Tensile properties of shielded metal arc welded ultrahigh hard armour steel joints
1Associate Director, Main Battle Tank Division (MBT), Combat Vehicles Research & Development Establishment (CVRDE), Defence Research & Development Organization (DRDO), Avadi, Chennai, INDIA – 600054.
2Professor & Director, Centre for Materials Joining and Research (CEMAJOR) Department of Manufacturing Engineering, Annamalai University, Annamalainagar – (P.O), INDIA – 608002.
3Former Director, Combat Vehicles Research & Development Establishment (CVRDE), Defence Research & Development Organization (DRDO), Avadi, Chennai, INDIA – 600054.
Research Article
World Journal of Advanced Engineering Technology and Sciences, 2020, 01(02), 071-084.
Article DOI: 10.30574/wjaets.2020.1.2.0029
Publication history:
Received on 30 November 2020; revised on 06 December 2020; accepted on 20 December 2020
Abstract:
The present generation Armoured Tracked Vehicles (ATVs) are constructed using Rolled homogenized armour (RHA) grade steels closely confirming with AISI 4340 specifications. However, in future Armoured Tracked Vehicles (ATVs), the overall weight of ATVs has to be reduced enormously and hence, the designers have prescribed to employ Ultra High Hard Armour (UHA) steels for the construction. Welding is considered to be one of the important fabrication methods in ATVs construction. However, welding of UHA steels is highly challenging due to higher hardness and higher carbon content. Shielded Metal Arc Welding (SMAW) is among the most widely employed welding process in the construction of ATVs since it is more versatile and cost-effective. Armour grade steels are welded conventionally using Austenitic Stainless Steel (ASS) consumables to eliminate the serious problems of hydrogen induced cracking. Hence, in this investigation, an attempt has been made to study the influence of ASS welding consumables on tensile properties and hardness of UHA steel joints made by SMAW process. UHA steel plates having 15 mm thickness were welded by SMAW process using five different ASS consumables (having different Creq/Nieq ratio). Tensile properties (unnotched and notched) of the welded joints were evaluated. From this investigation, it was observed that the joint welded using ASS consumable (having higher Creq/Nieq ratio) exhibited superior tensile properties as result of the evolution of ferrite phase with vermicular and globular morphology in the austenite matrix at weld metal region.
Keywords:
Ultra high hard armour steel; Shielded metal arc welding; Austenitic stainless steel consumable; Tensile Properties; Microstructure
Full text article in PDF:
Copyright information:
Copyright © 2020 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution Liscense 4.0