Microstructure and Mechanical Properties of High Strength Brass Alloy with Some Elements

Abstract

The purpose of this research is the development of a high strength α-β brass (Cu-40 Zn) with additions of elements of small solid solubility in brass. Cu-40 Zn with 0.6mass% Tin (Sn) and various contents of Chromium (Cr) and Iron (Fe) were prepared by casting (Cu-40 Zn-CrFeSn). The yield strength (YS) and ultimate tensile strength (UTS) of cast Cu-40 Zn-CrFeSn has 190MPa and 400MPa. Furthermore, the YS and UTS of extruded Cu-40 Zn-CrFeSn was 300MPa and 600MPa, 23% and 36% higher than that of extruded binary Cu-40 Zn alloy. Vickers micro hardness of 158Hv was higher than that of extruded Cu-40 Zn alloy (131Hv). In addition, the elongation of extruded Cu-40 Zn-CrFeSn was 35%. The strengthening mechanisms of these alloys were considered as follows; one was a solid solution strengthening of Cr, Fe and Sn additives which were identified by TEM-EDS and SEM-EDS. The other was increasing of the area ratio of β-phase in Cu-40 Zn-CrFeSn, compared to that of Cu-40 Zn.