Effect of Laser Power on Mechanical and Microstructure Properties of Pulsed Nd:YAG Laser Welded Dissimilar DP600-DP1000 Steel Sheets

Year 2020, Volume: 4 Issue: 1, 41 - 46, 20.03.2020

Oğuz Tunçel , Hakan Aydın , Şükriye Çetin

https://doi.org/10.26701/ems.632173

Cited By: 1

Abstract

In the present study, dissimilar dual-phase
(DP) steel sheets (DP600-DP1000) were double-sided welded with Nd:YAG
(Neodymium-doped Yttrium Aluminum Garnet (Y3Al5O12)) laser device and the
effect of laser power on mechanical and microstructural properties of welded
sheets was investigated. Laser welds were conducted using SISMA SWA300 Nd:YAG
laser welding machine in the flat position with the butt joint. DP600 and
DP1000 steels with a 1 mm thickness were selected for the experiments. Laser
power was changed from 20% to 75%, and other welding parameters were kept
constant. To evaluate the welded samples, tensile, microhardness and optical
microscope tests were performed. As a result of the study, in high laser power
values, good quality welds were obtained. In microstructural studies, it was
observed that three different regions were formed in the weld section; fusion
zone (FZ), heat affected zone (HAZ) and base material (BM). These three regions
were composed of different phase structures; FZ: martensite, bainite and
retained austenite, HAZ: martensite, bainite, ferrite, retained austenite and
tempered martensite, BM: ferrite and martensite. Also, different hardness
values were measured in these different regions, particularly in the FZ highest
microhardness values were measured due to effective martensite formation.

Keywords

Pulsed Nd:YAG laser welding, DP600 steel, DP1000 steel, Laser power, Mechanical properties, Microstructure

Supporting Institution

Bursa Uludağ Üniversitesi Bilimsel Araştırma Projeleri Birimi

Project Number

HDP (MH) 2017/47

Thanks

This study is supported by the Scientific Research Fund (BAP) of Uludag University

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