Mechanical, Wear and Thermal Behaviors of Graphene Reinforced Titanium Composites

High temperature tribological response of Fe-2Cu-0.8C-CaF2 self-lubricating composites at high speeds

“…C3 showed least surface damage due to highest hardness and lowest porosity amongst composites. Figure 7 shows a schematic of oxidation and delamination in composites during sliding: (a) Composite has interconnected subsurface pores, (b) entry of air into pin bulk through subsurface pores, i.e., diffusion of oxygen via interconnected pores and through cracks in delaminated regions causes oxidation in bulk material 11,27,28 and (c) cracks nucleate at subsurface pores and propagate causing delamination. Wear debris generated during the sliding of C9 at 5 and 10 m/s are shown in Figure 8.…”

“…Unlike in liquid lubrication, wherein heat is conducted away from sliding interface by lubricant medium, in solid-lubrication, much of the heat generated remains localized. As a result, temperature rise in self-lubricating materials causes (i) thermal softening of metallic matrices, [6][7][8][9] (ii) oxidation of matrix in iron-based materials, [6][7][8][9] (iii) tribochemical reactions i.e., formation of new phases, e.g., CaMoO 4 high temperature lubricant in Fe-Mo-CaF 2 composites slid at 600 °C which reduced friction 10 and iron tungstate (Fe 7 W 6 ) hard phase in Fe-W-CaF 2 composites which reduced wear 11 and (iv) effective/ineffective lubrication. Better thermal conductivity and thermal diffusivity of materials subjected to sliding promotes better heat dissipation and therefore alters the above factors, thereby changing the tribological response of the materials.…”

“…17 Oxidation temperature of a solid lubricant is the upper limit, below which its lubrication ability can be effectively utilized, e.g., 350 °C for MoS 2 , 450 °C for graphite, 600 °C for WS 2 , in the range 500-1100 °C for CaF 2 . [1][2][3][4][5]11 Self-lubricating composites have promising potential to meet the demands of global initiatives for green manufacturing and sustainability. 18 Increased attention is being given to solid lubrication as could be seen from the growing number of papers and reviews in the field in recent years.…”

Incorporation of graphene nano platelets in suspension plasma sprayed alumina coatings for improved tribological properties

“…Nonetheless, the excellent mechanical and lubricating properties of graphene are particularly ideal for it to be exploited to develop wearresistant coatings for durable engineering components [16,17]. So far, graphene has been utilized as a reinforcement in different systems (metals, polymers and ceramics) to enhance their mechanical and wear properties [18,19,20].…”

Effect of Ti3SiC2 Amount on Microstructure and Properties of TiAl Matrix Composites

“…The friction test was performed at room temperature and 550°C under a 300 N load and at a 0.261 m/s gliding speed for 10 min. The friction coe cient was automatically recorded by the computer system of the friction tester, while the wear rate was calculated using wear volumes described as [19]: where V (mm 3 ) is the wear volume obtained by measuring the weight loss in a microbalance after ultrasonic cleaning and drying and the measured density, P (N) is the applied load, and L (m) is the total sliding distance.…”