Volume 11, Issue 6, 2002

Ahn JJ and Ochiai S

International Innovation Center, Kyoto University, Sakyo, Kyoto, 606 – 8501, Japan, Tel:+81-75-753-5194, Fax;+81-75-753-4841, ahn@mech.kyoto-u.ac.jp

ABSTRACT

The effects of sliding speed and wear environment temperature (hereafter denoted as temperature) on the wear behaviour and friction coefficient of SiC particle reinforced Al6061 composites (SiCp/Al) were studied using wear and friction test of a ring on disc type, and difference of wear mechanism in terms of temperature was also examined by a microscopic observation of worn surfaces. Thin surface layer (TSL) formed on the worn surface during the experiment was enhanced with increase of temperature. However, such a TSL was cracked due to point contact between the counter material and coarse SiC particles (and/or SiC clusters) existing on the worn surface of the SiCp/Al. Contour of worn surfaces became rougher with increase of temperature and sliding speed. Wear mechanism of the AA6061 changed from abrasive wear into adhesive wear at 300°C while for the SiCp/Al, wear mechanism did not changed in the test conditions. That is, abrasive wear was maintained up to 300°C. Due to the presence of SiC particles, Friction coefficient of the SiCp/Al was larger than that of the AA6061 regardless of the temperature. However, scatter of friction coefficient against temperature was smaller in the SiCp/Al than in the AA6061. Furthermore, the weight loss, the difference of specimen weight before and after the experiment, under the severest test condition was less in the SiCp/Al than in the AA6061.

Keywords: SiCp/Al composites, wear and friction test, friction coefficient, abrasive and adhesive wears, thin surface layer