Experimental Study and Prediction Model of Low Temperature Mechanical Properties of High-Strength Steel

The application of high-strength steel in extremely cold polar regions can reduce steel consumption and save the cost of fabrication, transportation, and installation of steel structures in the harsh low-temperature environment. In order to study the mechanical properties of HG785 high-strength steel under polar low-temperature conditions, uniaxial tensile tests were conducted on high-strength steel coupons by considering two thicknesses and five low-temperature cases. It was found that the elastic modulus, yield strength, and ultimate tensile strength of HG785 high-strength steel in polar low-temperature environment arc higher than those at an ambient temperature of 25 °C. All tensile coupon specimens failed by traditional necking in a ductile manner without brittle failure tendency. Based on the test results, accurate prediction models for mechanical properties of HG785 high-strength steel in polar low-temperature environment were established by the best subset regression analysis. This will facilitate the application of high-strength steel in the design of structural members, joints, and systems in an efficient manner, and provide theoretical support for the promotion of high-strength steel structures in polar low-temperature regions. © 2024 Shanghai Jiaotong University. All rights reserved.