Effect of Post Weld Heat Treatment on the Microstructure and Mechanical Properties of a Submerged-Arc-Welded 304 Stainless Steel

Abstract

Abstract:The present study is to investigate the effect of post heat treatment on the microstructures and mechanical properties of a submerged-arc-welded 304 stainless steel. The base material consisted of austenite and long strips of delta-ferrite surrounded by Cr-carbide, and the welds consisted of delta ferrite and austenite matrix. For the heat treatment at 850 • C or lower, Cr-carbides were precipitated in the weld metal resulting in the reduction of elongation. The strength, however, was slightly reduced despite the presence of Cr-carbides and this could possibly be explained by the relaxation of internal stress and the weakening of particle hardening. In the heat treatment at 1050 • C, the dissolution of Cr-carbide and disappearance of delta ferrite resulted in the lower yield strength and higher elongation partially assisted from deformation-induced martensitic transformation. Consequently, superior property in terms of fracture toughness was achieved by the heat treatment at 1050 • C, suggesting that the mechanical properties of the as-weld metal can be enhanced by controlling the post weld heat treatment.

Performance Evaluation of the Effects of Post Weld Heat Treatment on the Microstructure, Mechanical and Corrosion Potentials of Low Carbon Steel

“…Earlier work has studied the effect of PWHT on the mechanical properties of medium carbon steel, high strength steels stainless steels and some aluminium alloys. The effect of post heat treatment on the microstructures and mechanical properties of a submerged-arc-welded 304 stainless steel by [8]. The results obtained showed that after heat-treatment, the pre-existing strips in the base metal was dissolved into austenite and the delta-ferrite of the weld metal was transformed into austenite, leading to the microstructure close to the austenite single phase.…”

Microstructure and Mechanical Properties of Structural Metals and Alloys

“…A total of 22 papers cover a ranger of structural metals and alloys. The major portion of these papers is focused on the mechanisms of microstructure evolution and the mechanical properties of metallic materials subjected to various thermo-mechanical, deformation, or heat treatments [1][2][3][4][5][6][7][8][9][10][11][12]. Another large portion of the studies is aimed on the elaboration of alloying design of advanced steels and alloys [13][14][15][16].…”

“…Those readers interested in structural steels may learn much from comprehensive investigations of microstructural changes and their effect on mechanical properties caused by plastic working and heat treatment of diverse steel types [2,7,8,10,12,15,16,[19][20][21][22]. Two of these papers [7,12] present experimental/simulation results of mechanical behavior of high-Mn TWIP steels, which have recently aroused a great interest among material scientists and engineers because of outstanding strengthductility combination inherent in such steels.…”

“…Two of these papers [7,12] present experimental/simulation results of mechanical behavior of high-Mn TWIP steels, which have recently aroused a great interest among material scientists and engineers because of outstanding strengthductility combination inherent in such steels. Some crucial features of structure-property relations are detailed for advanced heat resistant [10,15,19,22] and stainless [8,21] steels. Materials scientists working with aluminum alloys may find many interesting results for dispersion strengthening, including processing, structural/precipitation analysis, and mechanical testing [13,17,18].…”

“…The great diversity of materials, which are presented in this special issue, involves various techniques of their production. Worthy of mention are severe plastic deformation [5,9] and welding [8,10] as topics of quickened interest. As a guest editor, I sincerely believe that every reader among materials scientists will find interesting and useful information in the present special issue.…”