Researches regarding the properties of sintered electrical contacts obtained from mechanically alloyed W-Cu powders

摘要

In this paper are presented the experimental results regarding the elaboration of electrical contacts using W-Cu composite powders obtained by mechanical alloying (MA) process. For this research, commercial powders with a particle size between [10-80] μm were used. Three types of mixtures with different concentrations as follows: 90W-10Cu; 80W-20Cu; 70W-30Cu were mechanically alloyed for 2 up to 6 hours, using a planetary ball mill. The mixtures obtained after MA process were pressed in a cylindrical die at 400 respective 600 MPa. The evolution of green densities according to the compaction pressure and Cu content was studied. The green billets were sintered in an electrical furnace at 1180 °C and maintained 60 minutes at the sintering temperature in argon atmosphere. The evolution of densities, microstructures and electrical properties of the sintered samples function of the Cu content and compaction pressure were studied.