Enhancement of electrical and thermal conductivity of low-cost novel Cu–Ag alloys prepared by hot-pressing and electroless plating from recycled electrolytic copper powders

Abstract

In this study, electrolytic copper powders (ECs) were fabricated by electrolysis method using scrap copper pieces as the main material. Copper-silver bimetallic powders (ESCs) were obtained by electroless silver coating process. Then, copper-silver layered materials (ESC materials) with different process parameters were fabricated by using the hot-pressing method. The effects of hot-pressing temperature (25, 200, 400, 500 and 550 °C) and pressures (400, 500 and 600 MPa) on the properties of ESC materials were investigated. Morpholological examination of ECs and ESCs and microstructure examination of layered copper-silver materials was performed using scanning electron microscopy (SEM). Electrical and thermal conductivity, hardness and density of the materials produced with different hot-pressing parameters were examined. According to the results, it was determined that materials with the best physical and mechanical properties were obtained when the temperature used in hot- pressing was 500 °C and the pressure was 600 MPa. In materials produced at higher temperatures and pressures, a decrease in electrical and thermal conductivity values was determined as a result of the increase in deformation.