Investigating the Effect of Al- 1050-H4 Sample Position on Grain Size and Mechanical Properties During Accumulative Roll Bonding Process

Abstract

— Nanocrystalline material polycrystals with grain sizes less than 100 nm—have the unique mechanical properties highly desirable for a wide range of applications. This paper compares the microstructure, grain sizes and hardness of top and bottom Al 1050-H4 rolled samples through an accumulative roll bonding process. The samples were rolled once at the speed of 9 rpm and an applied load of 5 ton. Rolled samples were characterised by optical microscopy and a linear intercept method based on the ASTM E122-12 standard was followed. The hardness test was performed on both samples following the ASTM E384 test standard. Simulation was performed using an Auto Desk Inventor and the mesh sizes of the samples were correlated with their grain sizes to analyse the material properties during the accumulative roll bonding (ARB). The obtained results show more property enhancement under the applied load and strain during the ARB process. The bottom sample was more refined and had higher mechanical properties (hardness) compared to the top sample. The average grain size of the bottom sample was 42.6 µm , and 47.6 µm for the top sample. The hardness results were 51.28 HV for the bottom sample and 42.08 HV for the top sample. From the simulation, it was observed that the elongation was useful, without any possibility of material failure in both 42.6 µm and 47.6 µm microstructural analyses. It was also observed that the elongation during the ARB process occurred without any material defects during the grain refining process. The length of the elongation during the ARB process was also revealed during the simulation process. . Keywords—ARB, properties, elongation, material, samples.