Diamond-cBN alloy: A universal cutting material

Abstract

Diamond and cubic boron nitride (cBN) as conventional superhard materials have found widespread industrial applications, but both have inherent limitations. Diamond is not suitable for high-speed cutting of ferrous materials due to its poor chemical inertness, while cBN is only about half as hard as diamond. Because of their affinity in structural lattices and covalent bonding character, diamond and cBN could form alloys that can potentially fill the performance gap. However, the idea has never been demonstrated because samples obtained in the previous studies were too small to be tested for their practical performance. Here, we report the synthesis and characterization of transparent bulk diamond-cBN alloy compacts whose diameters (3 mm) are sufficiently large for them to be processed into cutting tools. The testing results show that the diamond-cBN alloy has superior chemical inertness over polycrystalline diamond and higher hardness than single crystal cBN. High-speed cutting tests on hardened steel and granite suggest that diamond-cBN alloy is indeed a universal cutting material.

Elastic, magnetic and electronic properties of iridium phosphide Ir2P

“…Ir 2 P was synthesized using a mixture of Ir powder (purity 99.9%) and red phosphorus powder (purity 99.999%) with a molar ratio of Ir : P = 2 : 1 under high pressure/temperature conditions. The syntheses were carried out in a two-stage multi-anvil apparatus based on a DS 6 × 8 MN cubic press 41 42 and a Walker-type multianvil press at Arizona State University 43 . The 14/8 sample assembly, consisting of a 14 mm (edge length) MgO octahedron, a ZrO 2 thermal insulator and a Ta heater, was compressed by eight cubic WC anvils, each with 8-mm corner truncation (edge-length).…”

Pressure-induced structural and electronic transitions, metallization, and enhanced visible-light responsiveness in layered rhenium disulphide

“…Structure refinements were performed using Pawley method [35]. High-pressure electrical resistance (ER) was measured using a quasi-four-probe resistance measurement system consisting of a Keithley 6221 current source, a 2182A nanovoltmeter and 7001 voltage/current switch system in a DAC and a cubic large-volume press (LVP) [36][37][38]. Photocurrent measurements of powder and single-crystal samples were performed using an Autolab PGSTAT128N workstation to keep track of the current-time (I-t) data [38].…”

Atomic structure, electronic properties and generalized stacking fault energy of diamond/c-BN multilayer

“…Huang et al 15 applied molecular dynamics simulations for the responses of c-BN lms under nanoindentation, and found that during the indentation, plastic deformation of c-BN is can mainly be attributed to stress-induced slips of dislocations along {111}<110> orientations. In addition, Wang et al 16 reported the synthesis and characterization of transparent bulk diamond/c-BN alloy, and showed that the alloy has a superior chemical inertness over the polycrystalline diamond and a higher hardness than a single crystal.…”