金属-碳共晶点熔化温坪温度的确定

为了让ITS90温标能够更好地向高温方向传播,利用金属-碳共晶点作为传递标准,其测量结果的不确定度得到了很好的提高,因此,金属-碳共晶点熔化温坪温度的确定就显得尤为重要。本文从转折点熔化温度的定义出发,利用移动平均法,选取二阶差分曲线过零点的值作为熔化温坪温度。本方法避开了人为因素造成的B类不确定度,同时可以消除噪声带来的影响。

Determination of the Melting Temperature of Metal-carbon Eutectic Fixed Point

An important application of metal-carbon eutectic fixed points is their use as transfer standards for high-temperature scale dissemination in ITS90.Using metal-carbon eutectic fixed point as transfer standard can decrease the estimated uncertainty.Therefore,determination of the melting temperature of metal-carbon eutectic fixed point is very important.This paper begins with the definition of inflection point,selects the value of the point passing through zero on the second order difference curve as the melting temperature of metal-carbon eutectic fixed point using the method of moving average.This method avoids the type B uncertainty from person factors and eliminates the influence of noise.