Study On Energy Absorption Performance Of Varying Strength Thin-walled Metal Tubes

With China's rising car ownership, car accidents often occur. It is an important means to reduce the loss of the accident that the body can increase the absorption effect with a thin-walled tubes. Therefore, it is necessary to develop energy-absorbing effect of a good novel thin-walled tubes. Usually thin-walled tube are of equal strength, due to the deformation mode of instability, the need for pre-suppression induced groove. If the partition hardening treatment strength thin-walled tube, prepared and non-existence quench quenching zone spaced longitudinal direction of the pipe member, since its regional differences in mechanical properties, deformation mode and energy absorption effect will vary greatly. In this paper, experimental research and numerical simulation studies on the strength of this new variant of thin-walled tubes.Selection DP590 and HC260LA, induction heating equipment to its local area is heated to austenitizing temperature, then add salt water quenched, obtaining a variable strength of thin-walled tubular member. This thin-walled tubes can be divided into three regions hardness increases, that original tissue area, heat affected zone and quench zone. Since lath martensite generated in the quenching zone, so the yield and tensile strength are improved. The yield strength DP590 quench zone increase 48%-52%29%-31% tensile strength, yield strength HC260LA is increased by 52%-61%, the tensile strength by 65%-73%.On the 100t universal testing machine, and so on the strength of the original thin-walled tube with the new variable strength of thin-walled tubular member quasi-static compression tests to examine their mode of deformation and energy absorption effect. Experimental results show that compared equal strength thin-walled tube, thin-walled tubular member having a varying intensity better mode of deformation and energy absorption effect. DP590 material strength of thin-walled tube becomes maximum total energy absorption by 72%, the maximum load average increase of 72%. HC260LA material becomes strength of thin-walled tube maximum total energy absorption by 38%, the maximum load average increase of 37%.Use LS-DYNA software for thin-walled tube was prepared deformation modes and energy absorption effect of dynamic compression numerical simulation and analysis. The simulation results show that the deformation always starts from the original tissue area. Variable strength of thin-walled tubular member organizations in the region to play an original role in inducing groove, by optimizing the distribution of the original structure zone and quench zone, control the timing and magnitude of peak force occurs, in order to optimize the entire collision effects.Variable strength of thin-walled tube simple preparation, compared with inducing grooves equal strength thin-walled tube of low cost, so there is a good prospect in the future structure of the thin-walled automotive energy-absorbing member.