Abstract: The present invention is to provide a method for laser welding different kinds of metals by which at least two types of metal members having mutually different laser reflection factor, are put one upon another and welded when the metal members are irradiated with lasers emitted in the superposed direction, comprising a process to put the first metal member on the second metal member, wherein the first metal member has a first laser reflection factor and the second metal member has a second laser reflection factor which is lower than that of the aforementioned first laser reflection factor, and the first and the second metal member are put one upon another through a metal layer and when irradiated with lasers, the aforementioned metal layer is more difficult to melt than the aforementioned second metal member. The method of the present invention further comprises a process in which lasers are irradiated from the aforementioned first metal member side.

Abstract: A steel having good wear resistance which contains 0.55-1.10% of C, up to 2.0% of Si, up to 2.0% of Mn, 12.0-25.0% of Cr and particularly suitable as a material for piston rings or rocker arms. Further addition of 0.05-1.10% of Al to the above steel gives a steel improved in properties for spheroidization of carbides and uniformization of carbide particle size, leading to further enhancement of wear resistance. If required 0.20-2.0% of Ni may be added to the steels, whereby corrosion resistance, toughness and hardenability are improved. An addition of at least one of 0.2-3.0% of Mo, 0.1-1.5% of V and 0.05-0.70% of Nb to the steels improves high-temperature strength and surface hardness. The steel is surface treated by gas nitriding of the like in a surface area for sliding contact with an opponent member.

Abstract: A steel having good wear resistance which contains 0.55-1.10% of C, up to 2.0% of Si, up to 2.0% of Mn, 12.0-25.0% of Cr and particularly suitable as a material for piston rings or rocker arms. Further addition of 0.05-1.10% of Al to the above steel gives a steel improved in properties for spheroidization of carbides and uniformization of carbide particle size, leading to further enhancement of wear resistance. If required 0.20-2.0% of Ni may be added to the steels, whereby corrosion resistance, toughness and hardenability are improved. An addition of at least one of 0.2-3.0% of Mo, 0.1-1.5% of V and 0.05-0.70% of Nb to the steels improves high-temperature strength and surface hardness. The steel is surface treated by gas nitriding of the like in a surface area for sliding contact with an opponent member.

Abstract: A process for producing a metallic catalyst-carrier, comprising the steps of: preparing a steel sheet containing 9.0 to 25.0 wt % Cr and 0.01 to 6.0 wt % Al, plating the steel sheet with Ni at an amount of from 0.3 to 10.0 g/m.sup.2, then plating with Al or Al-alloy at a plated amount defined by the formula; ##EQU1## and with a provision that the thickness of an Al-Fe alloyed layer is controlled to a thickness of 10 .mu.m or less, cold rolling to a rolled thickness of 0.1 mm or less, working to a body of a required form, and heat-treating the body.