Abstract: To provide a tin-silver based lead-free solder which can improve joint strength in the initial stage, and can curtail a decrease in joint strength after heat treatment, at a joined interface with an electroless plating, zinc (Zn) is added to a solder comprising a tin-silver system containing no lead.

Abstract: A valve seat (2) is formed by build-up cladding by irradiating a laser beam on a copper alloy powder (4) provided in the rim of a port (3) formed in an engine cylinder head (1). The copper alloy powder (4) consists of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (Si), and 1-5 wt % of one of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V). Due to this composition, the valve seat (2) has few microcracks and excellent abrasion resistance.

Abstract: A tin-silver-based soldering alloy, comprises 3.0 to 4.0% by weight of Ag, 6.05 to 10.0% by weight of In, 2.0 to 5.95% by weight of Bi, and the balance being Sn, wherein In+Bi≦12.0% by weight.

Abstract: A valve seat (2) is formed by build-up cladding by irradiating a laser beam on a copper alloy powder (4) provided in the rim of a port (3) formed in an engine cylinder head (1). The copper alloy powder (4) consists of copper (Cu), 6-9 wt % nickel (Ni), 1-5 wt % silicon (si), and 1-5 wt % of one of molybdenum (Mo), tungsten (W), tantalum (Ta), niobium (Nb) and vanadium (V). Due to this composition, the valve seat (2) has few microcracks and excellent abrasion resistance.

Abstract: A wire for use in robot including a conductor of metallic fiber-reinforced copper matrix composite whose plastic strain to rupture is substantially less than 0.2%. A plurality of conductors form a twisted wire (2). An insulation member (4) is coated on the twisted wire (2) to form a coated wire (6). The conductivity of the conductor is greater than 70% IACS and the tensile strength of the conductor is greater than 100 Kg/mm.sup.2. The metallic fiber-reinforced copper matrix composite is in-situ metallic fiber-reinforced copper matrix composite drawn with a total reduction in sectional area of 99.99% or more.

Abstract: The present invention provides a lead-free tin-silver-based soldering alloy which has a low melting point equal to alloy H without containing harmful lead, expensive In or the like, and has excellent mechanical characteristics, that is, a tensile strength, an elongation value and heat fatigue characteristic as compared with alloy H, and thus, is applicable to soldering work at a low temperature and can make products which have a high reliability and long useful life or durability. The lead-free tin-silver-based soldering alloy consists essentially of Ag: 2 to 4% by weight, Zn: 0.5 to 2% by weight, Bi: 2 to 6% by weight, and the balance being substantially Sn.

Abstract: The present invention provides a soldering alloy which does not include harmful Pb or Cd and which has an excellent tensile strength, elongation value, and melting point property. The soldering alloy according to the present invention can thus solve the conventional environmental problems, set the soldering temperature at a low level to thereby restrict the thermal damage to a soldered portion, and prevent breaking of the soldering alloy due to a heat cycle, with an excellent tensile strength and elongation value. A tin-silver-based soldering alloy according to the present invention consist essentially of 3 to 4% by weight of Ag, 2 to 6% by weight of Bi, 2 to 6% by weight of In, and the balance being Sn.

Abstract: An abrasion resistant copper alloy suitable for the material of an overlaid layer formed at the valve seat of an engine cylinder head formed of aluminum alloy. The copper alloy consists essentially of nickel in an amount ranging from 10 to 30% by weight; silicon in an amount ranging from 0.5 to 5.0% by weight; at least one element selected from the group consisting of molybdenum, tungsten, tantalum, niobium and vanadium, in an amount ranging from 2.0 to 15.0% by weight; and balance being copper and impurities.

Abstract: Described is a lead-free tin-zinc-based soldering alloy made up of 7 to 9 wt. % of Zn and 0.1 to 0.5 wt. % of Cu or which further contains not more than 3 wt. % of Bi and, in either case, the balance being Sn except for inevitable impurities. The present invention has made it possible to provide a lead-free soldering alloy which has mechanical properties, such as tensile strength and elongation, comparable with those of conventional Pb--Sn soldering alloys without adding thereto lead which causes environmental pollution, has a melting point not higher than 200.degree. C., which is lower than the heat-resistant temperature of an IC package, and has a low cost.

Abstract: A lead-free solder consisting of 1 to 4 wt % of Ag, at least one of Bi and In in respective amounts meeting the conditions that the value of expression (1), A, is equal to or greater than 5.00 and that the value of expression (2), B, is equal to or less than 6.90, and Sn for the balance:A=[Ag wt %]+1.23 [Bi wt %]+0.52 [In wt %] (1)B=[Ag wt %]+1.19 [Bi wt %]+0.50 [In wt %] (2)This solder has a tensile strength and an elongation as high as those of conventional Pb--Sn solder without containing neither lead nor cadmium, which can cause environmental contamination.

Abstract: A method of controlling a single temperature type water/hydrogen isotopic exchange reaction plant comprising an electrolytic system, an exchange reaction column and a recombining system for separating degraded heavy water into product and waste both of which have a stable concentration. The control method comprises controlling an extracting quantity of waste so that a heavy water concentration of water at an intermediate portion of the reaction column is kept constant, and controlling an extracting quantity of product so that a water quantity inside the exchange reaction plant is kept constant.