Effect of swaging and mechanical surface treatments on the mechanical properties of the spray-formed ultra high strength copper alloy CuMn20Ni20

摘要

The precipitation hardened ordered copper-based alloy CuMn20Ni20 is used as a non-magnetic high strength alloy in offshore- and onshore oil drilling exploration. In spite of already excellent mechanical properties, mechanical enhancement methods such as swaging, deep rolling (ball burnishing), shot peening or laser peening remain attractive for enhancing mechanical properties, especially under fatigue conditions. In the following contribution the effects of swaging, shot peening, deep rolling and laser peening on the high cycle fatigue strength of CuMn20Ni20 were investigated. The present study suggests that these treatments can further increase the fatigue strength and hardness of CuMn20Ni20. The contributing strengthening mechanisms are discussed through applying Electron Channeling Contrast Imaging (ECCI) and electron backscatter diffraction (EBSD) in scanning electron microscopy.