogeneous alloysolid connection interface zone.The Mg and Al are connected under the different temperature, stress and time parametersby using the existing connection device. The better temperature, pressure and time parametersand the ultimate temperature and pressure parameters of the Mg-Al heterogeneous alloy solidconnection are analysed. The phase composition and microhardness of the joints are alsoanalysed. According to the parameters that obtained by the existing connection device, a highdegree of automation, reasonable structure, low cost and suitable novel Mg-Al heterogeneousalloy solid connection device is designed.By using the existing connection device, the ultimate temperature, stress parameters of12mm×12mm×5mm AZ31B and aluminum board solid connection are500℃and1000N,respectively. The better temperature, stress and time parameters are440℃,800N and90min.Under the condition of440℃,800N and90min, the solid connection joint of Mg-Alheterogeneous alloy is composed of two unsteady diffusion layer which are closing to thematrix and a intermediate diffusion layer. The intermetallic compound of Mg17Al12and Mg3Al2are created in the joint diffusion layer. The microhardness of the joint are range from HV280toHV350.According to the experiment results, the maximum temperature and pressure of the novelMg-Al heterogeneous alloy solid connection device are set as550℃and1000N, respectively..The furnace body, support structure, applied structure and control system of the Mg-Alheterogeneous alloy solid connection device are designed by using these parameters. Theautomatic control and the closed loop control are applied by using the PLC.