扭转试样机夹样系统的改进

针对目前扭转试验存在夹持试样位置不精确，试样装入和卸载工序复杂，和扭转过程易出现夹持偏心等问题，对当前实验室常用扭转试验设备的试验过程和影响因素进行了详细分析，在现有扭转试验机工作原理和结构基础上，提出了夹样系统的改进方案．通过对现有夹持系统增加了顶端限位，压块运动限位和同心圆定位功能，使加载试样定位准确、夹持牢固，简化了扭转实验的装卸流程．通过对低碳钢试样扭转试验，对比改进前和改进后的试验效率和测试结果，发现采用改进后的夹持系统，使加载时间缩短到原来的50％以上，而且测得实验数据更加稳定，提高了扭转实验效率．

Improvement on Fixture Structure of Torsion Tester

For some insufficiences of the current torsion tester, such as inaccurate sample positioning, difficult assembling or disassembling and uncentering clamping, the measurement process and the influences of the torsion test have been analyzed. In addition to the current measurement principle and structure of testing system, an improvement was proposed by adding the top limit, concentric limit and holder-block-moving-range limit. The measurement of low-carbon steel sample has been made. The results show that the new fixture system has advantages of more precise sample positioning,more film sample clamping and easier assembling process. The efficiency of the experiment is improved and the experiment results are stable and reliable.