Mechanical and tribological properties of Al-40Zn-Cu alloys


ALEMDAĞ Y. , Savaskan T.

TRIBOLOGY INTERNATIONAL, vol.42, no.1, pp.176-182, 2009 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 42 Issue: 1
  • Publication Date: 2009
  • Doi Number: 10.1016/j.triboint.2008.04.008
  • Title of Journal : TRIBOLOGY INTERNATIONAL
  • Page Numbers: pp.176-182

Abstract

One binary Al-40Zn and five ternary Al-40Zn-Cu alloys with different copper contents were prepared by permanent mould casting. Their microstructure and mechanical properties were investigated in as cast state. Friction and wear properties of the ternary alloys were studied using a conforming block-ondisc type tester. The results obtained were compared with those of SAE 65 bearing bronze. The microstructure of Al-40Zn-Cu alloys consisted of aluminium-rich alpha dendrites surrounded by eutectoid alpha+eta phases and theta(CuAl2) particles. Hardness of the ternary alloys increased continuously with increasing copper content, but their tensile strength decreased above 3% Cu. Friction coefficient and temperature of the Al-40Zn-Cu alloys and bronze increased in the initial period of run. This was followed by a reduction in the properties and attainment of constant levels afterwards. However, volume loss of the alloys increased rapidly at the beginning of the test run and reached almost constant levels after a sliding distance of approximately 400 km. The Al-40Zn-Cu alloys were found to be much superior to the SAE 65 bronze, as far as their wear resistance is concerned. Among the alloys tested, highest strength and wear resistance were obtained with the Al-40Zn-3Cu alloy. (C) 2008 Elsevier Ltd. All rights reserved.