乘用车轮毂轴颈承载能力研究

Hub journal capacity of passenger wheel hub journal

针对乘用车轮毂轴颈在终端客户使用处频繁断裂的问题,对轮毂轴颈断裂失效的原因进行了分析,并进一步对轴颈在不同热处理工艺条件下的承载能力进行了研究。首先,系统分析了现有乘用车轮毂轴颈断裂的原因,并对该断裂模式进行了评价,提出了优化的方向;然后,对轴颈开展了4种热处理工艺条件下的样件试制与性能参数测定;最后,对4种热处理工艺状态轴颈的承载能力进行了静压、冲击、刚性、疲劳强度对比试验与分析。研究结果表明:相比于表面采用淬回火处理的轮毂轴,未做表面淬回火处理的轴颈,其静载承受能力提升了60%,抗冲击能力提升了至少26%,且疲劳强度寿命的离散性有所下降,同时在1.2 G载荷条件下,轮毂轴也能够满足无塑性变形的技术要求;采用新工艺对轮毂轴颈实施量产后,在实际应用中完全杜绝了轮毂轴颈断裂安全事故的发生。

Aiming at the problem of the frequent hub axle breakage of passenger vehicle hub axle at the end customer s use,the fracture causes of hub axle was analyzed and investigated,and the hub axle loading capability under different heat treatment process conditions was further studied.First,the cause of the fracture of the existing passenger vehicle hub axle was systematically analyzed,the fracture mode was evaluated,and the optimization direction was proposed.Then trial production and performance measurement of the hub axle samples under four type heat treatment conditions were carried out.Finally the static pressure,impact,stiffness,fatigue strength comparative test and analysis of the hub axle loading capacity under four type heat treatment conditions were carried out.The study results show that:compared with the hub axle whose surface is quenched and tempered,static load bearing capacity of the hub axle without surface quenching and tempering is increased by 60%,and impact resistance is increased by at least 26%,and dispersion of fatigue strength life is decreased,at the same time,the technical requirement of no plastic deformation under 1.2 G load conditions can be meet.After the process improvement is carried out,the fracture safety accident is completely eliminated in practical applications.