摘要
为了研究焊接时间对WC-10Co硬质合金/RM80高强度钢电阻焊接头性能的影响,采用电阻焊工艺在10~50 ms的焊接时间范围制备对接接头,通过剪切试验、SEM、EDS及金相显微镜系统测试接头强度、宏观形貌、微观组织及元素分布.结果表明,随焊接时间延长,接头剪断力先升后降,40 ms时达到峰值1 466.1 N;时间进一步增加至50 ms,飞溅加剧,强度回落至1 123.8 N;热影响区宽度与挤出熔核体积均呈先增后减趋势,40 ms时最大.微观组织显示,过短时间界面未充分结合,过长则造成金属飞溅、Co粘结相溶解流失, Fe,Co和W元素扩散距离随时间增加而增大,Ni镀层随时间增大而完全熔化,但50 ms时因能量过剩出现孔洞与裂纹.综合判定,40 ms为获得高抗剪强度、缺陷最少的最优焊接时间.
To clarify the effect of welding time on the performance of WC-10Co cemented carbide/RM80 high-strength steel joints by resistance welding,butt joints were prepared in the welding time range of 10~50 ms by employing the resistance welding process.The joint strength,macro-morphology,microstructure,and elemental distribution were systematically investigated by shear test,SEM,EDS,and metallurgical microscopes.The results show that with increasing welding time,the joint shear force first increases and then decreases,reaching a peak value of 1466.1 N at 40 ms.When the time is further extended to 50 ms,spattering becomes severe,and the strength drops back to 1123.8 N.Both the width of heat-affected zone and the volume of the extruded nugget exhibit an initial increase followed by a decrease,attaining their maxima at 40 ms.Microstructural observations indicate that an unduly short time leads to insufficient interfacial bonding,whereas an excessive time causes metal spattering and dissolution/loss of the Co binder phase.The diffusion distances of Fe,Co,and W elements increase with welding time.The Ni coating is completely molten as the time is prolonged,yet excess energy induces porosity and cracks at 50 ms.By taking all factors into account,40 ms is identified as the optimal welding time that provides the highest shear strength together with the fewest defects.
作者
谭振钧
李远波
何浩
徐洋
TAN Zhenjun;LI Yuanbo;HE Hao;XU Yang(School of Mechanical and Electrical Engineering,Guangdong University of Technology,Guangzhou 510006,China)
出处
《焊接学报》
北大核心
2026年第2期98-104,共7页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(52075104)
广州市重点实验室专项资助项目(201605030007)。
关键词
异种金属焊接
精密电阻焊
焊接时间
剪断力
微观组织
dissimilar metal welding
precision resistance welding
welding time
shear force
microstructural
