Process adjustments to improve fracture behaviour in resistance spot welds of ehss and uhss

被引：0
作者：
Mimer M. [1 ]
Svensson L.E. [1 ]
Johansson R. [2 ]
机构：
[1] Volvo Truck Corporation,
[2] Volvo Car Corporation,undefined
来源：
Welding in the World | 2004年 / 48卷 / 3-4期
关键词：
Experiment design; Failure; Fractures; Hardness; Heat treatment; High strength steels; In Process Tempering; Martensite; Peel tests; Practical investigations; Resistance welding; Simulating; Spot welding; Spot welds; Tempering; Tensile tests; Welded joints;
D O I：
10.1007/BF03266421
中图分类号：
学科分类号：
摘要：
In recent years new types of sheet steels, combining higher strength with better ductility have been developed. Some of these steels have shown limited weldability compared to mild steels. The hardness of the welds for these steels stretches from 380 HV for DP 600 to approximately 500 HV for TRIP (Transformation Induced Plasticity) and boron steels. Static peel tests of eight types of steels resulted In plug failures for the DP 600 steels, but some Interfacial failures for higher strength steels. Generally, welds with a hardness exceeding 400-450 MV caused unstable fractures. To modify the hardness of the weld an in-process tempering of weld martensite was performed on a TRIP steel. Guidance to a proper tempering pulse was obtained through simulation of phase transformation and cooling of the weld. Welding experiments showed that the weld hardness could be reduced to approximately 350 HV, i.e. below the limit where interfacial failures start to occur.
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页码：14 / 18
页数：4
相关论文
共 4 条
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  • [2] Peterson W., Dilution of Weld Metal to Eliminate Interfacial Fractures of Spot Welds in High and Ultra High Strength Steels
  • [3] Chuku W.L., Gould J.E., Development of appropriate resistance spot welding practice for transformation-hardened steels, Welding Journal Research Supplement, (2002)
  • [4] Eliasson M., Improvement of Mechanical Properties of Laser-welded Trip 700
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