eprintid: 15200 rev_number: 2 eprint_status: archive userid: 1 dir: disk0/00/01/52/00 datestamp: 2023-11-10 03:29:49 lastmod: 2023-11-10 03:29:49 status_changed: 2023-11-10 01:58:54 type: article metadata_visibility: show creators_name: Soomro, I.A. creators_name: Pedapati, S.R. creators_name: Awang, M. title: Double pulse resistance spot welding of dual phase steel: Parametric study on microstructure, failure mode and low dynamic tensile shear properties ispublished: pub keywords: Dual phase steel; Dynamics; Failure (mechanical); Heat resistance; Heat treatment; Martensite; Scanning electron microscopy; Spot welding; Taguchi methods, Martensitic structures; Mechanical performance; Micro-structural characterization; Optimum conditions; Parametric study; Post weld heat treatment; Resistance spot welding; Single-pulse welding, Heat affected zone note: cited By 8 abstract: Resistance spot welding (RSW) of dual phase (DP) steels is a challenging task due to formation of brittle martensitic structure in the fusion zone (FZ), resulting in a low energy capacity of the joint during high-rate loading. In the present study, in situ postweld heat treatment (PWHT) was carried out by employing a double pulse welding scheme with the aim of improving the mechanical performance of DP590 steel resistance spot weld joint. Taguchi method was used to optimize in situ PWHT parameters to obtain maximum peak load and failure energy. Experiments were designed based on orthogonal array (OA) L16. Mechanical performance was evaluated in terms of peak load and failure energy after performing low dynamic tensile shear (TS) test. Microstructural characterization was carried out using a scanning electron microscope (SEM). The results show that improvements of 17 and 86 in peak load and failure energy, respectively, were achieved in double-pulse welding (DPW) at optimum conditions compared to traditional single-pulse welding (SPW). The improvement in mechanical performance resulted from (i) enlargement of the FZ and (ii) improved weld toughness due to tempering of martensite in the FZ and subcritical heat affected zone (SCHAZ). These factors are influenced by heat input, which in turn depends upon in situ PWHT parameters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. date: 2021 publisher: MDPI AG official_url: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100724412&doi=10.3390%2fma14040802&partnerID=40&md5=cee64758271faaf34dcd35a2708c5cdf id_number: 10.3390/ma14040802 full_text_status: none publication: Materials volume: 14 number: 4 pagerange: 1-19 refereed: TRUE issn: 19961944 citation: Soomro, I.A. and Pedapati, S.R. and Awang, M. (2021) Double pulse resistance spot welding of dual phase steel: Parametric study on microstructure, failure mode and low dynamic tensile shear properties. Materials, 14 (4). pp. 1-19. ISSN 19961944