管状扭力梁横梁性能的对比研究

Comparative Study on the Performance of Tubular Torsion Beam

国内外管状扭力梁横梁的选材主要可分为两类:高强度复相钢和热成形钢。文章针对某一车型开发要求,分别以超高强复相钢CP800和热成形钢22MnB5为原材料,研究不同工艺路线下扭力梁横梁性能的差异。研究结果表明,22MnB5材料横梁拥有更高的强度和表面硬度,横梁本体具有更高的疲劳强度,但焊接后焊缝热影响区软化严重,容易引起失效开裂;而CP800材料横梁有更稳定的焊缝硬度分布,同时兼具较高的强度、硬度,因而拥有更优良的抗疲劳性能。

The material selection of tubular torsion beam at home and abroad can be mainly divided into two categories:high strength complex phase steel and hot forming steel.According to the requirements of a vehicle development,two materials are selected for torsion beam:ultrahigh strength complex phase steel CP800 and hot forming steel 22MnB5.The differences in the performance of torsion beams under different process routes are studied in this paper.The results show that 22MnB5 torsion beam has higher strength and surface hardness.So it has higher fatigue strength in theory.But the weld is easier to fail due to the softening of heat affected zone.The CP800 torsion beam has a stable hardness distribution and high strength and hardness,therefore has a better anti-fatigue performance.