我厂曾在GA7605和自制车沟槽的机床上,发现车制轴承内套圈的外径和小圈沟槽的夹具上的拉杆芯子,特别是螺纹部分(拉杆芯子φ14mm,45号钢,螺纹部分φ6mm不淬火)大批断裂(图1)。有的拉杆芯子装上后,机床运转进行切削时就断裂,有的使用不久也突然断裂。由于拉杆芯子大批断裂,不仅降低了夹具的使用寿命,而且严重地影响了生产。为此进行了断口分析和金相分析。 I plant in GA7605 and self-made car groove machine tools and found that the outer diameter of the car bearing rings and small groove groove clamp on the rod core, especially the threaded part (rod core φ14mm, 45 steel , Threaded part of φ6mm not quenching) a large number of fracture (Figure 1). Some rod core loaded, the machine running cutting fracture, and some suddenly rupture soon after use. As the rod core mass rupture, not only reduces the service life of the fixture, but also seriously affected the production. For this reason, fracture analysis and metallographic analysis were carried out.