Effects of Welding Processes on the Low Temperature Impact Toughness of Structural Steel Welded Joints

Abstract

ABSTRACT： In this study, the Charpy impact test along with metallurgical observation was conducted to evaluate low temperature impact toughness of structural steel welds with different welding processes to find out the optimal welding process to guarantee the required impact toughness at low temperatures. The welding processes employed are shield metal arc welding (SMAW) and flux cored arc welding(FCAW), which are commonly used welding methods in construction. The Charpy impact test is a commercial quality control test for steels and other alloys used in the construction of metallic structures. The test allows the material properties for service conditions to be determined experimentally in a simple manner with a very low cost. To investigate the impact toughness at low temperatures of the steel welds, specimens were extracted from the weld metal and the heat affected zone. Standard V-notch Charpy specimens were prepared and tested under dynamic loading condition. The low temperature impact performance was evaluated based on the correlation between the absorbed energy and the microstructure. Analysis of the results showed that the optimal welding process to ensure the higher low temperature impact toughness of the HAZ and the weld metal is SMAW process using the welding consumable for steels targeted to low temperature use.

A Study of Mechanical Properties Evaluation for Stainless Steel Under Low Temperature Region

“…[1] The adoption of materials for machinery and parts requires the use of superior materials with high strength and cold shock characteristics especially in extreme regions, usually, the temperature reaches at -20°C in wither, such as Eastern Europe, northern Russia, and Canada. [2][3] In the case of stainless steels used in low-pressure pressure vessels with corrosion resistance, studies have been conducted to evaluate the mechanical behavior in high-temperature environments and the mechanical behavior of some super-duplex steels in low-temperature regions. However, austenitic stainless steel's mechanical behavior at low temperatures has not been studied.…”