Researchers combine diamond and cubic boron nitride with a novel alloying process for a superhard material
Diamonds are forever, except when they oxidize while cutting through iron, cobalt, nickel, chromium, or vanadium at high temperatures. Conversely, cubic boron nitride possesses superior chemical inertness but only about half of the hardness of diamonds.
In an attempt to create a superhard material better suited for a wide variety of materials on an industrial scale, researchers at Sichuan University in Chengdu, China, have created an alloy composed of diamonds and cubic boron nitride (cBN) that boasts the benefits of both.
"Diamond and cubic boron nitride could readily form alloys that can potentially fill the performance gap because of their affinity in structure lattices and covalent bonding character," said Duanwei He, a professor at Sichauan University's Institute of Atomic and Molecular Physics. "However, the idea has never been demonstrated because samples obtained in previous studies are too small to test their practical performance."
He and his colleagues at the University of Nevada and the Chinese Academy of Sciences detail their procedure this week in Applied Physics Letters, from AIP Publishing.
To synthesize diamond-cBN alloys, the researchers subjected a homogenous mixture of diamond and cubic boron nitride powder to a vacuum furnace at 1300 K for two hours, then pressed the material into 3.5 millimeter pellets under pressure greater than 15 gigapascals and temperatures above 2000 K. The pellets were then polished and sharpened into cutting implements.
The researchers tested the cutting performances of their alloy on hardened steel and granite bars on a computer numerical controlled lathe. They found that the diamond-cBN alloy rivaled polycrystalline cubic boron nitride's wear and tool life on the steel samples, and exhibited significantly less wear when cutting through granite. The alloy also demonstrated a more preferable high-speed cutting performance than either polycrystalline CBN or commercial polycrystalline diamonds.
Future work for He and his colleagues involves developing synthesis technology for centimeter-sized diamond-cBN alloy bulks to bring the process up to industrial-scale production.
The article, "Diamond-cBN Alloy: a Universal Cutting Method” is authored by Pei Wang, Duanwei He, Liping Wang, Zili Kou, Yong Li, Lun Xiong, Qiwei Hu, Chao Xu, Li Lei, Qiming Wang, Jing Liu, and Yusheng Zhao. It will appear in the journal Applied Physics Letters on September 8, 2015 (DOI: 10.1063/1.4929728). After that date, it can be accessed at: http://scitation.aip.org/content/aip/journal/apl/107/10/10.1063/1.4929728
ABOUT THE JOURNAL
Applied Physics Letters features concise, rapid reports on significant new findings in applied physics. The journal covers new experimental and theoretical research on applications of physics phenomena related to all branches of science, engineering, and modern technology.
Jason Socrates Bardi
Jason Socrates Bardi | newswise
Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says
19.07.2018 | Purdue University
Machine-learning predicted a superhard and high-energy-density tungsten nitride
18.07.2018 | Science China Press
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
19.07.2018 | Earth Sciences
19.07.2018 | Power and Electrical Engineering
19.07.2018 | Materials Sciences