A rotary cutting tool includes a main body and a shank. The main body has a tip end. The shank is continuous with the main body on the side opposite to the tip end. The main body is provided with a first cutting edge having a positive twist angle, and a second cutting edge having a negative twist angle and separated from the first cutting edge. Each of the first cutting edge and the second cutting edge extends continuously from the tip end to the shank.

The present invention discloses a two-dimensional AlN material and its preparation method and application, wherein the preparation method comprises the following steps: (1) selecting a substrate and its crystal orientation; (2) cleaning the surface of the substrate; (3) transferring a graphene layer to the substrate layer; (4) annealing the substrate; (5) using the MOCVD process to introduce H.sub.2 to open the graphene layer and passivate the surface of the substrate; and (6) using the MOCVD process to grow a two-dimensional AlN layer. The preparation method of the present invention has the advantages that the process is simple, time saving and efficient. Besides, the two-dimensional AlN material prepared by the present invention can be widely used in HEMT devices, deep ultraviolet detectors or deep ultraviolet LEDs, and other fields.

Coated forming tool for processing of plastics materials or aluminum or aluminum alloy materials, comprising a substrate having a substrate surface, wherein the substrate surface is coated with a coating formed of one or more layers, wherein the coating comprises a Si—C—N-based layer having element composition in atomic percentage corresponding to Si.sub.aC.sub.bN.sub.cX.sub.d with 50<a+b+c≤100, 0≤d<60, preferably 0≤d<50, wherein X is one or more elements selected from the elements hydrogen, oxygen, titanium, chromium, and/or aluminum.

A method of making a negative electrode material for an electrochemical cell that cycles lithium ions is provided that includes centrifugally distributing a molten precursor comprising silicon and lithium by contacting the molten precursor with a rotating surface in a centrifugal atomizing reactor. The molten precursor is solidified to form a plurality of substantially round solid electroactive particles comprising an alloy of lithium and silicon and having a D50 diameter of less than or equal to about 20 micrometers. In certain variations, the negative electroactive material particles may further have one or more coatings disposed thereon, such as a carbonaceous coating and/or an oxide-based coating.

A sliding member (10) including a coating film (1) composed of a hard carbon layer on a sliding surface (16) of a base material (11). The coating film has, when a cross section thereof is observed by a bright-field TEM image, a thickness within a range of 1 μm to 50 μm, and is configured by repeating units including black hard carbon layers (B), relatively shown in black, and white hard carbon layers (W), relatively shown in white, and laminated in a thickness direction, and comprise an inclined region, provided on a base material side, where thicknesses of white hard carbon layers (W) of the repeating units gradually increase in a thickness direction, and a homogeneous region\, provided on a surface side of the sliding member, where thicknesses of the white hard carbon layers (W) of the repeating units are the same or substantially the same in the thickness direction.

To provide a magnesium alloy with improved corrosion resistance by surface modification, and a production method thereof. (1) The surface-modified magnesium alloy comprising: a magnesium alloy having an arbitrary shape; a magnesium fluoride layer formed by fluorination of the surface of the magnesium alloy; and a diamond-like carbon layer formed on the magnesium fluoride layer. (2) The method comprising: subjecting a surface of a magnesium alloy having an arbitrary shape to fluorination treatment to form a magnesium fluoride layer on the surface of the magnesium alloy, and then subjecting the magnesium alloy with the magnesium fluoride layer to be placed in a high-frequency plasma CVD device such that a source gas containing carbon is introduced to form a diamond-like carbon layer on the magnesium fluoride layer.

A protective coating layer, an electronic device including such a protective coating layer, and the methods of making the same are provided. The electronic device includes a substrate, a thin film circuit layer disposed over the substrate, and a protective coating layer disposed over the thin film circuit layer. The protective coating layer includes a first coating and a second coating disposed over the first coating. Each coating has a cross-plane thermal conductivity in a direction normal to a respective coating surface equal to or higher than 0.5 W/(m*K). The first coating and the second coating have different crystal structures, or different crystalline orientations, or different compositions, or a combination thereof to provide different nanoindentation hardness. The first coating has a hardness lower than that of the second coating.

Disclosed is a part comprising a metal substrate, a non-hydrogenated amorphous ta-C or aC carbon coating that coats the substrate, and an undercoat which is based on chromium (Cr), carbon (C) and silicon (Si) and is disposed between the metal substrate and the amorphous carbon coating and to which the amorphous carbon coating is applied, characterized in that the undercoat included, at its interface with the amorphous carbon coating, a ratio of silicon in atomic percent to chromium in atomic percent (Si/Cr) of 0.3 to 0.60, and a ratio of carbon in atomic percent to silicon in atomic percent (C/Si) of 2.5 to 3.5.

A sliding element for an internal combustion engine may include a base material having an annular external surface. The external surface may include a bonding layer, a first layer of coating, and a second layer of coating sequentially disposed thereon. The first layer of coating and the second layer of coating may include hard amorphous carbon (DLC) of a combined matrix having a plurality of sp3/sp2 bonds. The first layer of coating may include 45% sp3 bonds or less and may have a thickness of at least 10 micrometers. The second layer of coating may include at least 55% sp3 bonds and may have a thickness of at least 3 micrometers.

The present invention addresses the problem of providing a piston ring covered with a DLC coating that has excellent wear resistance and shows a low attacking property on a cylinder bore sliding surface. The problem is solved by a piston ring which is used in the presence of an engine lubricating oil and includes a DLC coating on an outer peripheral sliding surface. The DLC coating has an sp.sup.2 component ratio of 0.5 to 0.85 as determined from a TEM-EELS spectrum obtained by a combination of a transmission electron microscope (TEM) and electron energy loss spectroscopy (EELS), as well as a coating hardness of 12 GPa to 26 GPa and a Young's modulus of 250 GPa or less as measured by a nanoindentation method.