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针对连杆轴瓦烧损情况，研究烧瓦对曲轴的影响。采用三维有限元技术计算曲轴的温度场。研究结果表明，由烧瓦所引起的曲轴故障表现为轴颈表面的微裂纹或裂纹。轻微烧死使轴颈处于回火状态，轴颈材料由于具有回火脆性而使冲击韧性显著下降，冷却后较高的残余热应力导致裂纹的产生。剧烈烧瓦使轴颈部分处于淬火状态，恶劣的淬火条件使曲轴冷却后产生很大热应力，淬火热应力超过材料的屈服极限和破断抗力，导致曲轴产生变形甚至开裂。
Aiming at the burning situation of connecting rod bearing bush, the influence of burning bush on crankshaft is studied. Calculate the temperature field of crankshaft with 3D finite element method. The results show that the crankshaft failure caused by the burning bush appears as microcracks or cracks on the journal surface. Slight burned to make the journal in the tempering state, the journal material due to the temper brittleness and the impact toughness decreased significantly, after cooling the higher residual heat stress lead to the generation of cracks. Severe burning of the journal part of the shaft in the quenched state, the harsh conditions of quenching the crankshaft after cooling have a lot of thermal stress, quenching thermal stress exceeds the yield limit of the material and breaking resistance, resulting in crankshaft deformation or cracking.