Effect of shot particle conditions on the transfer of copper induced by fine particle peening

Author:  Y.Kameyama, R.Takahashi, Y. Owaku, H. Sato, and R. Shimpo
Source:  Conf Proc 2014: ICSP-12 Goslar, Germany (pgs.450-455)
Doc ID:  2014119
Year of Publication:  2014
Abstract:  
Fine particle peening (FPP) is a promising technology to improve fatigue life of mechanical components. In addition, transfer of shot particle elements from the particle to the treated surface occurs during the FPP process. This phenomenon is effective to modify the surface characteristics by concentrating the transferred elements onto the treated surface. In this paper, the authors carried out FPP to enrich the aluminum and steel substrate with copper, which has lots of attractive properties such as high electric conductivity, high thermal conductivity, antibacterial properties, and so on. Two types of hybridized particles which comprised the steel particle and overlying copper layer were developed to accelerate the transfer. The one was "agitated particles" prepared by mechanical mixing using the mortar, and the other was "coated particles" prepared by electroless copper deposition. FPP-treated surface with the hybridized particles and the commercial copper particles were prepared and characterized to discuss the effect of shot particle conditions on the transfer phenomena. Results indicated that the amount of copper transferred by FPP using the hybridized particles, especially the "coated particles", was greater than that by using copper particles. The hybridized particles enhanced the transfer of copper since the impact of hard steel particles effectively expose the virgin metallic surface, accelerating the bonding between the substrate and particles. Ability of the hybridized particles to induce transfer was correlated with the hardness ratio between the substrate and the particles. It was revealed that the hybridized particles were beneficial for FPP to induce transfer of low hardness material.