Weldability of Dual Phase Steel Containing Boron

• Published in: Key engineering materials 2020-03, Vol.835, p.251-264
• Main Authors: Khafagy, Sameh M., Farahat, Ahmed Ismail Zaky, Morsy, Morsy Amin
• Format: Article
• Language: English
• Subjects: Base metal; Boron steels; Carbon steels; Dual phase steels; Duplex stainless steels; Electron beam welding; Heat affected zone; Heat treatment; Hot forging; Martensite; Mechanical properties; Metallurgy; Microstructure; Shielded metal arc welding; Steel plates; Ultimate tensile strength; Welded joints
• ISSN: 1013-9826; 1662-9795; 1662-9795
• DOI: 10.4028/www.scientific.net/KEM.835.251

Carbon steel containing boron-dual phase was produced by casting and were heated to 1200 °C for hot forging to produce plates of 10 and 6 mm thick. The plates produced were heated to the inter-critical annealing temperature for 15 min. and then water quenched followed by tempering process. The microstructure of the produced steel is ferrite with islands of martensite. Welding was done to the heat treated steel plates (6mm) using SMAW process and applying AWS-E11016 electrode and as a result an over-tempered region in the heat affected zone was formed with a significant reduction of the ultimate tensile strength of the welded joint. Reduction of heat input resulted in an increase in the joint strength. Welding of the hot rolled plates with a subsequent heat treatment resulted in formation of homogenous joint with good mechanical and metallurgical properties. Application of Electron Beam Welding to this dual phase steel resulted in a welded joint with good mechanical properties comparable to that of the base metal. The results were discussed based on microstructure analysis and hardness distribution of the welded joints.