A sliding member incudes a back-metal layer and a sliding layer made of a copper alloy. The back-metal layer is made of a hypoeutectoid steel including 0.07 to 0.35 mass % of carbon, and has a structure including a ferrite phase and pearlite. The back-metal layer includes a pore existing region including a plurality of closed pores having an average size of 1 to 10 μm. The pore existing region extends from the bonding surface toward an inner portion of the back-metal layer and having a thickness of 2 to 20 μm. At least a part of the plurality of closed pores has contour that is partially formed by the bonding surface in a cross-sectional view. A ratio V2/V1 of a total volume V2 of the closed pores to a volume V1 of the pore existing region is 0.02 to 0.08.

A carburized steel component, comprising a steel base including, by weight percent, from 0.08% to 0.35% carbon, 0.5% to 1.3% manganese, 0% to 0.35% silicon, 0.2% to 2.0% chromium, 0% to 4% nickel, 0% to 0.50% molybdenum, 0% to 0.06% niobium, and a remaining weight percent of iron, and a carburized layer of above 0.35% by weight carbon from a surface of the carburized layer to a carburized layer depth, wherein the carburized layer depth is from 0.5 mm to 3.0 mm, wherein the carburized layer comprises a microstructure including martensite, retained austenite, carbide, and less than 2% by volume non-martensitic transformation products (NMTP), and wherein the carburized layer includes a prior austenite average grain size of 3.0-8.0 microns from the surface to a depth of at least 0.2 mm.

A polycrystalline diamond (PCD) construction has a first region of a first grade of PCD material; and a second region of a second grade of PCD material, the first region being at least partially peripherally surrounded by the second region, the first and second regions being bonded to each other by direct inter-growth of diamond grains to form an integral PCD structure and a substrate bonded to the first and/or second region(s) along an interface. The first grade of PCD differs from the second grade in one or more of diamond and metal network compositional ratio, metal elemental composition, or average diamond grain size, the first grade of PCD material having a larger average diamond grain size than the second grade of PCD material, and/or a smaller volume percentage of residual catalyst and/or binder in interstitial spaces between interbonded diamond grains than the PCD material of the second region.

A method for producing a high-strength galvanized steel sheet having excellent fatigue resistance properties. The method includes an oxidation processing in which a steel sheet is heated at a temperature of 400 to 750° C. in an atmosphere having an O.sub.2 concentration of 1000 ppm by volume or more and a H.sub.2O concentration of 1000 ppm by volume or more, and the steel sheet is heated at a temperature of 600 to 850° C. in an atmosphere having an O.sub.2 concentration of less than 1000 ppm by volume and a H.sub.2O concentration of 1000 ppm by volume or more. The method also includes reduction-annealing in which the steel sheet is heated at a heating rate of 0.1° C./sec or more to a temperature of 650 to 900° C. in an atmosphere having a H.sub.2 concentration of 5 to 30 vol % and a H.sub.2O concentration of 10 to 1000 ppm by volume.

A sliding member incudes a back-metal layer and a sliding layer made of a copper alloy. The back-metal layer is made of a hypoeutectoid steel including 0.07 to 0.35 mass % of carbon, and has a structure including a ferrite phase and pearlite. The back-metal layer includes a pore existing region including a plurality of closed pores having an average size of 1 to 10 μm. The pore existing region extends from the bonding surface toward an inner portion of the back-metal layer and having a thickness of 2 to 20 μm. At least a part of the plurality of closed pores has contour that is partially formed by the bonding surface in a cross-sectional view. A ratio V2/V1 of a total volume V2 of the closed pores to a volume V1 of the pore existing region is 0.02 to 0.08.

In an embodiment, a polycrystalline diamond compacts (PDC) includes a substrate and a polycrystalline diamond (PCD) table bonded to the substrate. The PCD table defines an upper surface and at least one peripheral surface. The PCD table includes a plurality of bonded diamond grains. The PCD table includes a first region adjacent to the substrate that includes a metallic constituent disposed interstitially between the bonded diamond grains thereof, and a leached second region extending inwardly from the upper surface and the at least one peripheral surface that is depleted of the metallic constituent. The leached second region exhibits a leach depth profile having a maximum leach depth that is measured from the upper surface. A leach depth of the leach depth profile decreases with lateral distance from a central axis of the PCD table and toward the at least one peripheral surface.

A method of fabricating a cemented carbide article by additive manufacturing, and a granular material are disclosed. A precursor material is provided that comprises granules, the granules comprising carbide grains and a binder comprising any of cobalt, nickel and iron. Each granule has a density of at least 99.5% of the theoretical density and the granules of the precursor material have a mean compressive strength of at least 40 megapascals (MPa). An additive manufacturing process is used to manufacture the article by building up successive layers of material derived from the precursor material.

Induced material segregation methods of manufacturing a polycrystalline diamond compact (PDC) cutter result in formation of a polycrystalline diamond/tungsten carbide (WC) composite material having a smooth compositional gradient from maximum WC concentration at one face to maximum diamond concentration at another face. Because the compositional gradient is smooth, very little or no mismatch of coefficient of thermal expansion occurs, which improves a service lifetime of the PDC cutter.

A press-hardened steel is provided. The press-hardened steel has an alloy matrix including from about 0.01 wt. % to about 0.35 wt. % carbon, from about 1 wt. % to about 9 wt. % chromium, from about 0.5 wt. % to about 2 wt. % silicon, and a balance of iron. The alloy matrix is greater than or equal to about 95 vol. % martensite. A first layer is disposed directly on the alloy matrix. The first layer is continuous, has a thickness of greater than or equal to about 0.01 m to less than or equal to about 10 m, and includes an oxide enriched with chromium and silicon. A second layer is disposed directly on the first layer, and includes an oxide enriched with Fe. Methods of preparing the press-hardened steel are also provided.

The invention relates to a PCD composite compact element comprising a PCD structure integrally bonded at an interface to a cemented carbide substrate; the PCD structure comprising coherently bonded diamond grains having a mean size no greater than 15 microns; the cemented carbide substrate comprising carbide particles dispersed in a metallic binder, the carbide particles comprising a carbide compound of a metal; wherein the ratio of the amount of metallic binder to the amount of the metal at points in the substrate deviates from a mean value by at most 20 percent of the mean value. The invention further relates to a method for making a PDC compact element comprising a PCD structure integrally bonded to a substrate formed of cemented carbide; the method including introducing a source of excess carbon to the substrate at a bonding surface of the substrate to form a carburised substrate; contacting an aggregated mass of diamond grains with the carburised substrate; and sintering the diamond grains in the presence of a solvent/catalyst material for diamond; wherein the mean size of the diamond grains in the aggregated mass is no greater than 30 microns.