Hard and tough ultrafine-grained B4C-cBN composites prepared by high-pressure sintering

Because of the extremely rigid lattice structure of diamond, generating new dislocations or moving existing dislocations in diamond by applying mechanical stress at ambient temperature is very difficult. Analysis of portions of diamonds deformed under bending stress at elevated temperature has shown that diamond deforms plastically under suitable conditions and that its primary slip systems are on the ﹛111﹜ planes. Plastic deformation in diamond is more commonly observed during the high temperature - high pressure sintering process used to make diamond compacts. The pressure and temperature conditions in the sintering presses are sufficiently high that many diamond grains in the sintered compact show deformed microtructures.In this report commercially available polycrystalline diamond discs for rock cutting applications were analyzed to study the deformation substructures in the diamond grains using transmission electron microscopy. An individual diamond particle can be plastically deformed in a high pressure apparatus at high temperature, but it is nearly impossible to prepare such a particle for TEM observation, since any medium in which the diamond is mounted wears away faster than the diamond during ion milling and the diamond is lost.

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Microstructural, mechanical and tribological properties of ultrafine-grained Cu–Cr–Zr alloy processed by high pressure torsion

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2019.152675 ◽

2020 ◽

Vol 816 ◽

pp. 152675 ◽

Cited By ~ 8

Author(s):

G. Purcek ◽

H. Yanar ◽

M. Demirtas ◽

D.V. Shangina ◽

N.R. Bochvar ◽

...

Keyword(s):

High Pressure ◽

Tribological Properties ◽

High Pressure Torsion ◽

Mechanical And Tribological Properties ◽

Ultrafine Grained ◽

Zr Alloy

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Foam glass obtained through high‐pressure sintering

Journal of the American Ceramic Society ◽

10.1111/jace.15574 ◽

2018 ◽

Vol 101 (9) ◽

pp. 3917-3923 ◽

Cited By ~ 10

Author(s):

Martin B. Østergaard ◽

Rasmus R. Petersen ◽

Jakob König ◽

Michal Bockowski ◽

Yuanzheng Yue

Keyword(s):

High Pressure ◽

Foam Glass ◽

High Pressure Sintering

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Percolating porosity in ultrafine grained copper processed by High Pressure Torsion

Journal of Applied Physics ◽

10.1063/1.4829705 ◽

2013 ◽

Vol 114 (18) ◽

pp. 183509 ◽

Cited By ~ 11

Author(s):

Matthias Wegner ◽

Jörn Leuthold ◽

Martin Peterlechner ◽

Daria Setman ◽

Michael Zehetbauer ◽

...

Keyword(s):

High Pressure ◽

High Pressure Torsion ◽

Ultrafine Grained

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Highly Dense Amorphous Si2 BC3 N Monoliths with Excellent Mechanical Properties Prepared by High Pressure Sintering

Journal of the American Ceramic Society ◽

10.1111/jace.13802 ◽

2015 ◽

Vol 98 (12) ◽

pp. 3782-3787 ◽

Cited By ~ 14

Author(s):

Bin Liang ◽

Zhihua Yang ◽

Jiancun Rao ◽

Delong Cai ◽

Xiaoming Duan ◽

...

Keyword(s):

Mechanical Properties ◽

High Pressure ◽

High Pressure Sintering

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The Processing of Ultrafine-Grained Materials Using High-Pressure Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.558-559.1283 ◽

2007 ◽

Vol 558-559 ◽

pp. 1283-1294 ◽

Cited By ~ 1

Author(s):

Cheng Xu ◽

Z. Horita ◽

Terence G. Langdon

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

High Pressure ◽

High Pressure Torsion ◽

Metallic Materials ◽

Grain Sizes ◽

Ultrafine Grained ◽

Wide Range ◽

Ultrafine Grained Materials ◽

Thin Disks

It is now well-established that processing through the application of severe plastic deformation (SPD) leads to a significant reduction in the grain size of a wide range of metallic materials. This paper examines the fabrication of ultrafine-grained materials using high-pressure torsion (HPT) where this process is attractive because it leads to exceptional grain refinement with grain sizes that often lie in the nanometer or submicrometer ranges. Two aspects of HPT are examined. First, processing by HPT is usually confined to samples in the form of very thin disks but recent experiments demonstrate the potential for extending HPT also to bulk samples. Second, since the strains imposed in HPT vary with the distance from the center of the disk, it is important to examine the development of inhomogeneities in disk samples processed by HPT.

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