CAJ | 학술논문

特种车辆在恶劣环境下试车，发现连接转向节与下横臂的球头销发生开裂。对失效球头销外观及断口进行宏微观观察，并对材料金相组织、硬度、化学成分进行检查和分析，确定了球头销的开裂性质及失效原因。研究结果表明，球头销为双向弯曲疲劳开裂。球头销颈部无淬硬层，使得其疲劳抗力不足，是导致其疲劳开裂的原因之一；球头销转动不良，存在较大的阻力，使其颈部受力增大，是导致疲劳开裂的又一因素。
특충차량재악렬배경하시차，발현련접전향절여하횡비적구두소발생개렬。대실효구두소외관급단구진행굉미관관찰，병대재료금상조직、경도、화학성분진행검사화분석，학정료구두소적개렬성질급실효원인。연구결과표명，구두소위쌍향만곡피로개렬。구두소경부무쉬경층，사득기피로항력불족，시도치기피로개렬적원인지일；구두소전동불량，존재교대적조력，사기경부수력증대，시도치피로개렬적우일인소。
After endurance testing of a vehicle, a bulk pin was found to have cracked. In this paper, macro and micro observation on the bulk pin were carried out. Hardness and chemical composition were tested. The results indicate that the crack of the bulk pin is bi-directional bending fatigue crack. The neck position of the pin did not have hardened layers, resulting in lower fatigue resistance. Another cause for the failure is that the pin couldn’ t rotate smoothly, which increased the applied force around the neck of the pin.