抄録
ABSTRACT
In this study, the effects of additive alloying elements on microstructure and mechanical properties of Cu – 40 % Zn alloy prepared by powder metallurgy (P/M) process were investigated. Raw Cu – 40Zn – Cr – Ti – Fe – Sn brass powders, having a single beta phase, were made by water-atomization process. Grain size of brass powder was smaller with increasing the solid solution of alloying elements. The brass alloy powder billet consolidated by sintering at less than 873 K had high solid solution of alloying elements. P/M Cu – 40Zn – 0.8Cr0.3Fe0.6Sn0.6Ti extruded material at 773 K showed 751 MPa UTS, 582 MPa YS and, 17.0 % elongation. SEM – EDS, XRD and TEM analysis clarified this P/M high strength brass alloy was mainly strengthened by solid solution mechanism of the alloying elements such as Cr and Ti which had a low solid solubility limit in brass. Extruded material of P/M Cu – 40Zn – 0.8Cr0.3Fe0.6Sn0.6Ti with 1.0 mass% graphite particles had both high strength and suitable machinability by solid solution of alloying elements due to no formation of hard carbides.
