Investigation on the Unlubricated Sliding Tribological Properties of Ti–20Zr–6.5Al–4V Alloy at Elevated Temperatures

Investigation on the Unlubricated Sliding Tribological Properties of Ti–20Zr–6.5Al–4V Alloy at Elevated Temperatures

In this study, unlubricated sliding friction and wear properties of a recently-developed TiZr-based alloy (Ti–20Zr–6.5Al–4V, TZ20 hereafter) were tested at elevated temperatures ranging from room temperature to 673 K. After the tribologicaltests, worn surface and cross-section of TZ20 alloy were analyzed to illustrate its wear behavior. The results showed that thewear rate was increased firstly with the ambient temperature, which then decreased when the temperature exceeded criticaltransition temperature (473 K). Also, the dominant wear mechanisms changed from adhesive wear at room temperature toabrasive wear at 473 K, and then to mild abrasive wear at highest ambient temperature of 673 K. The variations of wearbehaviors could be attributed to tribo-oxide layer formed during sliding process. At ambient temperature of 673 K, the tribooxidelayer formed on the surface was thicker and more compact, and showed more obvious protective role on tribologicalproperties of TZ20 alloy.

In this study, unlubricated sliding friction and wear properties of a recently-developed TiZr-based alloy (Ti–20Zr–6.5Al–4V, TZ20 hereafter) were tested at elevated temperatures ranging from room temperature to 673 K. After the tribologicaltests, worn surface and cross-section of TZ20 alloy were analyzed to illustrate its wear behavior. The results showed that thewear rate was increased firstly with the ambient temperature, which then decreased when the temperature exceeded criticaltransition temperature (473 K). Also, the dominant wear mechanisms changed from adhesive wear at room temperature toabrasive wear at 473 K, and then to mild abrasive wear at highest ambient temperature of 673 K. The variations of wearbehaviors could be attributed to tribo-oxide layer formed during sliding process. At ambient temperature of 673 K, the tribooxidelayer formed on the surface was thicker and more compact, and showed more obvious protective role on tribologicalproperties of TZ20 alloy.