A composite cemented carbide roll comprising an inner layer made of an iron-based alloy, and an outer layer made of cemented carbide which is metallurgically bonded to an outer peripheral surface of the inner layer; the cemented carbide of the outer layer comprising 55-90 parts by mass of WC particles and 10-45 parts by mass of an Fe-based binder phase having a particular composition; a shaft member and a shaft end member being metallurgically bonded to at least one axial end of the inner layer; the inner layer being made of an iron-based alloy containing 2.0% or more in total by mass of at least one selected from the group consisting of Cr, Ni and Mo; and the shaft member and the shaft end member being made of an iron-based alloy containing 1.5% or less in total by mass of at least one selected from the group consisting of Cr, Ni and Mo.

Cutters for a downhole drill bit can be formed by providing a catalyst-free synthesized polycrystalline diamond (PCD) having a cross-sectional dimension of at least 8 millimeters; providing a substrate comprising tungsten carbide; and attaching the synthesized PCD to the substrate comprising tungsten carbide to form a PDC cutter.

Disclosed herein is a method comprising disposing a container containing a metal and/or ferromagnetic solid and abrasive particles in a static magnetic field; where the container is surrounded by an induction coil; activating the induction coil with an electrical current, to heat up the metallic or ferromagnetic solid to form a fluid; generating sonic energy to produce acoustic cavitation and abrasion between the abrasive particles and the container; and producing nanoparticles that comprise elements from the container, the metal and/or the ferromagnetic solid and the abrasive particles. Disclosed herein too is a composition comprising first metal or a first ceramic; and particles comprising carbides and/or nitrides dispersed therein. Disclosed herein too is a composition comprising nanoparticles comprising chromium carbide, iron carbide, nickel carbide, γ-Fe and magnesium nitride.

To provide a powder material for additive layer manufacturing capable of molding a three-dimensional shaped molded article having less cracking or chipping and having high hardness and a method for manufacturing a molded article using the powder material. A powder material for additive layer manufacturing used to manufacture a three-dimensional shaped molded article by irradiation with a laser light or an electron beam contains cobalt, a first component containing one or more substances selected from the group consisting of vanadium carbide, niobium carbide, and molybdenum carbide, an optional additive component, and the balance of tungsten carbide. The content of the first component is 0.6% by mass or more and 5% by mass or less.

Disclosed herein are structures comprising a titanium, zirconium, or hafnium powder particle with titanium carbide, zirconium carbide, or hafnium carbide (respectively) nano-whiskers grown directly from and anchored to the powder particle. Also disclosed are methods for fabrication of such structures, involving heating the powder particles and exposing the particles to an organic gas.

A preparation method of cemented carbide with FeCoCu medium-entropy alloy as binding phase is provided. The preparation method includes: 1) preparing FeCoCu precursor powders by solution combustion synthesis; 2) preparing FeCoCu medium-entropy alloy powders by mechanical alloying; 3) evenly mixing the FeCoCu medium-entropy alloy powders with ultra-fine WC powders and a binder to obtain mixed powders and pressing the mixed powders into a shaped green body; 4) preparing a WC-FeCoCu cemented carbide by microwave sintering after removing the binder from the shaped green body. The preparation method reduces sintering temperature and time and obtains a new-type cemented carbide with fine grains, high hardness and good toughness while reducing the cost.

The invention is a process for manufacturing a nano aluminum/alumina metal matrix composite and composition produced therefrom. The process is characterized by providing an aluminum powder having a natural oxide formation layer and an aluminum oxide content between about 0.1 and about 4.5 wt. % and a specific surface area of from about 0.3 and about 5 m.sup.2/g, hot working the aluminum powder, and forming a superfine grained matrix aluminum alloy. Simultaneously there is formed in situ a substantially uniform distribution of nano particles of alumina. The alloy has a substantially linear property/temperature profile, such that physical properties such as strength are substantially maintained even at temperatures of 250° C. and above.

A metal-matrix composite tool includes a matrix region. The matrix region has a reinforcement material, an outer surface, and an inner, localized area spaced apart from the outer surface within the reinforcement material. The reinforcement material has a reinforcement density and the localized area has a localized density different from the reinforcement density. The matrix region has an overall matrix density different from both the reinforcement density and the localized density.

The present invention relates to a coated cutting tool including a Cr-containing cemented carbide substrate having WC, a binder phase and a gamma phase. The cemented carbide includes a gradient surface zone with a thickness of between 2 to 100 μm, which is binder phase enriched and depleted of gamma phase. The cemented carbide includes M.sub.7C.sub.3 carbides in an amount of between 0.5 to 7 area % measured in the bulk, where M is elements being Cr, W and at least one binder metal. The coated cutting inserts shows an improved edge line toughness.

A hierarchical composite wear component may have a reinforcement in the most exposed part to wear, the reinforcement including a three-dimensionally interconnected network of periodically alternating millimetric ceramic-metal composite granules with millimetric interstices. The ceramic-metal composite granules have at least 52 vol %, preferably at least 61 vol %, more preferably at least 70 vol % of micrometric particles of titanium carbide embedded in a first metal matrix. The ceramic-metal composite granules have a density of at least 4.8 g/cm.sup.3. The three-dimensionally interconnected network of ceramic-metal composite granules with its millimetric interstices is embedded in the second metal matrix. The reinforcement has on average at least 23 vol %, more preferably at least 28 vol %, most preferably at least 30 vol % of titanium carbide, the first metal matrix being different from the second metal matrix, the second metal matrix including a ferrous cast alloy.