以进口生产ER5356铝合金焊丝用连铸连轧杆原料为研究对象，采用高温拉伸试验研究了不同温度（250~550 ℃）下连铸连轧杆的高温强度、塑性变化规律，并观察了断口形貌，得到最佳热塑性温度区间。结果表明：随着温度升高，该连铸连轧杆的高温强度呈单指数降低趋势，断后伸长率增大，断面收缩率变化不大，说明该连铸连轧杆具有较好的高温塑性；随着温度升高，晶界弱化，沿晶断裂区域面积增加，拉伸断口形貌由韧窝变为韧窝+脆性沿晶断裂混合形貌，最后完全变为脆性沿晶断裂形貌；ER5356铝合金连铸连轧杆的最佳热塑性温度区间为375~525 ℃。

Taking the imported continuous casting and rolling rod raw materials for production of ER5356 aluminum alloy welding wire as the research object, the high temperature strength and plastic change of the continuous casting and rolling rod at different temperatures (250-550 ℃) were studied by high temperature tensile tests, and the fracture morphology was observed. The best thermoplastic temperature range was obtained. The results show that with increasing temperature, the high temperature strength of the continuous casting and rolling rod showed a single exponential decrease trend, the percentage elongation after fracture increased, and the percentage reduction of area changed little, indicating the continuous casting and rolling rod had good high temperature plasticity. With increasing temperature, the grain boundary weakened, and the area of the intergranular fracture area increased; the tensile fracture morphology changed from dimples to dimples and brittle intergranular fracture mixed morphology, and finally completely changed to the brittle intergranular fracture morphology. The best thermoplastic temperature range of ER5356 aluminum alloy continuous casting and rolling rod was 375-525 ℃.