铜锡合金不同热挤压温度下的组织分析和性能变化

Microstructure Analysis and Properties Change of Cu-Sn Alloy at Different Hot Extrusion Temperatures

对QSn7-0.2锡青铜先反挤压,然后旋压加工衬套时,由于挤压后的筒形件塑性较差而导致旋压时开裂。为了研究反挤压温度对工件塑性的影响,从而为挤压加工提供最优的温度范围,对QSn7-0.2锡青铜挤压毛坯分别加热至620、640、660、680、700、720℃进行反挤压,采用EBSD技术、SEM对挤压后试件的微观组织和拉伸断口进行了分析,通过拉伸和硬度试验检测了挤压件的力学性能。试验结果表明,700℃挤压得到的试件塑性最好,最有利于后续旋压加工。

When the QSn7-0.2 tin bronze is extrued backward of first and then the bush is formed by spinning,due to the poor plasticity of the extruded cylinder,cracking occurs during spinning.In order to study the effect of back extrusion temperature on workpiece plasticity and provide the optimum temperature range for extrusion processing,the QSn7-0.2 tin bronze extrusion blank was heated to 620,640,660,680,700,720℃respectively and then the backward extrusion was carried out.The microstructure and tensile fracture of extruded specimens were analyzed by EBSD and SEM.The mechanical properties of the extruded parts were tested by tensile and hardness tests.The test results show that the plasticity of the specimens extruded at 700℃is the best,which is most favorable for subsequent spinning.