两种膨胀系数热变形计算误差分析

Error Analysis of Thermal Deformation Calculating of Two Kinds of Expansion Coefficient

本文从热膨胀系数基本定义出发对热变形计算进行了较深入分析。理论上建立了平均线膨胀系数同瞬间线膨胀系数计算热变形的误差数学模型 ,并通过实验论述了精密工程应用中使用平均线膨胀系数计算的工件热变形误差较大 ,提出广泛使用瞬间热膨胀系数替代平均线膨胀系数是提高机器设备精度的发展趋势。

The thermal deformation calculation on base definition of expansion coefficient is analyzed. The mathematics model of immediate thermal deformation with mean coefficient of linear thermal expansion and thermal expansivity is built. It is demonstrated that the error of thermal deformation with mean coefficient of linear thermal expansion is more high, so that it is certain trend to use immediate thermal expansivity instead of mean coefficient of linear thermal expansion to improve the instruments accuracy in precision engineering.