Abstract: A forming method wherein a billet (31, 66, 77, 87, 107, 128, 136, 144, 153, 77B, 77C) comprising a metal-based composite material (27) prepared by mixing an aluminum alloy (22) and a ceramic (15) is subjected to pressure forming to manufacture a formed article, which comprises carrying out the pressure forming by the use of different compression ratios for different portions of the formed article, wherein a compression ratio means the ratio of the height of a billet before the pressure forming to height of the billet after the pressure forming. The above forming method allows the manufacture of a formed article having different volume contents 8 Vf) of the ceramic for different portions thereof.

Abstract: The invention relates to a Group III nitride-based compound semiconductor light-emitting device having a well layer, a first layer formed on one surface of the well layer, a second layer formed on the other surface of the well layer, a first region provided in the vicinity of the interface between the first layer and the well layer, and a second region provided in the vicinity of the interface between the second layer and the well layer, wherein the first and second regions are formed such that the lattice constants of the first and second layers approach the lattice constant of the well layer.

Abstract: A thin and large high toughness die-cast product is provided that is formed from an Al—Mg casting alloy having the composition 3.5 wt %?Mg?4.5 wt %, 0.8 wt %?Mn?1.5 wt %, Si?0.5 wt %, Fe?0.5 wt %, a sum (Ti+Zr) of amounts of Ti and Zr added of equal to or greater than 0.3 wt %, and a ratio (Ti/Zr) of the amounts of Ti and Zr added of at least 0.3 but not more than 2, with the balance being Al.

Abstract: A brake drum has its strength elevated in its disk portion. The brake drum is formed from a composition having ceramics dispersed in a matrix. The disk portion has a high ceramic content and thereby a high strength. Its cylindrical portion has a ceramic content decreasing gradually from the outer edge of the disk portion.

Abstract: A ribbed die cast product includes a plate-shaped main body and at least one rib provided on a back surface of the main body. The die cast product is made of an Al—Mg alloy. A first imaginary straight line runs along a lengthwise direction of the rib and intersects a plurality of second imaginary straight lines that run along the flow of molten metal in the main body.

Abstract: A slide surface construction is formed of a large number of truncated hexagonal pyramid-shaped metal crystals in a slide surface, with the area rate A of said truncated hexagonal pyramid-shaped metal crystals being in a range of 40%≦A≦100%. A top face of each of the truncated hexagonal pyramid-shaped metal crystals has a plurality of flat face portions, with a step provided between adjacent ones of the flat face portions. Each of the truncated hexagonal pyramid-shaped metal crystals is a (hhh) oriented metal crystal which has a body-centered cubic structure and whose (hhh) plane (by Miller indices) is oriented toward the slide surface.

Abstract: An aluminum-based composite member having an increased strength of bond between an aluminum-based body and a cast iron material portion which is incorporated into the aluminum-based body by casting is provided by an improved process. The following steps are employed in the process: a step of removing an oxide film on the surface of the cast iron material portion and activating such surface; a step of forming a protecting plated-layer having a thickness a in a range of 0.8 .mu.m.ltoreq.a.ltoreq.5 .mu.

Abstract: A slide surface construction is formed of an aggregate of metal crystals. The area rate A of hexagonal pyramid-shaped metal crystals in a slide surface of the slide surface construction is in a range of A.gtoreq.40%, and the Co (cobalt) content in the aggregate is in a range of Co.gtoreq.13% by weight. The metal crystals are preferably Fe (ferrous) crystals. The slide surface takes on an intricate aspect due to the existing of a large number of hexagonal pyramid-shaped metal crystals and hence, has a good oil retention. In addition, the wearing of the hexagonal pyramid-shaped metal crystals is inhibited due to an increase in hardness resulting from the incorporation of Co and therefore, the oil retention is maintained. Thus, the slide surface construction exhibits an excellent seizure resistance.

Abstract: A slide surface construction of a slide bearing is formed of an aggregate of two different metal crystals. The sliding condition of a first region of the slide bearing is more severe than that of a second region. The (2hhh) oriented metal crystals having a body-centered cubic structure with their (2hhh) planes (by Miller indices) oriented toward a slide surface exist in the first region. The content S.sub.2hhh of the (2hhh) oriented metal crystals is set in a range of S.sub.2hhh .gtoreq.20%. These crystals have a high hardness and are in the form of fish-like metal crystals in the slide surface and hence, an aggregate of these metal crystals has a good oil retention. The (hhh) oriented metal crystals having a body-centered cubic structure with their (hhh) planes (by Miller indices) oriented toward a slide surface exist in the second region. The content S.sub.hhh of the (hhh) oriented metal crystals is set in a range of S.sub.hhh .gtoreq.40%.

Abstract: A slide surface construction is formed of an aggregate of metal crystals on a surface of a slide member. The area rate A of pyramid-shaped metal crystals in the slide surface is in the range of A.gtoreq.40%, and the oxygen (O) content and/or the phosphorous (P) content in the aggregate is in a range of 0.gtoreq.0.2% by weight and P.gtoreq.0.04% by weight. The slide surface takes on an intricate aspect due to the presence of the large number of hexagonal pyramid-shaped metal crystals and hence, has a good oil retention. In addition, the wearing of the hexagonal pyramid-shaped metal crystals is inhibited by an increase in hardness caused by the oxygen contained, and therefore, the oil retention is maintained. Thus, the slide surface construction exhibits an excellent seizure resistance. In addition to oxygen (O) and/or phosphorous (P), the elements that may be added to the aggregate include hydrogen (H), carbon (C) and boron (B).

Abstract: A slide surface construction is formed of an aggregate of Fe crystals on a surface of a slide member such as a piston, cylinder, piston ring of the like. The area rate A of hexagonal pyramid-shaped Fe crystals in the slide surface is in the range of 40%.ltoreq.A.ltoreq.100%, and the content of Ni in the aggregate is in a range of 1% by weight.ltoreq.Ni.ltoreq.40% by weight. The slide surface takes on an intricate aspect due to the presence of a large number of hexagonal pyramid-shaped Fe crystals and hence, has a good oil retention. The slide surface construction exhibits an excellent corrosion resistance, because it contains nickel (Ni) or chromium (Cr) or both. Thus, the corrosion of the pyramid-shaped Fe crystals is inhibited in a corrosive sliding environment and hence, the oil retention is maintained.