Development of Computer-Assisted System for Microstructural Design and Control of Steel

建立了钢的微观组织设计与控制的计算机辅助系统，主要涉及物理性能数据库的建立和相变动力学的计算方法。得到的结果如下：1。建立了铁基合金相图数据库。本文收集了1990年以后的相关论文，并结合ASM国际以前的汇编。这些信息可以通过使用面向对象的数据库系统mood2在Internet上提供全球数据库服务。建立了铁基合金扩散系数数据库。分析了扩散系数与熔点的关系。该方法适用于没有实验信息的扩散数据的估计。建立了铁合金液相的表面能和粘度数据库。给出了估算表面能的计算方法。铁素体中C与合金元素的相互作用对碳钢的蠕变强度有很大影响。基于非线性扩散方程，通过计算机模拟预测了相分解。阐明了磁序和化学序对相平衡的影响。结果表明，磁有序和化学有序的相互作用对相稳定性有显著影响。定量分析了晶界移动时的溶质阻力效应。建立了双相中α相和β相的平均晶粒半径与体积分数的关系。

Computer-assisted system for microstructural design and control of steels has been developed, which is concerned with (i) construction of database of physical properties and (ii) computation al approach of kinetics of phase transformation. The results obtained are as follows.1. The database on phase diagrams of iron base alloys has been constructed. The related papers after 1990 are collected which combines with the previous compilations by ASM International. This information is available for world -wide database service on the Internet by the use of an object-oriented database system MOOD.2. The database on diffusion coefficient of iron base alloys has been constructed. The relation between diffusion coefficients and melting point is analyzed. This method is useful for the estimation of diffusion data where there is no experimental information.3. The databease on the surface energy and viscosity of liquid phase in iron alloys has been constructed. The computational method of estimating surface energy is also presented.4. The interaction between C and alloying elements in ferrite is evaluated and it strongly affects the creep strength of carbon steels.5. Phase decomposition is predicted by computer simulation based on non-linear diffusion equation.6. Effect of magnetic and chemical ordering on phase equilibria is clarified. It is shown that the interaction between magnetic and chemical ordering significantly affects the phase stability.7. Solute drag effect is quantitatively analyzed when the grain boundary is moving.8. The relation between mean grain radii and volume fractions of alpha and beta phases of dual-phase is established.