为提高汽车拉索的拉脱力, 在250 ℃下对汽车拉索35钢接头进行不同时间的保温处理; 通过光学显微镜和扫描电子显微镜等观察热处理后钢接头及其表面镀锌层显微组织的变化, 并进行了拉脱力测试。结果表明: 在250 ℃下随保温时间延长, 钢接头组织中片状珠光体逐渐球化, 使钢接头硬度降低, 塑性变形能力增强, 最小拉脱力增大, 保温6 h后就能达到安全要求标准。

In order to improve the pull-out force of automobile cable, the 35 steel ending fittings were heated at 250 ℃ for different times. The microstructure of the steel ending fitting and the zinc coating on its surface was analyzed by optical microscopy (OM) and scanning electron microscopy (SEM). And the test for pull-out force was examined. Results indicate that with the holding time prolonging at 250 ℃, the pearlite in the microstructure changed from lamellar to spheroidal gradually, which decreased the hardness and enhanced the plastic deformation capacity of the steel end fitting, and then increased the minimum pull-out force. The pull-out force of auto cable could reach the safety requirement after 6 h heat treatment of the steel end fitting at 250 ℃.