Abstract: A method for forming an insulating layer in an oxide high-temperature superconductor is described. The oxide high-temperature superconductor is exposed to radiation, whereby an interface showing superconducting characteristics and/or a weak link that is present at an interface in the said oxide high-temperature superconductor is transformed to a thin insulating layer.

Abstract: A high-strength, heat-resisting ferritic steel pipe or tube for boiler use containing 0.03 to 0.15% C, 0.1 to 1.5% Mn, 8 to 13% Cr, 1.8 to 3.0% W, 0.05 to 0.30% V, 0.02 to 0.12% Nb, 0.02 to 0.05% N, 0.02 to 0.4% Mo, and up to 0.25% Si. This pipe or tube has an improved high-temperature creep rupture strength and an excellent weldability and toughness.

Abstract: A high-Al heat resistant steel comprising a base steel containing not more than 0.7% C, not more than 3.0% Si, not more than 2.0% Mn, 10 to 40% Ni, 9 to 30% Cr, 2 to 8% Al, with balance being Fe and unavoidable impurities, and an Al coating formed on the base steel. The Al coating diffuses into the base steel to form an intermediate Al alloyed layer during the Al coating or by heating after the coating, which alloyed layer prevents the Al coating from spalling, thus providing excellent resistance to oxidation, corrosion, carburization, nitrization and sulphurdization at elevated temperatures.

Abstract: In a continuous annealing furnace, a steel strip is conveyed by conventional hearth rolls made of heat-resistant cast steel, such as HK 40. However, since the formation of buildup is frequent, conventional hearth rolls are inappropriate for long-term operation of a continuous annealing furnace. In the hearth roll of the present invention, which consists of a solid or hollow roll body and a surface layer, the surface layer containing more than 15% by weight of Nb and the balance being inorganic material, the formation of buildup is not frequest, thereby making long-term operation of a continuous annealing furnace possible.

Abstract: A boiler tube having improved high temperature strength, improved high temperature corrosion resistance, and resistivity to embrittlement during the service thereof, comprising an outer surface layer and an inner part, the outer surface layer consisting essentially, by weight, of 0.03-0.20% carbon, 1.5-4.0% silicon, 0.1-3.0% manganese, 13-25% chromium, 13-40% nickel, 0.5-3.0% at least one kind selected from the group consisting of molybdenum and tungsten, 0.05-0.5% at least one kind selected from the group consisting of titanium, niobium and vanadium, and the balance iron and inevitable impurities, the inner part consisting essentially, by weight, of 0.03-0.20% carbon, 0.3-1.0% silicon, 0.1-3.0% manganese, 13-25% chromium, 13-40% nickel, 0.5-3.0% at least one kind selected from the group consisting of molybdenum and tungsten, 0.05-0.5% at least one kind selected from the group consisting of titanium, niobium and vanadium, and the balance iron and inevitable impurities. Boron of 0.001-0.

Abstract: A ferritic heat-resisting steel with an excellent toughness comprises0.03 to 0.10% by weight of carbon,0.1 to 1.0% by weight of silicon,1.5% by weight or less of manganese,1.5% to 2.7% by weight of molybdenum,7.0% to 10.0% by weight of chromium,0.01 to 0.1% by weight of niobium,0.02 to 0.12% by weight of vanadium,0.01 to 0.10% by weight of alloying element consisting of at least one member selected from the group consisting of rare earth elements having atomic numbers 57 through 71 and yttrium, andthe balance consisting of iron and unavoidable impurities, in which steel the ratio of the sum of the numbers of niobium and vanadium atoms to the number of carbon atoms is in the range of from 0.35 to 0.80; and the quantity (Cr%/30+Mo%/10-C%) and the content in percent of said alloying element fall on or within an irregular pentagon indicated in FIG.

Abstract: A stainless steel pipe having a surface layer with excellent resistance against vanadium pentoxide attack experienced upon boiler heating tubes for power generation, corrosion by sulfates, corrosion by chlorides experienced upon boiler heating tubes for various burning furnace and high-temperature gas corrosion experienced upon tubes for heating furnaces in the chemical industry, and also relates to methods for forming the surface layer.

Abstract: A free cutting graphitic steel comprising:Si: from more than 1.5 to 2.3%Mn: 0.1 to 0.7%S: not more than 0.015%One or both Al and Ti: 0.015 to 0.1% in totalRare earth: 0.01 to 0.2% andSpheroidized graphite: 0.20 to 0.90% with the balance being iron and unavoidable impurities,Said spheroidized graphite being distributed at a ratio of more than particles 50/mm.sup.2.