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.

The present invention provides a Co-free heat-resistant alloy for a hearth metal member that has properties superior to or equal to those of Co-containing heat resistant steel. The heat-resistant alloy for a hearth metal member according to the present invention is a heat-resistant alloy used in a hearth metal member of a steel heating furnace, the heat resistant alloy containing: 0.05% to 0.5% of C; more than 0% and 0.95% or less of Si, where 0.05%≤C+Si≤1.0%; more than 0% and 1.0% or less of Mn; 40% to 50% of Ni; 25% to 35% of Cr; 1.0% to 3.0% of W; and 10% or more of Fe and inevitable impurities as the balance, with all percentages being in mass %. The heat-resistant alloy for a hearth metal member may further contain 0.05% to 0.5% of Ti and/or 0.02% to 1.0% of Zr, with all percentages being in mass %.

A nickel-chromium-aluminum alloy as powder is used for additive manufacturing, wherein the powder consists of spherical particles of a size of 5 to 250 pm, and wherein this alloy consists of (in % by weight) 24 to 33% chromium, 1.8 to 4.0% aluminum, 0.10 to 7.0% iron, 0.001 to 0.50% silicon, 0.005 to 2.0% manganese, 0.00 to 0.60% titanium, 0.0 to 0.05% magnesium and/or calcium respectively, 0.005 to 0.12% carbon, 0.001 to 0.050% nitrogen, 0.00001-0.100% oxygen, 0.001 to 0.030% phosphorus, a maximum of 0.010% sulfur, a maximum of 2.0% molybdenum, a maximum of 2.0% tungsten, the remainder nickel and the usual process-related impurities, wherein, with a pore size >1 pm, the powder has total inclusions of 0.0-4% of the pore surface area.

An environmentally resistant alloy is disclosed having a transition metal that upon being included in the Ni Cr Al alloy causes no liquid phases below 1310° C., creates over 45% of a gamma phase above 900° C. up to 1310° C., creates over 30% comprised of a gamma prime phase between 450° C. and 600° C., and wherein the gamma prime phase is characterized by a formula (Ni,Co).sub.x(Cr,Al,Mo).sub.y wherein x and y are integers.

The invention relates to an austenitic alloy comprising the following elements in weight %: C 0.03; Si 1.0; 5 Mn 1.5; S 0.03; P 0.03; Cr 25.0 to 33.0; Ni 42.0 to 52.0; 10 Mo 6.0 to 9.0; N 0.07-0.11; Cu 0.4; Balance Fe and unavoidable impurities; and characterized in that the austenitic alloy fulfills the following condition: E.sub.Ni>1.864*E.sub.Cr19.92 wherein E.sub.Cr=[wt % Cr]+[wt % Mo]+1.5*[wt % Si] and E.sub.Ni=[wt % Ni]+30*[wt % C]+30*[wt % N]+0.5*[wt % Mn]+0.5*[wt % Cu]. The invention also relates to a manufacturing method and an object comprising said alloy. The alloy and objects made thereof have less than 0.3% intermetallic phases after solidification.

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.

The present invention provides an alloy for overlay welding with which an alumina barrier layer containing an Al oxide can be formed on a projection that is overlay welded on an inner surface of a reaction tube, and a reaction tube having a projection that is overlay welded on the inner surface as a stirring member.

An alloy for overlay welding according to the present invention is an alloy for overlay welding that is to be used in overlay welding, and the alloy contains C in an amount of 0.2 mass % to 0.6 mass %, Si in an amount of more than 0 mass % to 1.0 mass %, Mn in an amount of more than 0 mass % to 0.6 mass % or less, Cr in an amount of 25 mass % to 35 mass %, Ni in an amount of 35 mass % to 50 mass %, Nb in an amount of 0.5 mass % to 2.0 mass %, Al in an amount of 3.0 mass % to 6.0 mass %, Yin an amount of 0.005 mass % to 0.05 mass %, wherein Y/Al is 0.002 or more to 0.015 or less; and the balance being Fe and inevitable impurities.

Disclosed herein are embodiments of a nickel-based alloy. In particular embodiments, the nickel-based alloy is configured for use in applications involving supercritical fluids. The disclosed nickel-based alloy embodiments are highly resistant to corrosion and exhibit high stability and thus are suited for use in vessels, boilers, piping, and other receptacles that contain or are used with supercritical fluids. Method embodiments of making the nickel-based alloy also are disclosed.

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.

Disclosed herein are embodiments of a nickel-based alloy. In particular embodiments, the nickel-based alloy is configured for use in applications involving supercritical fluids. The disclosed nickel-based alloy embodiments are highly resistant to corrosion and exhibit high stability and thus are suited for use in vessels, boilers, piping, and other receptacles that contain or are used with supercritical fluids. Method embodiments of making the nickel-based alloy also are disclosed.