模具失效大多发生于型腔表面，但破坏往往源自表面之下几十微米的范围内，都涉及到表面以下的“表面层”。因此，表面层作为模具的最表层，是模具表面质量的重要组成部分。通过理论建模、数值仿真和实验分析的结合，本项目选择 AISI H13模具钢硬态切削工艺作为研究对象，以切削表面层材料的微观组织演变为出发点，构建基于空间尺度的表面层微观组织与性能的数字化表征模型，建立宏观力学性能与微区力学性能之间的映射关系；通过揭示热—力—相变多物理场耦合作用下的表面层微观组织演变机理，建立宏、微观相结合的表面层微观组织演变模型，实现表面层微观组织及性能的动态模拟和定量预测；最后，基于硬态切削工艺与表面层微观组织及性能之间的映射关系，通过优化切削工艺，实现硬态切削表面层微观组织的可控性演变，获得满足宏观力学性能要求的特定微观组织、微区力学性能及表面层极限厚度，促使硬态切削由“控形制造”向“控形控性制造”跃升。

The failure of the die and mold parts mostly occurs in the cavity surface; however the damages often begin in the range from tens of microns below the machined surface, which are all related to‘surface layer’under the machined surface. Therefore, as the outermost layer of the die and mold parts, the surface layer is an important component part of the surface quality. By means of integrating theoretical modeling, numerical simulation and experimental analysis, hard cutting process of AISI H13 die steel is determined as the research objective. Selecting the microstructure evolution in the machined surface layer of H13 steel as a starting point, the digital representation model about microstructures and performances in the machined surface layer based on the spatial scale and the mapping relationship between the macro-mechanical properties and the micro-zone mechanical properties are established respectively. By revealing the microstructure evolution mechanism in the machined surface layer under the coupling action of the thermo-mechanical-metallo fields, the evolution model about the microstructures in the machined surface layer with the combination of macro-simulation and micro-simulation is proposed, which can achieve a dynamic simulation and a quantitative prediction of microstructures and properties in the surface layer. Finally, based on the mapping relationship between the hard cutting process and the microstructures, and properties in the surface layer, the controllable evolution of the microstructures in the machined surface layer of H13 steel can be achieved by means of optimizing the hard cutting process. The implementation of this project is benefit to getting the specific microstructures, micro-zone properties and limited depth of the surface layer which can meet with the requirements of the macro-mechanical performances, and can promote the hard cutting process to jump from ‘shape controllability manufacturing’ to ‘shape-performance controllability manufacturing’.