In the comparative experiments of vibration and non-vibration cast-rolling, it is found that the vibration can significantly enhance the dynamic recrystallization effect in the plastic deformation stage during cast-rolling. In order to explore the strengthening mechanism, the physical simulation experiment and the numerical simulation based on Yada model are used to study the plastic deformation stage of the cast-rolling process. The research results show that the Yada model can accurately calculate the change history of grain size during vibration rolling. It is also found that the vibration frequency can promote the recrystallization nucleation by changing the equivalent plastic strain in the cast-rolling strip during deformation, thereby effectively reducing the average grain size, whereas the amplitude only affects the start time of the dynamic recrystallization. In addition, it is found that vibration can effectively improve the uneven distribution of grain size on the cross section of cast-rolling strip.

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Self-piercing riveting (SPR) has been widely utilized to connect metal components in industry, and the mechanical properties of final product depend on the strength of SPR joint which is experimentally measured through cross-tension and lap-shear tests. These tests are destructive and the tested strength of specimen is not directly related to the actual strength of the SPR product. In this study, the SPR process of aluminum alloy sheet was investigated and the general empirical model of SPR strength was established by comprehensively considering the factors including of the geometric dimensions of components and die, the material properties of rivet and sheet, and the load -stroke curve of punch. The calculated strength values of 4 group of SPR specimens were verified by the experimentally measured results. All 2 / 54 calculation errors are lower than 8%. An industrial internet of things (IIoT) was developed to automatically realize the data transmission and strength calculation of the SPR process.

Self-piercing riveting (SPR) has been widely utilized to connect metal components in industry, and the mechanical properties of final product depend on the strength of SPR joint which is experimentally measured through cross-tension and lap-shear tests. These tests are destructive and the tested strength of specimen is not directly related to the actual strength of the SPR product. In this study, the SPR process of aluminum alloy sheet was investigated and the general empirical model of SPR strength was established by comprehensively considering the factors including of the geometric dimensions of components and die, the material properties of rivet and sheet, and the load - stroke curve of punch. The calculated strength values of 4 group of SPR specimens were verified by the experimentally measured results. All calculation errors are lower than 8%. An industrial internet of things (IIoT) was developed to automatically realize the data transmission and strength calculation of the SPR process.