A permanent magnet is expressed by a composition formula: R.sub.pFe.sub.qM.sub.rCu.sub.tCo.sub.100-p-q-r-t. The magnet comprises a metal structure including a main phase having a Th.sub.2Zn.sub.17 crystal phase and a grain boundary phase. The main phase includes a cell phase having the Th.sub.2Zn.sub.17 crystal phase and a Cu-rich phase. A section including a c-axis of the Th.sub.2Zn.sub.17 crystal phase has a first region in the crystal grain and a second region in the crystal grain, the first region is provided in the cell phase divided by the Cu-rich phase, the second region is provided within a range of not less than 50 nm nor more than 200 nm from the grain boundary phase in a direction perpendicular to an extension direction of the grain boundary phase, and a difference between a Cu concentration of the first region and a Cu concentration of the second region is 0.5 atomic percent or less.

A permanent magnet is expressed by a composition formula: R.sub.pFe.sub.qM.sub.rCu.sub.tCo.sub.100-p-q-r-t. The magnet comprises a metal structure including a main phase having a Th.sub.2Zn.sub.17 crystal phase and a grain boundary phase. The main phase includes a cell phase having the Th.sub.2Zn.sub.17 crystal phase and a Cu-rich phase. A section including a c-axis of the Th.sub.2Zn.sub.17 crystal phase has a first region in the crystal grain and a second region in the crystal grain, the first region is provided in the cell phase divided by the Cu-rich phase, the second region is provided within a range of not less than 50 nm nor more than 200 nm from the grain boundary phase in a direction perpendicular to an extension direction of the grain boundary phase, and a difference between a Cu concentration of the first region and a Cu concentration of the second region is 0.5 atomic percent or less.

The application provides a plaster casting mold fabrication method for a complicated structure aluminum alloy casting with a large inner cavity and a thin wall, in which, a wax pattern is cleaned with a mixture; closed blind cavity and large plane unbeneficial to plaster mold-filling of the wax pattern are used to exhaust air by using vent holes and waterproof-breathable membranes in cooperation with each other; under pressure difference, plaster powder and mixed aqueous solution are vertically splashed and mixed in a mixing tank to reduce dust discharge; asynchronous mixing and grouting can be realized by left and right mixing tanks in an upper tank of a vacuum tank. The present application can effectively remove the surface parting agent, increase the wettability of the plaster paste and the wax pattern surface, and improve the surface finish of the casting mold.

The application provides a plaster casting mold fabrication method for a complicated structure aluminum alloy casting with a large inner cavity and a thin wall, in which, a wax pattern is cleaned with a mixture; closed blind cavity and large plane unbeneficial to plaster mold-filling of the wax pattern are used to exhaust air by using vent holes and waterproof-breathable membranes in cooperation with each other; under pressure difference, plaster powder and mixed aqueous solution are vertically splashed and mixed in a mixing tank to reduce dust discharge; asynchronous mixing and grouting can be realized by left and right mixing tanks in an upper tank of a vacuum tank. The present application can effectively remove the surface parting agent, increase the wettability of the plaster paste and the wax pattern surface, and improve the surface finish of the casting mold.

Discussed herein are systems and methods of forming hardfacing coatings and films containing Q-carbon diamond particles for use in downhole drilling tooling and other tools where wear-resistant coating is desirable. The Q-carbon diamond-containing layers may be coated with matrix material and/or disposed in a matrix to form the coating, or the Q-carbon diamond layer may be formed directly from a diamond-like-carbon on a substrate.

Discussed herein are systems and methods of forming hardfacing coatings and films containing Q-carbon diamond particles for use in downhole drilling tooling and other tools where wear-resistant coating is desirable. The Q-carbon diamond-containing layers may be coated with matrix material and/or disposed in a matrix to form the coating, or the Q-carbon diamond layer may be formed directly from a diamond-like-carbon on a substrate.

A composite material comprising a metal matrix and nanocellulose supplement. The metal matrix is formed of a metal base material and may be monolithic throughout the composite material. The nanocellulose supplement improves a material property of the metal matrix and is formed of a nanocellulose supplement material dispersed in the metal base material. Importantly, the nanocellulose supplement material does not become damaged when the composite material is formed.

A composite material comprising a metal matrix and nanocellulose supplement. The metal matrix is formed of a metal base material and may be monolithic throughout the composite material. The nanocellulose supplement improves a material property of the metal matrix and is formed of a nanocellulose supplement material dispersed in the metal base material. Importantly, the nanocellulose supplement material does not become damaged when the composite material is formed.

The invention is directed to the interventionless activation of wellbore devices using dissolving and/or degrading and/or expanding structural materials. Engineered response materials, such as those that dissolve and/or degrade or expand upon exposure to specific environment, can be used to centralize a device in a wellbore.

The invention is directed to the interventionless activation of wellbore devices using dissolving and/or degrading and/or expanding structural materials. Engineered response materials, such as those that dissolve and/or degrade or expand upon exposure to specific environment, can be used to centralize a device in a wellbore.