A ceramic tool material, in particular with piezoelectric effect and a preparation method thereof, and a cutting tool. The ceramic tool material includes the following raw materials by weight: 30-70 parts of matrix material, 30-70 parts of piezoelectric material, 5-10 parts of binder, and 10-20 parts of reinforcing phase and can be made into cutting tools. The cutting tool has a piezoelectric effect and excellent mechanical properties and can convert the cutting force signal into the charge signal during machining. By collecting charge signals, a cutting force can be measured and ceramic cutting tool condition can be monitored. Cutting force measurement function and high mechanical properties are integrated. A ceramic tool material with piezoelectric effect can measure the cutting force on the premise by meeting the cutting performance requirements.

A sintered friction material is formed by pressure sintering mixed powder at 800° C. or above, the mixed powder consisting of, in mass %, Cu and/or Cu alloy: 40.0 to 80.0%, Ni: 0% or more and less than 5.0%, Sn: 0 to 10.0%, Zn: 0 to 10.0%, VC: 0.5 to 5.0%, Fe and/or Fe alloy: 2.0 to 40.0%, lubricant: 5.0 to 30.0%, metal oxide and/or metal nitride: 1.5 to 30.0%, and the balance being impurity.

A composite structure with an aluminum-based alloy layer containing boron carbide and a manufacturing method thereof are provided. The composite structure includes a substrate with an open hole in that surface and the aluminum-based alloy layer containing boron carbide. The aluminum-based alloy layer is disposed in the open hole and contains aluminum, boron, carbon, and oxygen, wherein the content of aluminum is between 4 at. % and 55 at. %, the content of boron is between 9 at. % and 32 at. %, the content of carbon is between 13 at. % and 32 at. %, the content of oxygen is between 2 at. % and 38 at. %, and the ratio of the content of boron to carbon is between 0.3 and 2.7.

Disclosed herein, in certain embodiments, are composite materials, methods, tools and abrasive materials comprising a tungsten-based metal composition, a tungsten carbide, and an alloy. In some cases, the composite materials or matrix are resistant to oxidation.

Disclosed herein, in certain embodiments, are composite materials, methods, tools and abrasive materials comprising a tungsten-based metal composition, a tungsten carbide, and an alloy. In some cases, the composite materials or matrix are resistant to oxidation.

A multicomponent alloy coating is provided. The multicomponent alloy coating includes a hard layer and a plurality of nickel-based particles dispersed in the hard layer. The composition of the multicomponent alloy coating is represented by the following formula (I):
Al.sub.dCo.sub.eCr.sub.gFe.sub.hNi.sub.iSi.sub.jC.sub.kO.sub.m  formula (I), wherein 1<d<2, 0.5<e<0.8, 2<g<3.2, 0.05<h<0.3, 2<i<3, j=1, k≥0, m≥0, and iron is present in the amount of less than 3 wt % of the composition of the multicomponent alloy coating.

A thixomolding material includes: a metal body that contains Mg as a main component; and a coating portion that is adhered to a surface of the metal body via a binder and contains SiO.sub.2 particles containing SiO.sub.2 as a main component. An average particle diameter of the SiO.sub.2 particles is less than 20.0 μm, and a mass fraction of the SiO.sub.2 particles in a total mass of the metal body and the SiO.sub.2 particles is 1.0 mass % or more and 40.0 mass % or less. The binder may contain waxes. A content of the binder may be 0.001 mass % or more and 0.200 mass % or less.

A composite structure with an aluminum-based alloy layer containing boron carbide and a manufacturing method thereof are provided. The composite structure includes a substrate with an open hole in that surface and the aluminum-based alloy layer containing boron carbide. The aluminum-based alloy layer is disposed in the open hole and contains aluminum, boron, carbon, and oxygen, wherein the content of aluminum is between 4 at. % and 55 at. %, the content of boron is between 9 at. % and 32 at. %, the content of carbon is between 13 at. % and 32 at. %, the content of oxygen is between 2 at. % and 38 at. %, and the ratio of the content of boron to carbon is between 0.3 and 2.7.

A reinforced magnesium composite, and a method of producing thereof, wherein the reinforced magnesium composite comprises elemental magnesium particles, elemental nickel particles, and one or more ceramic particles with elemental nickel particles being dispersed within elemental magnesium particles without having intermetallic compounds therebetween. Various embodiments of the method of producing the reinforced magnesium composite are also provided.

There is provided a sintered friction material for railway vehicles that has excellent frictional properties and wear resistance even in a high speed range of 280 km/hour or more. The sintered friction material for railway vehicles is a green compact sintered material containing, in mass %, Cu: 50.0 to 75.0%, graphite: 5.0 to 15.0%, one or more selected from the group consisting of magnesia, zircon sand, silica, zirconia, mullite, and silicon nitride: 1.5 to 15.0%, one or more selected from the group consisting of W and Mo: 3.0 to 30.0%, and one or more selected from the group consisting of ferrochromium, ferrotungsten, ferromolybdenum, and stainless steel: 2.0 to 20.0%, with the balance being impurities.