Microstructural Characteristics of Cu-Fe-P Alloys Severely Deformed by Accumulative Roll Bonding Process

Abstract

The accumulative roll bonding (ARB) process is one of the methods to refine the grain size of metallic materials. The ARB process up to 8 cycles was performed for the pure Cu and Cu- Fe-P (PMC-90) alloy at ambient temperature under no lubricant conditions. In the pure Cu, the nano-sized grains were formed after third cycle with an average grain size of 200nm. Once the 200 nm grains formed, further reduction in the grain size was not observed up to the 8 ARB process cycles. On the other hand, the formation of the stable nano-sized grains in PMC-90 alloy was retarded compared to the pure Cu due to the alloying elements. For both alloys, the tensile strength values increased drastically in the initial stage of ARB process. The tensile strength values of both alloys tended to saturate after the third ARB process cycle. The tensile elongation value greatly decreased by 1 cycle of ARB process due to the strain hardening. After the third cycle of ARB process, each alloy showed a gradual increase in tensile elongation due to the dynamic recovery. For PMC-90 alloy, the strength value is higher than that of OFC due to addition of the alloying elements.