15Cr系高铬铸铁组织特征的热力学分析

利用Thermo-Calc软件对不同铬碳比的15Cr系高铬铸铁凝固过程、平衡相数量及其组成进行了查证和计算,在此基础上揭示了该类铸铁的组织特点及其影响因素.结果表明,15Cr系高铬铸铁的铸造工艺性能和平衡相数量及其组成均可通过铬碳比这一指标进行调节,而影响其二次碳化物析出和共析转变过程的主要因素是冷却条件;铬碳比的选择应根据高铬铸铁的服役条件而定.Thermo-Calc软件预测结果与实际情况基本上相符,结论可用于指导该类产品的研究与开发.

Thermodynamic Analysis on Microstructure Characteristics of 15Cr System High Chromium Cast Iron

A series of verifications and calculations of solidification courses,equilibrium phase fractions and their compositions for 15Cr system high chromium cast iron with different ratios of chromium content to carbon content were carried out using Thermo-Calc software,and the microstructure characteristics and its influencing factors of the cast iron were illustrated based upon above equilibrium phase calculations.The results indicate that it's feasible for the adjustments of foundry technology performance,equilibrium phase fractions and their compositions for 15Cr system high chromium cast iron may be made by varying the ratio of chromium content to carbon content in the cast iron.Furthermore,the secondary carbide precipitation and the eutectoid transformation in the cast iron depend mainly on specific cooling condition.The selection of the ratio of chromium content to carbon content in 15Cr system high chromium cast iron has to be made in accordance with the specific working environment where the cast iron is used.The predictions obtained with Thermo-Calc software are primarily in agreement with the available experiments and provide the theoretical basis on the production and employ of the cast iron.