材料热变形行为及测试方法

精密机械零件的受温变形一般是用热膨胀的概念来解释和补偿,而热膨胀系数的不确定性直接影响着补偿的精度.为此,利用一套由机、电、光等设备组成的能够控温、测温及测量几何参数的高精度测量系统,对球体的主要几何参数在5-45℃范围内进行受温变形研究,发现球体直径的热变形系数与形体边界条件无关,认为以球体直径的热变形系数作为材料热膨胀系数的新定义更合理、更精确.

Thermal deformation of the material and its measurement

The precise machine components' deformation is resolved and compensated by thermal expansion, but because of its coefficient's accuracy and the compensated results have a few errors. By using the available precision measuring system composed of mechanical,electrical and optical installation, which can control temperature and measure main geometrical parameters. We study the thermal expansion behavior of the ball square axis under the common range of temperature : 5-45℃ and find that thermal deformation coefficient of ball shape has no connection with the fringe conditions. So a new definition-thermal deformation coefficient, which will take the place of the thermal expansion coef ficient,has been proved to be more rational and accurate.