Rapid Synthesis of W–Cr Solid–Solution by Dielectric-Barrier Discharge-Plasma-Assisted Ball Milling

Abstract Supersaturated solid–solutions in a W–Cr alloy system were fabricated by conventional milling and plasma milling. The different extension mechanisms of the solid solubility that were created by ball milling with and without discharge plasma were studied. The solid–solubility of Cr in W for the P-milling W–Cr alloy system was higher, which indicates that plasma milling promotes the formation of W(Cr) solid–solution more easily than conventional milling. According to Miedema’s model, in the W–Cr alloy system, the free-energy change to form a W(Cr) solid solution by plasma milling is reduced compared with conventional milling because of the heating effect of the discharge plasma. Therefore, a higher stored energy in the grain boundaries and dislocations of the W–Cr nanograins during plasma milling makes it easier to overcome the thermodynamic barrier in the formation of a solid–solution, when compared with conventional milling. Graphic Abstract