A NiCrFe-based casting alloy is provided for use in manufacturing a component for contacting molten glass, such as a centrifugal spinner for forming fibers of a molten glass by a rotary fiber forming process, for example. This NiCrFe-based casting alloy is suitable for use in manufacturing a component for contacting molten glass, and contains, in terms of mass percent, 15-30% Cr, 15-30% Fe, 2.5-5.0% Co, 3.0-6.0% W, 0.0-2.0% Ti, 0.5-2.5% Nb, 0.5-2.0% Mo, and 0.5-1.2% C, the remainder including nickel and unavoidable impurities.

To provide a cast product having an alumina barrier layer and method for producing the same. A cast product having an alumina barrier layer of the present invention is a cast product in which an alumina barrier layer containing Al.sub.2O.sub.3 is formed on the surface of a cast body, and the cast body contains C: 0.3 mass % to 0.7 mass %, Si: 0.1 mass % to 1.5 mass %, Mn: 0.1 mass % to 3 mass %, Cr: 15 mass % to 40 mass %, Ni: 20 mass % to 55 mass %, Al: 2 mass % to 4 mass %, rare earth element: 0.005 mass % to 0.4 mass %, W: 0.5 mass % to 5 mass % and/or Mo: 0.1 mass % to 3 mass %, and 25 mass % or more of Fe in the remainder and an inevitable impurity, and 80 mass % or more of the rare earth element is La.

The present invention provides a tube body that is to be used in a high-temperature atmosphere and a method for stably forming a metal oxide layer on an inner surface of the tube body at a high area percentage.

The tube body that is to be used in a high-temperature atmosphere according to the present invention is constituted by a heat-resistant alloy containing Cr in an amount of 15 mass % or more and Ni in an amount of 18 mass % or more, and on the inner surface, an arithmetic average roughness (Sa) of three-dimensional surface roughness satisfies 1.5?Sa?5.0 and a skewness (Ssk) of a surface height distribution satisfies |Ssk|?0.30. The heat-resistant alloy may contain Al in an amount of 2.0 mass % or more. On the inner surface, a kurtosis (Sku) of a surface height distribution of the three-dimensional surface roughness may satisfy Sku?2.5.

A nickel-chromium casting alloy comprising, in weight percent, up to 0.8% of carbon, up to 1% of silicon, up to 0.2% of manganese, 15 to 40% of chromium, 0.5 to 13% of iron, 1.5 to 7% of aluminum, up to 2.5% of niobium, up to 1.5% of titanium, 0.01 to 0.4% of zirconium, up to 0.06% of nitrogen, up to 12% of cobalt, up to 5% of molybdenum, up to 6% of tungsten and from 0.01 to 0.1% of yttrium, remainder nickel, has a high resistance to carburization and oxidation even at temperatures of over 1130 C. in a carburizing and oxidizing atmosphere, as well as a high thermal stability, in particular creep rupture strength.

A substrate steel of the comprising from 0.01 to 0.60 wt. % of La, from 0.0 to 0.65 wt. % of Ce; from 0.06 to 1.8 wt. % of Nb up to 2.5 wt. % of one or more trace elements and carbon and silicon may be treated in an oxidizing atmosphere to product a coke resistant surface coating of MnCr.sub.2O.sub.4 having a thickness up to 5 microns.

An Ni-based alloy solid wire for welding has a composition comprising specific amounts of Cr, Ti, Nb, C, S, Mn and Fe, where Mo+W, P, Si, Al, Ca, B, Mg, Zr, Co, O, H, and N are controlled to specific amounts, ([Ti]+[Nb])/[C] is 80 to 150, and the balance is Ni and inevitable impurities. [Ti], [Nb], and [C] represent the contents of Ti, Nb, and C (mass %), respectively.

A method of welding using a weld filler additive and a weld filler additive are provided. The method includes the step of welding the component with a filler additive comprising a sufficient amount of each of W, Co, Cr, Al, Ti, Mo, Fe, B, C, Nb, and Ni, the component including a hard-to-weld base alloy. The method further includes the step of forming an easy-to-weld target alloy on a surface of the component from the welding.

A nickel chromium alloy comprising 0.4 to 0.6% carbon, 28 to 33% chromium, 15 to 25% iron, 2 to 6% aluminum, up to 2% silicon, up to 2% manganese, up to 1.5% niobium, up to 1.5% tantalum, up to 1.0% tungsten, up to 1.0% titanium, up to 1.0% zirconium, up to 0.5% yttrium, up to 0.1% nitrogen, and nickel, has a high oxidation and carburization stability, long-term rupture strength and creep resistance. This alloy is particularly suited as a material for components of petrochemical plants and for parts, for example tube coils of cracker and reformer furnaces, pre-heaters, and reformer tubes, as well as for use for parts of iron ore direct reduction plants.

A heterogeneous composition is disclosed, including an alloy mixture and a ceramic additive. The alloy mixture includes a first alloy having a first melting point of at least a first threshold temperature, and a second alloy having a second melting point of less than a second threshold temperature. The second threshold temperature is lower than the first threshold temperature. The first alloy, the second alloy, and the ceramic additive are intermixed with one another as distinct phases. An article is disclosed including a first portion including a material composition, and a second portion including the heterogeneous composition. A method for forming the article is disclosing, including applying the second portion to the first portion.

A nickel-chromium casting alloy comprising, in weight percent, up to 0.8% of carbon, up to 1% of silicon, up to 0.2% of manganese, 15 to 40% of chromium, 0.5 to 13% of iron, 1.5 to 7% of aluminum, up to 2.5% of niobium, up to 1.5% of titanium, 0.01 to 0.4% of zirconium, up to 0.06% of nitrogen, up to 12% of cobalt, up to 5% of molybdenum, up to 6% of tungsten and from 0.01 to 0.1% of yttrium, remainder nickel, has a high resistance to carburization and oxidation even at temperatures of over 1130 C. in a carburizing and oxidizing atmosphere, as well as a high thermal stability, in particular creep rupture strength.