The present disclosure relates to a wear part made in a foundry. The wear part has a reinforced portion comprising a ferrous alloy reinforced with metal carbides, nitrides, borides, or intermetallic alloys. The reinforced portion includes inserts of metal carbides, nitrides, metal, or intermetallic compounds manufactured beforehand with a defined geometry and inserted into an infiltrable structure of agglomerated grains including the reagents needed for the formation of metal or intermetallic carbides, nitrides, borides according to an in situ self-propagating thermal reaction initiated during the casting of the ferrous alloy.

The present disclosure relates to a hierarchical wear part including a reinforced portion comprising zirconia or an alumina-zirconia alloy. The reinforced portion also includes centimetric inserts with a predefined geometry. The inserts include micrometric particles of metal carbides, nitrides, borides, or intermetallic compounds bonded by a first metal matrix. The inserts are inserted into a reinforcement structure infiltrated by a second metal matrix, the reinforcement structure having a periodic alternation of millimetric areas of high and low concentration of micrometric particles of zirconia or alumina-zirconia alloy. The second metal matrix is different from the first metal matrix.

A composite wear pad includes a substrate that is selected from the group of iron based alloys, steel, nickel based alloys, and cobalt based alloys. A hard particle-matrix alloy layer is bonded at a surface to the substrate. The hard particle-matrix alloy layer has a plurality of hard particles dispersed in a matrix alloy. The hard particle-matrix alloy layer has a thickness ranging between greater than about 13 millimeters and about 20 millimeters.

A composite wear pad includes a substrate that is selected from the group of iron based alloys, steel, nickel based alloys, and cobalt based alloys. A hard particle-matrix alloy layer is bonded at a surface to the substrate. The hard particle-matrix alloy layer has a plurality of hard particles dispersed in a matrix alloy. The hard particle-matrix alloy layer has a thickness ranging between greater than about 13 millimeters and about 20 millimeters.

The present application discloses a ceramic preform, a method of making a ceramic preform and a metal matrix composite comprising a ceramic preform. In one exemplary embodiment, the ceramic preform comprises a ceramic compound compressed into the shape of a cylinder by rotational compression molding. The cylinder has an inner surface and an outer surface. A first liner may be attached to the inner surface of the cylinder and a second liner may attached to the outer surface of the cylinder. The metal matrix composite of the present application may be formed as a brake drum or a brake disc.

In one aspect, methods of making freestanding metal matrix composite articles and alloy articles are described. A method of making a freestanding composite article described herein comprises disposing over a surface of the temporary substrate a layered assembly comprising a layer of infiltration metal or alloy and a hard particle layer formed of a flexible sheet comprising organic binder and the hard particles. The layered assembly is heated to infiltrate the hard particle layer with metal or alloy providing a metal matrix composite, and the metal matrix composite is separated from the temporary substrate. Further, a method of making a freestanding alloy article described herein comprises disposing over the surface of a temporary substrate a flexible sheet comprising organic binder and powder alloy and heating the sheet to provide a sintered alloy article. The sintered alloy article is then separated from the temporary substrate.

One aspect relates to a process for producing a sintered workpiece, which includes sintering of a ceramic material at a temperature of at least 1000° C. and in an atmosphere, in the case of which the partial pressure of atmospheric air is reduced to less than 10.sup.−6-times, based on the ambient air at the same temperature under equilibrium conditions.

A composite member excellent in corrosion resistance of a substrate and excellent in heat radiation property is provided. A composite member includes a substrate composed of a composite material containing magnesium or a magnesium alloy and SiC and a coating layer provided on a surface of the substrate. The coating layer includes an outermost layer provided as an outermost surface and an intermediate layer provided directly under the outermost layer. The outermost layer contains nickel and phosphorus. The intermediate layer is mainly composed of copper. The intermediate layer has a thickness not smaller than 30 μm.

An aluminum porous body has a skeleton with a three-dimensional network structure, in which the skeleton is formed of an aluminum layer containing aluminum carbide, and when the aluminum porous body is subjected to XRD measurement, diffraction peaks originating from aluminum carbide are detected at two peak positions in a 2θ range of 30.8° or more and 31.5° or less and a 2θ range of 31.6° or more and 32.3° or less.

A refractory composition for forming a working lining in a metallurgical vessel contains a coarse-grain refractory particle fraction and a fine-grain refractory particle fraction, or at least 0.25% additive calcium oxide, or at least 0.25% titanium dioxide. The coarse-grain refractory particles can include alumina particles, magnesia particles, magnesium aluminate spinel particles, zirconia particles, or doloma particles, or a combination of any of these particles. The fine-grain refractory particles can be comprised of any low-magnesia refractory oxide. The refractory composition can be applied to a metallurgical vessel by spraying, gunning, shotcreting, vibrating, casting, troweling, or positioning preformed refractory shapes, or a combination of any of these techniques. When contacted by molten metal, the molten metal penetrates into the refractory material, wetting the coarse-grain refractory particles, and forming a refractory-metal composite barrier layer that decreases or blocks oxygen transport through the refractory lining.