The influence of aging treatment on the microstructure,mechanical properties and electrical conductivity of Cu-0.5 wt pct Be alloy for connector material applications was investigated.The properties of mechanical stre...The influence of aging treatment on the microstructure,mechanical properties and electrical conductivity of Cu-0.5 wt pct Be alloy for connector material applications was investigated.The properties of mechanical strength and electrical conductivity increase with increasing aging temperature and time.Microstructure of the aged Cu-Be alloy revealed that grain size and fraction of low angle and high angle grain boundary were not greatly changed;however,transmission electron microscopy （TEM） analysis exhibited that beryllides precipitation （CoBe and NiBe） with a size of 50 nm were distributed in grains.It was,therefore concluded that these beryllide precipitates improved the mechanical strength and also it was favor in improvement of electrical conductivity.展开更多
Mechanical properties and fracture behavior of Cu-0.84Co 0.23Be alloy after plastic deformation and heat treatment were comparatively investigated. Severe plastic deformation by hot extrusion and cold drawing was adop...Mechanical properties and fracture behavior of Cu-0.84Co 0.23Be alloy after plastic deformation and heat treatment were comparatively investigated. Severe plastic deformation by hot extrusion and cold drawing was adopted to induce large plastic strain of Cu 0.84Co-0.23Be alloy. The tensile strength and elongation are up to 476.6 MPa and 18%, respectively. The fractured surface consists of deep dimples and micro voids. Due to the formation of su- persaturated solid solution on the Cu matrix by solution treatment at 950℃ for 1 h, the tensile strength decreased to 271.9 MPa, while the elongation increased to 42%. The fracture morphology is parabolic dimple. Furthermore, the tensile strength increased significantly to 580.2 MPa after aging at 480 ℃ for 4 h. During the aging process, a large number of precipitates formed and distributed on the Cu matrix. The fracture feature of aged specimens with low elongation （4.6%） exhibits an obvious brittle intergranular fracture. It is confirmed that the mechanical properties and fracture behavior are dominated by the microstrueture characteristics of Cu-0.84Co 0.23Be alloy after plastic de- formation and heat treatment. In addition, the fracture behavior at 450 ℃ of aged Cu-0.84Co 0.23Be alloy was also studied. The tensile strength and elongation are 383.6 MPa and 11.2%, respectively. The fractured morphologies are mainly candy-shaped with partial parabolic dimples and equiaxed dimples. The fracture mode is multi mixed mechanism that brittle intergranular fracture plays a dominant role and ductile fracture is secondary.展开更多
文摘The influence of aging treatment on the microstructure,mechanical properties and electrical conductivity of Cu-0.5 wt pct Be alloy for connector material applications was investigated.The properties of mechanical strength and electrical conductivity increase with increasing aging temperature and time.Microstructure of the aged Cu-Be alloy revealed that grain size and fraction of low angle and high angle grain boundary were not greatly changed;however,transmission electron microscopy （TEM） analysis exhibited that beryllides precipitation （CoBe and NiBe） with a size of 50 nm were distributed in grains.It was,therefore concluded that these beryllide precipitates improved the mechanical strength and also it was favor in improvement of electrical conductivity.
基金Sponsored by National Key Research and Development Program of China(2016YFB0301401)State Key Program of National Natural Science Foundation of China(U1502274)+1 种基金Innovation Scientists and Technicians Troop Construction Projects of Henan Province of China(C20150014)Program for Innovation Research Team(in Science and Technology)in University of Henan Province of China(14IRTSTHN007)
文摘Mechanical properties and fracture behavior of Cu-0.84Co 0.23Be alloy after plastic deformation and heat treatment were comparatively investigated. Severe plastic deformation by hot extrusion and cold drawing was adopted to induce large plastic strain of Cu 0.84Co-0.23Be alloy. The tensile strength and elongation are up to 476.6 MPa and 18%, respectively. The fractured surface consists of deep dimples and micro voids. Due to the formation of su- persaturated solid solution on the Cu matrix by solution treatment at 950℃ for 1 h, the tensile strength decreased to 271.9 MPa, while the elongation increased to 42%. The fracture morphology is parabolic dimple. Furthermore, the tensile strength increased significantly to 580.2 MPa after aging at 480 ℃ for 4 h. During the aging process, a large number of precipitates formed and distributed on the Cu matrix. The fracture feature of aged specimens with low elongation （4.6%） exhibits an obvious brittle intergranular fracture. It is confirmed that the mechanical properties and fracture behavior are dominated by the microstrueture characteristics of Cu-0.84Co 0.23Be alloy after plastic de- formation and heat treatment. In addition, the fracture behavior at 450 ℃ of aged Cu-0.84Co 0.23Be alloy was also studied. The tensile strength and elongation are 383.6 MPa and 11.2%, respectively. The fractured morphologies are mainly candy-shaped with partial parabolic dimples and equiaxed dimples. The fracture mode is multi mixed mechanism that brittle intergranular fracture plays a dominant role and ductile fracture is secondary.
