Characterization of Microstructure and Mechanical Properties of Resistance Spot Welded DP600 Steel

Metals

Ali Ramazani³  Krishnendu Mukherjee⁴  Aydemir Abdurakhmanov¹  Mahmoud Abbasi²  Ulrich Prahl⁴ 

[1] Welding and Joining Institute, RWTH Aachen University, Aachen 52072, Germany; E-Mail:;Faculty of Engineering, University of Kashan, Kashan-8731751167, Iran; E-Mail:;Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA;Department of Ferrous Metallurgy, RWTH Aachen University, Aachen 52072, Germany; E-Mails:

关键词: resistance spot welding;    dual-phase steel;    microstructure;    tensile-shear test;    cross-tensile test;    hardness map;    fracture;   

DOI  :  10.3390/met5031704

来源: mdpi

【 摘 要 】

Resistance spot welding (RSW) as a predominant welding technique used for joining steels in automotive applications needs to be studied carefully in order to improve the mechanical properties of the spot welds. The objectives of the present work are to characterize the resistance spot weldment of DP600 sheet steels. The mechanical properties of the welded joints were evaluated using tensile-shear and cross-tensile tests. The time-temperature evolution during the welding cycle was measured. The microstructures observed in different sites of the welds were correlated to thermal history recorded by thermocouples in the corresponding areas. It was found that cracks initiated in the periphery region of weld nuggets with a martensitic microstructure and a pull-out failure mode was observed. It was also concluded that tempering during RSW was the main reason for hardness decrease in HAZ.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.