Investigation of combined influence of skin pass rolling and roller straightening of a thin sheet made of materials with different crystal lattice on microstructure, texture, static and fatigue strength

平整轧制和轧辊矫直代表了板材生产的最终操作，并决定性地决定了产品的组织和机械性能。初步研究表明，这些成形操作的影响强度除其他外取决于材料的晶格结构。平整轧制单调成形导致材料加工硬化，轧辊矫直循环成形，加工硬化或加工软化对板材性能的综合影响有待进一步研究。由于板材零件在后续加工过程中不仅承受静态应力，而且还承受循环机械应力，因此除了加工硬化或软化外，残余应力状态也具有重要意义。因此，需要对材料在静应力和循环应力下的力学性能进行全面的表征。计划项目的工作计划包括分析静应力和循环应力下力学性能的变化，以及研究不同平整和辊矫直条件下板材的组织和织构，包括包辊的S形状。该研究项目的科学目的是在静态和循环实验的框架内，研究不同晶格材料(DC01、Cu、Alpha-Ti)板材在平整过程中的单调成形和在辊弯矫直过程中的循环成形对板材的组织、织构、残余应力水平和标志以及力学性能的影响。该项目的实际目标是开发一种合适的技术，通过适当结合平整轧制的单调成形和辊弯矫直的循环成形条件，生产具有载荷可调的组织、织构和高静态强度和疲劳强度的板材。

Skin pass rolling and roller straightening represent the final operations in sheet production and decisively determine the resulting microstructural and mechanical properties of the products. In preliminary investigations, it was shown that the intensity of the influence of these forming operations depends inter alia on material lattice structure. Further investigation is required on the combined influence on sheet properties as a result of monotonous forming by skin pass rolling which induces material work hardening and cyclical forming by roller straightening, which could induce either work hardening or work softening. Since sheet metal parts are subject to not only static but also cyclical mechanical stresses in later operations the residual stress state is of essential significance in addition to work hardening or softening. Thus, a comprehensive material characterization is required concerning mechanical properties during static and cyclical stresses. The work programme of the planned project includes the analysis of changes in mechanical properties during static and cyclical stresses as well as the investigation of microstructure and texture of sheets during various skin pass rolling and roller straightening conditions including the s-shape enclosing the rolls. The scientific aim of the planned research project is the investigation of combined influence of monotonous forming during skin pass rolling and cyclical forming during roller straightening of sheets made of materials with different crystal lattices (DC01, Cu, Alpha-Ti) on microstructure, texture, the level and sign of residual stresses, and the mechanical properties within the framework of static and cyclical experiments. The practical aim of the project is the development of an appropriate technology for production of sheets with load-adjusted microstructure, texture, and a high static and fatigue strength by a suitable combination of monotonous forming by skin pass rolling and cyclical forming by roller straightening conditions.