半固态固相体积分数的拟合公式

提出了先用抛物线拟合合金液相线和固相线、再用杠杆定律求合金半固态固相体积分数公式的新方法.用新方法求得的Mg-Pb合金半固态固相体积分数公式不仅计算精度高,如Mg-40%Pb合金半固态固相体积分数公式的计算值与测量值的最大绝对误差仅为0.022,而且,因为半固态固相体积分数公式中包含温度和合金元素含量两个自变量,所以扩大了半固态固相体积分数公式的应用范围.

A Fitting Formula for Solid Volume Fraction of Semi-solid Alloy

A new method for calculating solid volume fraction of semi-solid alloy is put forward. In the method the solidus and liquidus are fitted by parabola respectively first, then the equilibrium lever rule is applied to obtain a fitting formula for the solid volume fraction. The fitting formulae for solid volume fraction of Mg-Pb alloys obtained by the new method are of high precision. For example, the maximum absolute error of the solid volume fraction of Mg-40%Pb alloy is about 0. 022 between values calculated by the fitting formula and the values measured. In addition, the application of the fitting formula for the solid volume fraction is extended since the fitting formula contains two variables: temperature and percent of alloy composition.