Effect of TiB₂ content on the microstructure and mechanical properties of Ti(C,N)–TiB₂–FeCoCrNiAl high-entropy alloys composite cermets

Abstract

Composite cermets with different mass ratios of Ti (C,N)/TiB 2 and 10 wt % FeCoCrNiAl high-entropy alloys (HEAs) binder were fabricated by mechanical alloying and vacuum hot press sintering. The effect of the TiB 2 content on the microstructure and mechanical properties of the Ti (C,N)TiB 2 HEAs cermets was systematically examined and is discussed in detail. The microstructure was analyzed by X-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy (TEM). The results of this study show that a small amount of Fe 2 B phase was detected in the XRD patterns besides the Ti(C,N) and TiB 2 phase. The TEM observation shows the presence of a HEAs binder phase, which was tightly bound to Ti(C,N) and TiB 2 phases. The grain size of the composite cermets gradually decreased with increasing TiB 2 content increased from 0 to 45 wt %. The relative density of the composite cermets first increased and then decreased with increasing TiB 2 content from 11.25 to 45 wt %. When the TiB 2 content reached 22.5 wt %, the composite cermets exhibited excellent comprehensive performance. The grain size, relative density, and hard phase of the composite cermets were the dominating factors that determined the mechanical properties with increasing TiB 2 content. The relative density, Vickers hardness, bending strength, and fracture toughness of the Ti (C,N)22.5 wt % TiB 2 10 wt % HEAs composite cermets reached 98.

Effect of high-entropy alloy binder content on the microstructure, mechanical properties and oxidation behavior of Ti(C,N)–TiB₂ cermets

“…The small amount of black contrast distributed between them indicates pores or Al 2 O 3 , which has been proven in previous research. 25) It can be seen in Fig. 2 that as the HEA content increases, the black contrast pores gradually decrease, and the density of the composite cermets gradually increases.…”

“…12),22)24) However, studies on HEA binder content affecting the performance of Ti(C,N)based cermets are still lacking. Therefore, as a continuation of the previous research, 25) this study investigates the effect of AlCoCrFeNi HEA binder content on the microstructure, mechanical properties and high-temperature oxidation behavior of Ti(C,N)-based cermets.…”

Application of Adaptive Materials and Coatings to Increase Cutting Tool Performance: Efficiency in the Case of Composite Powder High Speed Steel

“…An analysis of the latest progressive research results shows that the use of highentropy alloys (HEAs) in their manufacture has attracted the most significant interest in creating tool materials with a self-healing effect today [68][69][70]. In particular, HEAs based on Fe-Co-Cr-Ni-Al and Co-Cr-Fe-Ni-Ti-Al are already effectively used as binders (mass fraction up to 20%) in the production of TiCN-TiB 2 composite cermets by vacuum hot pressing.…”