Mechanical Property Analysis of Flat and Corner Coupons Made from Thick-Walled Rectangular Steel Tube
冷弯厚壁矩形型钢板材力学性能分析

For the sake of providing necessary data for technology improvement, property analysis, structural strength design and validation of numerical simulation, experiment concerning mechanical properties of the flat portion and corner portion and corresponding virgin steel was carried out for thick-walled cold formed steel tube with sectional dimension of 200×300×9.2(mm). Considering cold formed technology and mechanical properties of virgin steel, variation in mechanical character of the flat portion and corner portion with passes was analyzed based on test results. Strain hardening of thick-walled steel in this paper has been compared with that presented in reference 7]. It shows that tremendous difference exists in mechanical properties of flat portion in full cross section. Strength of the flat portion bilateral is lower than that of virgin steel for vertically cold-forming thick-wall rectangular steel tube. Strain-hardening are mainly determined by strength, elongation and strength yield ratio of virgin steel,among which the strength yield ratio is the most important influence factor. High quality strip should be selected as virgin steel to improve end product character.