高温合金薄壁圆筒焊接变形控制研究

为解决某型号航空发动机产品焊接加工难题,进行了Inconel 718高温合金薄壁圆筒零件焊接变形控制工艺研究。通过分析薄壁筒体焊接变形的原因,采取合理的接头设计、焊接工装设计、优化焊接工艺和焊后热处理及热处理防变形工装等措施,产品焊缝质量满足I级要求,焊缝圆度变形控制在0.2 mm以内。最终通过了验证,较好地控制了高温合金薄壁圆筒产品焊接变形,焊缝质量优良,可为相关薄壁圆筒产品焊接提供技术支持。

ABS塑料与Q235钢异种接头电阻点焊工艺与力学性能的研究

采用电阻点焊实现了ABS塑料与Q235钢异种材料的搭接连接,分析了工艺参数改变对接头成形与力学性能的影响及接头失效后的断口形貌。结果表明,随着焊接电流和焊接时间的增加,接头焊合面积逐渐增大,接头拉伸载荷也随之增大;电极压力改变时,接头拉伸载荷并未出现较大的变化趋势。热输入过大时接头成形质量变差,在搭接界面塑料被大量挤出;在接头界面塑料金属相互嵌合包覆形成了机械互锁结构。接头失效有界面撕裂和塑料母材拉断两种形式。

Study of joining mechanism of ABS polymer and steel/aluminum by resistance spot welding

The joining of metal and polymer is an increasingly important method to get lightweight components in the development of manufacturing industry- nowadays. In this artiele, metal and polymer lap joint was achieved by means of resistance spot welding （RSW） and ultrasonic assistance welding （UAW）. The joining mechanism of lap joint was analyzed by OM, TEM on microstructure at the interface of lap joints and XPS and IR spectra was discussed based on the following different ones： mechanical-interlocking, diffusion bond and coordination bond. The results showed that it was the combined action that played an important role in the effective joining work. Besides, ultrasonic assistance was used in the study to aid welding process based on its high-frequency ultrasonic vibration, which made joints shaping better and improved tensile strength visibly contrast to joints with the same lower heat input parameters.

17-7PH不锈钢小气瓶工艺及性能研究

17-7PH不锈钢制某型号小气瓶由氩弧焊焊接成型,热处理后综合性能得到提升。不同工艺的加工效率、焊接性能、强度差异巨大。综合对比原材料消耗、生产效率、产品性能等因素,最终确定小气瓶半球零件投产采用17-7PH不锈钢4 mm板料,通过拉伸后机械加工成型,小气瓶焊接后通过“TH565”热处理强化实现性能提升,爆破试验失效压力大于85 MPa,爆破断口呈撕裂状,断口微观形貌呈“等轴韧窝”,撕裂过程为典型的塑性断裂。

2A43高强度硬铝合金焊接性能研究

采用真空电子束焊和搅拌摩擦焊对2 mm厚2A43铝合金板材进行焊接试验,并对不同焊接方式接头的显微组织和力学性能进行了对比分析。结果表明,两种焊接方式获得的2A43铝合金接头力学性能均较好,其中搅拌摩擦焊接接头抗拉强度超过母材的90%以上,电子束焊接接头抗拉强度超过母材的80%,搅拌摩擦焊相对较优。真空电子束焊接最优参数为:加速电压60 kV,聚焦电流270 mA,焊接速度450 mm/min,焊接束流11 m A;搅拌摩擦焊最优参数为:搅拌头转速1 300 r/min,焊接速度251 mm/min,焊接倾角4°,轴肩下压量0.5 mm。通过对比发现,焊接热循环使接头显微组织发生了变化,强化相粒子发生再分布是导致接头力学性能差异的重要原因。