5A06/TC4挤压铸造和半固态锻造连接性能研究

Connection Properties of 5A06/TC4 Joints Prepared by Squeeze Casting and Semi-solid Forging

分别采用挤压铸造和半固态锻造将5A06铝合金与TC4钛合金连接成形,测试分析了接头的剪切强度和界面物相,并通过正交试验获得了最优方案。结果表明,优化后挤压铸造工艺参数:浇注温度为850℃,比压为300 MPa,保压时间为45s,其接头剪切强度平均值为34.55 MPa,800℃时,连接界面生成TiAl_3相,850℃时,生成Ti_3Al相导致剪切强度降低。优化后的半固态锻造工艺参数:铝合金坯料加热温度为625℃,保温时间为60min,比压为300 MPa,其接头剪切强度平均值为57.02 MPa,连接界面主要生成球状Ti基固溶体以及极少量Ti_3Al相,未生成Al_3Ti相,提高了接头剪切强度。

5A06 aluminum alloy and TC4titanium alloy were connected by squeeze casting and semi-solid forging,respectively.The shearing strength and the interface phase of the joint were investigated,and the optimal scheme was obtained by orthogonal experiment.The results show that the optimized process parameters of squeeze casting are presented as follows：poured at 850℃,the applied specific pressure on metal of 300 MPa for 45s,where the average shearing strength of the formed joints reaches 34.55MPa.When the liquid metal is poured at 800℃,the TiAl（3 ）phase can be observed in connection interface,while poured at 850℃,the formation of Ti3Al leads to the decrease of shearing strength.The optimized process parameters for semi-solid thixotropic forging are presented as follows：the heating temperature of the billet at 625℃for 60min,the applied specific pressure on metal of 300MPa,where the average shearing strength of the formed joints reaches 57.02 MPa,and the joint interface can observe spherical Ti-based solid solution and a few Ti3Al and absence of Al3Ti,therefore,the shearing strength of the formed joint is improved.