*Article* **Microstructure and Tribological Properties of Spark-Plasma-Sintered Ti3SiC2-Pb-Ag Composites at Elevated Temperatures**

**Rui Zhang 1,2,3,4,\*, Huiming Zhang <sup>1</sup> and Fuyan Liu 5,\***

	- 3 Institute for Advanced Materials Deformation and Damage from Multi-Scale, Chengdu University, Chengdu 610106, China
	- <sup>4</sup> School of Mechanical Engineering, Xinjiang University, Urumqi 830000, China
	- <sup>5</sup> School of Chemical Engineering and Materials, Changzhou Institute of Technology, Changzhou 213032, China

**Abstract:** Ti3SiC<sup>2</sup> -PbO-Ag composites (TSC-PA) were successfully prepared using the spark plasma sintering (SPS) technique. The ingredient and morphology of the as-synthesized composites were elaborately investigated. The tribological properties of the TSC-PA pin sliding against Inconel 718 alloys disk at room temperature (RT) to 800 ◦C were examined in air. The wear mechanisms were argued elaborately. The results showed that the TSC-PA was mainly composed of Ti3SiC<sup>2</sup> , Pb, and Ag. The average friction coefficient of TSC-PA gradually decreased from 0.72 (RT) to 0.3 (800 ◦C), with the temperature increasing from RT to 800 ◦C. The wear rate of TSC-PA showed a decreasing trend, with the temperature rising from RT to 800 ◦C. The wear rate of Inconel 718 exhibited positive wear at RT and negative wear at elevated temperatures. The tribological property of TSC-PA was related to the tribo-chemistry, and the abrasive and adhesive wear.

**Keywords:** Ti3SiC<sup>2</sup> -PbO-Ag composites; tribo-chemical reaction; self-lubricating composite; tribooxidation
