ARB工艺对TA15板材片层球化的影响规律

As one of the methods of severe plastic deformation, accumulative roll bonding (ARB) can refine the grains to sub-micron level. It is also the only method that can greatly improve the comprehensive performance of TA15 sheet while ensuring cost. By studying the influence of the initial TA15 sheet structure, ARB rolling trajectory and rolling reversion on the spheroidization degree of the lamellar structure, the effect of ARB process on the spheroidization of TA15 sheet can be obtained. The results show that when the initial lamella thickness is small and the difference of thickness between grain boundary and intragranular lamellae is small, the lamellar spheroidization is thorough. If the pass deformation of ARB process is too large, the temperature of the TA15 sheet will rise significantly, leading to the uneven spheroidization of the grain boundary and the matrix of TA15. If the pass deformation is too small, it will lead to the incomplete spheroidization of the sheet, and affect the equiaxization effect of the matrix of TA15. With the increase of reversing passes in ARB forming process, uniformity of the sheet increases, the grain size and range of the sheet are further reduced, and the room temperature tensile properties are significantly improved.