Construction of Materials Database on High Temperature Inelastic Behavior of Metallic Materials and the Application to Numerical Analyses

在包含相变的工程过程（如淬火、焊接、铸造等）中，模拟确定温度、金属组织和应力/应变的耦合场需要大量的材料数据；热传导的导热系数和比热，CCT或TTT图，相变的温度膨胀图，应力-应变本构关系，弹性常数，所有这些都依赖于温度。本项目配合日本材料科学学会工程塑性委员会材料数据库分委员会的活动，推动材料数据库的建设，并对数值模拟的有效性和适用性进行评估。本文针对50多种热处理用钢，积累了以下材料数据，这些数据来自文献和实验；5%应变下的应力-应变曲线，导热系数，比热，弹性模量，CCT和TTT图，温度-延伸图。建立在MS-Excel上的数据库工具采用分层结构设计，方便用户使用，并将开发的数据库中的资料数据转换为MATEQ数据库。该数据库包含1000多种s-s曲线的数据序列和50-100种其他属性的数据序列，这将引发未来更复杂的数据库的发展。通过对几种相变过程的模拟，验证了该数据库的有效性和数值模拟的适用性。

Simulation to determine coupled fields of temperature, metallic structure and stress/strain in the course of engineering processes incorporating phase transformation, such as quenching, welding, casting and so on, needs so many material data ; thermal conductivity and specific heat for heat conduction, CCT or TTT diagram, temperature-dilatation chart for phase change, and Stress-strain constitutive relation, elastic constants, all of which depend on temperature. This project motivates the construction of a materials database cooperating with the activity of Subcommittee of Materials Database, Committee of Engineering Plasticity, the Society of Materials Science, Japan, and the evaluation of the validity and applicability to numerical simulation. More than 50 kinds of steel used for heat treatment are focused here to accumulate the following material data, which are taken from documents and experiments ; stress-strain curve under 5% strain, thermal conductivity, specific heat, elastic modulus, CCT and TTT diagram, temperature-elongation diagram. The database tool built on MS-Excel is designed in a hierarchical structure so that users can easily approach, and the material data in the developed database are converted to a database, MATEQ.This database contains more than 1000 kinds of data series for s-s curves and 50-100 for other properties, which triggers future development of more sophisticated database. The validity of the database and applicability to numerical simulation is also examined by simulating several kinds of processes with phase transformation.