Microstructure and Mechanical Properties of ZrB2–HfC Ceramics Influenced by HfC Addition

Abstract

ZrB2–HfC ceramics have been fabricated using the liquid phase sintering technique at a sintering temperature as low as 1750 °C through the addition of Ni. The effects of HfC addition on the microstructure and mechanical properties of ZrB2–based ceramics have been investigated. These ceramics were composed of ZrB2, HfC, Ni, and a small amount of possible (Zr, Hf)B2 solid solution. Small HfC grains were distributed among ZrB2 grain boundaries. These small grains could improve the density of ZrB2–based ceramics and play a pinning role. With HfC content increasing from 10 wt % to 30 wt %, more HfC grains were distributed among ZrB2 grain boundaries, leading to weaker interface bonding among HfC grains; the relative density and Vickers hardness increased, and flexural strength and fracture toughness decreased. The weak interface bonding for 20 and 30 wt % HfC contents was the main cause of the decrease in both flexural strength and fracture toughness.

Processing of dense bioinspired ceramics with deliberate microstructure

“…Using liquid phase sintering by the addition of other dopants like silica, calcium, magnesium, or titanium could further vary the grain sizes, aspect ratios and final densities . Furthermore, doping atoms segregated at the interface could influence the interfacial strength and, therefore, the mechanical properties of the sintered ceramics, as reported in other systems …”

“…15 Furthermore, doping atoms segregated at the interface could influence the interfacial strength and, therefore, the mechanical properties of the sintered ceramics, as reported in other systems. 31,32 Using this bottom-up approach based on MASC and TGG, we could produce dense alumina ceramics with a texture directly resulting from the magnetic alignment of the templates. Since no pressing was required for the densification, it was possible to exploit the full potential of magnetic manipulation: its ability to orient anisotropic platelets at along any direction in space.…”

Tribological behaviors of HfC coating prepared on 45 steel via double glow plasma surface metallurgy technique

“…To solve the wear failure of the substrate surface, the materials with high hardness and good friction reduction should be chosen to prepare wear-resistant coatings (Yu et al , 2009; Yue et al , 2007; Yigit et al , 2008). Hafnium carbide (HfC) is a kind of ceramic with high hardness and high elastic modulus and thus it is often used as an additive to improve the friction performance of the cutting tools (Jing et a l., 2018; Jinpeng et al , 2020). There are many methods that have successfully prepared HfC coatings, such as low pressure chemical vapor deposition (Xiong et al , 2013), supersonic atmospheric plasma spraying (Yang et al , 2017), reactive melt infiltration (Ye et al , 2013) and reactive magnetron sputtering (Mohammad et al , 2007).…”

Spectral and electrical properties of 3 MeV and 10 MeV proton irradiated InGaAsP single junction solar cell

“…9,10) Radiation effects of GaAs-based solar cells have been studied widely in order to extend their lifetime in space missions. [11][12][13][14] However, there are fewer reports on the radiation effects of wafer bonded four-junction solar cells compared to that of conventional LM cells. In our previous electron irradiation study on GaInP/GaAs//InGaAsP/InGaAs wafer bounded four-junction solar cell 15) and its subcells, 16) the result showed the changes in electrical and optical properties of its InGaAsP and InGaAs subcells are the main reason for the degradation of the overall cell performance.…”