A casting method of an active metal includes, in an induction melting furnace using a water-cooled crucible, tapping a molten metal into a mold from a tapping hole provided at a bottom of the water-cooled copper crucible to cast an ingot of the active metal. In conducting the casting under a casting condition in which the ingot has a diameter (D) of 10 mm or more and a ratio (H/D) of an ingot height H to the ingot diameter D of 1.5 or more and a weight of the molten metal tapped in the casting is 200 kg or less, a temperature of the molten metal in the casting is set to be higher than the melting point of the active metal and a casting velocity V (mm/sec) is controlled to satisfy V≤0.1H in relation with the ingot height H by adjusting an opening diameter of the tapping hole.

Provided is a cylinder liner having a first portion with a first thermal conductivity and a second portion with a second thermal conductivity. The first portion having the first thermal conductivity can include as-cast projections or a coating of a material, as desired. The first thermal conductivity can be greater than the second thermal conductivity. In this manner, the cylinder liner can exhibit a thermal conductivity gradient.

An outer layer of a rolling roll having a chemical composition comprising by mass 1.3-2.8% of C, 0.3-1.8% of Si, 0.3-2.5% of Mn, 0-6.5% of Ni, 1-10% of Cr, 0.9-6% of Mo, 0-8% of W, 0.5-6% of V, 0-3% of Nb, and 0% or more and less than 0.01% of B, the balance being Fe and inevitable impurities, and meeting the formulae (1): 1000117752C+14Si11Mn+6.8Cr+1W+0.65Mo+12V+15Nb1115, and (2): 5Cr+Mo+0.5W+V+1.2Nb15, wherein C, Si, Mn, Cr, W, Mo, V and Nb represent % by mass of these elements, and a structure containing eutectic carbide without graphite.

An outer layer of a rolling roll having a chemical composition comprising by mass 1.3-2.8% of C, 0.3-1.8% of Si, 0.3-2.5% of Mn, 0-6.5% of Ni, 1-10% of Cr, 0.9-6% of Mo, 0-8% of W, 0.5-6% of V, 0-3% of Nb, and 0% or more and less than 0.01% of B, the balance being Fe and inevitable impurities, and meeting the formulae (1): 1000117752C+14Si11Mn+6.8Cr+1W+0.65Mo+12V+15Nb1115, and (2): 5Cr+Mo+0.5W+V+1.2Nb15, wherein C, Si, Mn, Cr, W, Mo, V and Nb represent % by mass of these elements, and a structure containing eutectic carbide without graphite.

Various embodiments provide methods in which a metal matrix composite (MMC) material is incorporated into a metallic structure during a one-step near-net-shape structural forming process. Various embodiments provide in-situ selective reinforcement processes in which the MMC may be pre-placed on a forming tool in locations that correspond to specific regions in the metallic structure. Various embodiment near-net-shape structural forming processes may then be executed and result in various embodiment metallic structural components with selectively-reinforced regions that provide enhanced mechanical properties in key locations.

Various embodiments provide methods in which a metal matrix composite (MMC) material is incorporated into a metallic structure during a one-step near-net-shape structural forming process. Various embodiments provide in-situ selective reinforcement processes in which the MMC may be pre-placed on a forming tool in locations that correspond to specific regions in the metallic structure. Various embodiment near-net-shape structural forming processes may then be executed and result in various embodiment metallic structural components with selectively-reinforced regions that provide enhanced mechanical properties in key locations.

A method of fabricating an impregnated fiber assembly, the method including introducing a first suspension including a first powder of solid particles into an inside volume defined by an inside face of a first fiber texture of hollow shape placed in a mold, an outer face of the first fiber texture being present facing a wall of the mold; using a centrifugal force to impregnate the first fiber texture with the first suspension by rotating the mold; after impregnating the first texture, positioning a second fiber texture on the inside face of the first fiber texture to obtain a fiber assembly; introducing a second suspension including a second powder of solid particles into the inside volume after putting the second fiber texture into position; and using a centrifugal force to impregnate the second fiber texture with the second suspension by rotating the mold to obtain an impregnated fiber assembly.

A method of fabricating an impregnated fiber assembly, the method including introducing a first suspension including a first powder of solid particles into an inside volume defined by an inside face of a first fiber texture of hollow shape placed in a mold, an outer face of the first fiber texture being present facing a wall of the mold; using a centrifugal force to impregnate the first fiber texture with the first suspension by rotating the mold; after impregnating the first texture, positioning a second fiber texture on the inside face of the first fiber texture to obtain a fiber assembly; introducing a second suspension including a second powder of solid particles into the inside volume after putting the second fiber texture into position; and using a centrifugal force to impregnate the second fiber texture with the second suspension by rotating the mold to obtain an impregnated fiber assembly.

An outer layer of a rolling roll having a chemical composition comprising by mass 1.3-2.8% of C, 0.3-1.8% of Si, 0.3-2.5% of Mn, 0-6.5% of Ni, 1-10% of Cr, 0.9-6% of Mo, 0-8% of W, 0.5-6% of V, 0-3% of Nb, and 0% or more and less than 0.01% of B, the balance being Fe and inevitable impurities, and meeting the formulae (1): 1000117752C+14Si11Mn+6.8Cr+1W+0.65Mo+12V+15Nb1115, and (2): 5Cr+Mo+0.5W+V+1.2Nb15, wherein C, Si, Mn, Cr, W, Mo, V and Nb represent % by mass of these elements, and a structure containing eutectic carbide without graphite.

Provided is a cylinder liner having a first portion with a first thermal conductivity and a second portion with a second thermal conductivity. The first portion having the first thermal conductivity can include as-cast projections or a coating of a material, as desired. The first thermal conductivity can be greater than the second thermal conductivity. In this manner, the cylinder liner can exhibit a thermal conductivity gradient.