灰铸铁热分析技术的算法研究

Algorithm of Thermal Analysis for Gray Cast Iron

热分析法是广泛应用于分析铁水成分、保证铸件性能的重要手段,其关键技术在于如何准确获取铁水固液相线温度(TL/TE)。基于铁水冷却曲线与铁碳平衡相图对应关系的分析,提取铁水固液相线特征的不同描述:拐点和平台,进而提出了基于拐点特征和平台特征的算法,获取铁水初晶温度(TL)和共晶温度(TE)。数据预处理技术涉及在VC++环境下调用Matlab小波分析函数,去除原始数据的噪声干扰。通过实验验证、分析两种算法的优劣,提出了一种合理的组合方案:初晶温度使用拐点算法,共晶温度使用平台算法。

Thermal analysis is widely used in the molten iron composition to guarantee the casting properties. Its key technology lies in obtaining liquidus and solidus temperature （TL/TE） accurately. Based on the analysis of corresponding relationship between the molten iron cooling curve and the iron carbon equilibrium phase diagram, the different descriptions of features about the molten iron TL/TE： inflexion point and platform are extracted. Besides, this paper proposes that the algorithm of the inflexion point feature and platform feature are used to determine TL and TE. Then the preprocessing data and wavelet analysis functions of Matlab are called to eliminate the noises in the raw data under the environment of Visual C＋＋. A rational combination scheme, inflexion point algorithm for TL and platform algorithm for TE, is proposed by analysing both algorithms based on experiments.