Effect of Magnesium Content on Machinability of Cu-Zn-Bi-Sb Alloy

Abstract:

In order to develop high-performance lead-free brasses, the effect of magnesium content on the machinability of lead-free brass alloys was carefully studied in the present work. The ingots of the Cu-Zn-Bi-Sb alloy were fabricated in terms of different magnesium contents of 1.0, 2.0, 3.0 and 4.0 wt%. The difference in the machinability of the Cu-Zn-Bi-Sb alloy ingots was discussed in terms of their microstructure, mechanical properties and chip morphologies. X-ray diffraction analysis indicated that α phase (0~38 Zn by atom %), β phase (45~49 Zn by atom %), CuMgSb and CuMgZn existed in the Cu-Zn-Bi-Sb alloys with the different magnesium contents. With increasing the content of magnesium, the machinability of the present lead-free brass alloys was markedly improved, which is mainly attributed to the formation of intermetallic compounds such as CuMgSb and CuMgZn.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 544-548
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.544
• Online since: March 2016
• Authors: Chun Lei Gan*, Kaihong Zheng, Hai Yan Wang, Nan Zhou
• Keywords: Lead-Free Machinable Brass, Machinability, Magnesium Content

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