High‐entropy carbide‐based ceramic cutting tools

Abstract

In this study, a novel high-entropy carbide-based ceramic cutting tool was developed. The cutting performance of three kinds of high-entropy carbide-based ceramic tools with different mechanical properties for the ISO C45E4 steel were evaluated. Although the pure (Ti 0.2 Zr 0.2 Nb 0.2 Ta 0.2 Mo 0.2 )C 0.8 ceramic cutting tool exhibited the highest hardness of 25.06 ± 0.32 GPa, the cutting performance was poor due to the chipping and catastrophic failure caused by the low toughness (2.25 ± 0.27 MPa m 1/2 ). The (Ti 0.2 Zr 0.2 Nb 0.2 Ta 0.2 Mo 0.2 )C 0.8 -15 vol% cobalt cutting tool with highest fracture toughness (6.37 ± 0.24 MPa m 1/2 ) and lowest hardness (17.29 ± 0.79 GPa) showed the medium cutting performance due to the low wear resistance caused by the low hardness. The (Ti 0.2 Zr 0.2 Nb 0.2 Ta 0.2 Mo 0.2 )C 0.8 -7.7 vol% cobalt cutting tool showed the longest effective cutting life of ∼67 min due to the high wear resistance and chipping resistance caused by the high hardness (21.05 ± 0.72 GPa), high toughness (5.35 ± 0.51 MPa m 1/2 ), and fine grain size (0.60 ± 0.15 µm). The wear mechanisms of the cobalt-containing (Ti 0.2 Zr 0.2 Nb 0.2 Ta 0.2 Mo 0.2 )C 0.8 ceramic cutting tools included adhesive wear and abrasive wear and oxidative wear. This research indicated that the high-entropy carbide-based ceramics with high hardness and high toughness have potential use in the field of cutting tool application.

High‐temperature self‐lubricating properties of single‐phase high‐entropy carbides under a vacuum environment

“…Sintering pressure and holding time were 40 MPa and 10 min, respectively. The hardness was measured using a HTV-PHS30 Vickers microhardness tester under a load of 5 kg with a hold time of 10 s. The tribological properties were characterized by a rotational tribometer (GHT-1000E, China) under a vacuum environment (5)(6)(7). The tribo-pairs were Al 2 O 3 balls with a diameter of 6.3 mm.…”

“…To date, broad endeavors have been committed to investigating an assortment of high‐entropy ceramics, including carbides, borides, nitrides, oxides, silicides, and sulfides, which exhibits a wide range of applications 3,4 . Among them, high‐entropy carbides have stimulated concentrated research because of the high hardness and strength, good thermal stability, and various potential applications 5–7 …”

“…3,4 Among them, high-entropy carbides have stimulated concentrated research because of the high hardness and strength, good thermal stability, and various potential applications. [5][6][7] present, the densification is mainly enhanced by reducing the particle size of the raw powders ascribed to finer particles with a higher surface energy, thus providing a higher driving force at lower temperatures. 14,15 The nanocrystalline high-entropy carbides were fabricated by sintering the (Hf 0.25 Zr 0.25 Ta 0.25 Ti 0.25 )C nano-powders, which exhibited the excellent mechanical properties (Vickers hardness: 25.7 GPa, fracture toughness: 4.3 MPa m 1/2 ).…”

Rational design of moldable calcium chloride ceramic‐like material with supramolecular structure

“…[2][3][4] Often ceramic materials can be used not only for construction, tools, and biomedicine, but also as functional materials with optical, thermal, and electrical properties. [5][6][7] However, the manufacture of inorganic ceramic materials prepared with inorganic salts such as sodium silicate, calcium carbonate, calcium chloride, etc., is limited by crystallization, 8 which frequently produces powders 9 rather than monoliths with continuous structures like polymer materials. Conventionally, ceramic materials are produced at very high temperatures and under high pressures; the processes are complex and can result in high costs of the products.…”

“…Ceramic materials are usually prepared from a variety of inorganic compounds such as silicates, alumina, and titanium dioxide 2–4 . Often ceramic materials can be used not only for construction, tools, and biomedicine, but also as functional materials with optical, thermal, and electrical properties 5–7 . However, the manufacture of inorganic ceramic materials prepared with inorganic salts such as sodium silicate, calcium carbonate, calcium chloride, etc., is limited by crystallization, 8 which frequently produces powders 9 rather than monoliths with continuous structures like polymer materials.…”