铁含量对K418合金TCP相析出规律的热力学分析

Thermodynamics Analysis of Fe Content on the Precipitation Regularityof TCP Phase in K418 Alloy

利用Thermo-Calc软件热力学计算得出铁含量对K418合金的TCP相析出规律的影响。结果表明:K418合金析出相为MC相、M23C6相、γ相、γ′相、σ相、μ相、α-Cr相、M3B2相和液相。随着铁的质量分数从2.5%降至0%,碳化物、硼化物、液相线的含量变化较小,有少量α-Cr相析出。为减少K418合金TCP相析出,铁的质量分数建议控制在1.25%以下,无σ相析出且TCP相含量较少。实际生产中制定K418合金铁含量的目标值还需考虑设备状况和冶炼烧损量。

The effect of Fe content on the precipitation regularity of TCP phase was studied by the calculation results of Thermo-Calc software. The results indicated that the precipitation phase of K418 alloy was MC phase, M23C6 phase, γphase, γ＇ phase, a phase, μ phase, a-Cr phase, M3B2 phase and liquid phase. The content of carbide, boride and liquid phase was almost no change and the content of a-Cr phase was little as the Fe content was between 2.5 % （mass fractions） and 0 %. For decreasing TCP phase content of K418 alloy, the Fe content was below 1.25 （mass fractions）, the σ phase was disappear and the content of TCP phase was lowest. But the target value of Fe element was also considered equipment status and melting loss.