Effects of TiC content and melt phase on microstructure and mechanical properties of ternary TiB2-based ceramic cutting tool materials

Effects of HfB2 and HfN Additions on the Microstructures and Mechanical Properties of TiB2-Based Ceramic Tool Materials

“…The fracture toughness ( K IC ) was measured via the direct indentation method and was calculated through the following equation [12,27]:$K_{IC}=0.203H_V{a}^{1/2}{false(\frac{c}{a}false)}^{-3/2}$ where H V is the Vickers hardness, 2 a is the length of the impression diagonal, and 2 c is the overall indentation crack length including 2 a . The indenter (HVS-30, Shanghai Precision Instruments Co., Ltd., Shanghai, China) was of Vickers DPH (diamond pyramid hardness) type and the applied static load was 196 N for 15 s. Vickers hardness was measured on the polished surfaces using a diamond pyramid indenter under a load of 196 N by an HV-120 based on Chinese National Standards GB/T 16534-2009 [28].…”

“…Usually, the hard phases included TaC, TiSi 2 , Al 2 O 3 , WC, TiC, B 4 C, NbC, MoSi 2 , SiC, and ZrB 2 [9,10,11,12,13,14,15,16], which could inhibit the grain growth of the base material to obtain a fine microstructure. HfB 2 and HfN have high hardness, high melting point, and high oxidation resistance, and as reinforcements they can enhance the mechanical properties of ceramics such as ZrB 2 -CrSi 2 -HfB 2 , ZrB 2 -SiC-HfB 2 , B 4 C-HfB 2 , and SiBCN-HfN [17,18,19,20], which make them potential candidate reinforcements for ceramic tool materials.…”

“…In addition, because HfB 2 and HfN have better thermal stability to resist deformation and decomposition at elevated temperature, they may improve the cutting performance and working life of TiB 2 -based ceramic tools. The metal phases often contain Fe, Co, Ni, and Mo [7,12,21,22], which could decrease the sintering temperature and improve the boundary strength among grains and relative density, while the ceramic whiskers such as aluminum borate whiskers and SiC whiskers could change the direction of crack growth to consume more crack propagation energy [23,24,25], which could improve the flexural strength and fracture toughness. Usually, adopting a combination of reinforcements for fabricating TiB 2 -based ceramics can obtain better mechanical properties.…”

Effect of Ni content on microstructures and mechanical properties of hot-pressed TiC–TiB2–Ni composite

“…Both TiC and TiB 2 possess high melting point and hardness, good electroconductivity and thermal conductivity, excellent chemical and thermal stability as well as low thermal expansivity [1][2][3][4][5]. Compared to TiC or TiB 2 single phase ceramics, TiC-TiB 2 composite ceramics not only combine both the characteristics of TiC and TiB 2 [6,7], but also show more excellent physical and mechanical properties [8,9].…”

Combustion Synthesis of TiB2-TiC/42CrMo4 Composites with Gradient Joint Prepared in Different High-Gravity Fields

“…Because of its high hardness, high corrosion resistance, high dynamic strength, and low density, TiB 2 -based or TiCbased ceramic materials attract a lot of attention as potential materials for engineering applications (Ref [1][2][3]. The novel TiB 2 -TiC ceramic possesses more advantages than traditional metals, especially in ceramic armor or high-temperature techniques (Ref 2).…”