A Study of Spot Welding of Advanced High Strength Steels for Automotive Applications
The application of advanced high strength steels in automotive industry has highlighted the need for research into spot weldability of these steels. Using weld lobe diagrams, the spot weldability of DP600 steel was found to be poor with conventional weld schedules. An enhanced weld schedule consisting of two pulses with reduced current on the second pulse gave a substantial increase in the lobe width; the first pulse removed the zinc coating and the second pulse controlled the nugget growth. A data acquisition system was designed to monitor weld expulsion during the weld operation. Of the three possible control strategies proposed, especially with AC welding equipment, the dynamic resistance signal is easily obtained and the least expensive. Expulsion phenomena, microstructural characterization and mechanical properties of spot-welded hot dipped galvanized DP600 steel and interstitial free steel were investigated. Further work on dissimilar welds in DP 600 and HSLA 350 was also conducted with emphasis on tensile and fatigue properties and fracture characteristics. The performance of dissimilar spot welds was different from that of the similar spot welds in each of the HSLA350 and DP600 steels. The DP600 weld properties played a dominating role in the hardness and tensile properties of the dissimilar spot welds. However, the fatigue performance of the dissimilar welds was similar to that of the HSLA welds. Details will be presented at the conference.
Resistance spot welding Dynamic resistance Nugget diameter and Hardness Dissimilar materials Microstructure Mechanical properties Fatigue Fracture mode
BHOLE S.D. MA C. KHAN M.S. CHEN D.L.
Department of Mechanical and Industrial Engineering, Ryerson University,350 Victoria Street,Toronto, ON,M5B 2K3,Canada
国际会议
The 6th International Conference on High Strength Low Alloy Steels(第六届高强度低合金钢国际会议HSLA Steels2011)
北京
英文
362-367
2011-05-31（万方平台首次上网日期，不代表论文的发表时间）