An experimental study on fracture toughness of resistance spot welded galvanized and ungalvanized DP 450 steel sheets used in automotive body

Authors

  • Ibrahim Sevim Mersin University, Engineering Faculty, Department of Mechanical Engineering

DOI:

https://doi.org/10.3989/revmetalm.072

Keywords:

DP steels, Fatigue, Fracture Toughness, Resistance Spot Welding (RSW)

Abstract


The purpose of this study is to determine fracture toughness of Resistance Spot Welded (RSW) Dual Phase (DP) steels. RSW of galvanized and ungalvanized DP 450 steel sheets was carried out on spot welding machine. Fracture toughness of RSW joints of galvanized and ungalvanized DP 450 steel sheets was calculated from tensile-shear tests. New empirical equations were developed using Least Squares Method (LSM) between energy release rate, fracture toughness and critical crack size depending on the relationship between hardness and fracture toughness values. Results indicated that fracture toughness of joints welded by using RSW increased exponentially while the hardness decreased. In addition, fracture toughness and energy release rate of RSW galvanized DP 450 steel sheets were lower compared to RSW ungalvanized DP 450 steel sheets which had approximately the same hardness.

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Published

2016-09-30

How to Cite

Sevim, I. (2016). An experimental study on fracture toughness of resistance spot welded galvanized and ungalvanized DP 450 steel sheets used in automotive body. Revista De Metalurgia, 52(3), e072. https://doi.org/10.3989/revmetalm.072

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Section

Articles