A nickel-chromium-iron-aluminum alloy contains (in wt. %)>17 to 33% chromium, 1.8 to <4.0% aluminum, 0.10 to 15.0% iron, 0.001 to 0.50% silicon, 0.001 to 2.0% manganese, 0.00 to 0.60% titanium, 0.0002 to 0.05% each of magnesium and/or calcium, 0.005 to 0.12% carbon, 0.001 to 0.050% nitrogen, 0.0001 to 0.020% oxygen, 0.001 to 0.030% phosphorus, not more than 0.010% sulfur, not more than 2.0% molybdenum, not more than 2.0% tungsten, the remainder nickel with nickel ≥50% and the usual process-related impurities, for use in solar power tower plants using nitrate salt melts as the heat transfer medium, wherein the following relations must be satisfied: Fp≤39.9 (2a) with Fp=Cr+0.272*Fe+2.36*Al+2.22*Si+2.48*Ti+0.374*Mo+0.538*W−11.8*C (3a), wherein Cr, Fe, Al, Si, Ti, Mo, W and C is the concentration of the respective elements in % by weight.

A nickel-chromium-aluminum alloy includes (in mass %) 12 to 30% chromium, 1.8 to 4.0% aluminum, 0.1 to 7.0% iron, 0.001 to 0.50% silicon, 0.001 to 2.0% manganese, 0.00 to 1.00% titanium, 0.00 to 1.10% niobium, 0.00 to 0.5% copper, 0.00 to 5.00% cobalt, in each case 0.0002 to 0.05% magnesium and/or calcium, 0.001 to 0.12% carbon, 0.001 to 0.050% nitrogen, 0.001 to 0.030% phosphorus, 0.0001 to 0.020% oxygen, max. 0.010% sulfur, max. 2.0% molybdenum, max. 2.0% tungsten, and a remainder of nickel with a minimum content of 50% and the usual process-related impurities for use in solar power towers, using chloride and/or carbonate salt melts as a heat transfer medium, wherein in order to ensure a good processability, the following condition must be met: F.sub.V 0.9 with F.sub.V=4.88050−0.095546*Fe−0.0178784*Cr−0.992452*Al−1.51498*Ti−0.506893*Nb+0.0426004*Al*Fe, where Fe, Cr, Al, Ti, and Nb are the concentration of the respective elements in mass %.

The present disclosure provides a high-strength and high-plasticity casting high-entropy alloy (HEA), having a general formula of Al.sub.aCo.sub.bCr.sub.cTi.sub.dFe.sub.eNi.sub.fCu.sub.g, where 6.0<a≤8.0, 18.0<b≤23.0, 7.5≤c<12.5, 2.0<d≤8.5, 15.5<e≤20.0, 28.0<f≤37.0, 0.2<g≤10.0, and a+b+c+d+e+f+g=100. The casting HEA can be prepared in one step and has excellent mechanical properties. The various metal raw materials are environmental-friendly and suitable for large-scale industrial production.

Disclosed is a Ni—Cr-based brazing alloy including, on the basis of mass %: 15%<Cr<30%; 3%<P<12%; 0%≤Si<8%; 0.01%<C<0.06%; 0%≤Ti+Zr<0.1%; 0.01%<V<0.1%; 0%≤Al<0.01%; 0.005%<O<0.025%; 0.001%<N<0.050%; 0%≤Nb<0.1%; and the balance being Ni and incidental impurities. Inequality (1): 0.2≤0.24V %/C %≤1.0 is satisfied if the alloy contains no Nb, and Inequality (2): 0.2≤(0.24V %+0.13Nb %)/C %≤1.0 is satisfied if the alloy contains Nb. Also disclosed is an inexpensive Ni—Cr-based brazing alloy containing a trace amount of V for use in the production of stainless steel heat exchangers and other steel articles. The alloy has a low liquidus temperature and high corrosion resistance, and achieves high brazing strength.

A high melt superalloy powder mixture is provided for use with additive manufacturing or welding metal components or portions thereof. The high melt superalloy powder may include by weight about 7.7% to about 18% chromium, about 10.6% to about 11% cobalt, about 4.5% to about 6.5% aluminum, about 10.6% to about 11% tungsten, about 0.3% to about 0.55% molybdenum, about 0.05% to about 0.08% carbon, and at least 40% nickel.

The present invention relates to alloys used to prepare steel pipes i.e. tubes for use in chemical engineering applications. In particular, the invention relates to low carbon aluminium steel alloys and pipes made from such alloys. They may be used in plant such as ethylene cracker furnaces that need to be able to withstand elevated temperatures oxidation and carburisation for extended periods of time, the alloy been able to develop a pure, stable and continuous aluminium oxide layer on it surface when in service which is protective and anti-coking

A nickel-niobium intermetallic alloy contains, in weight percent, silicon from about 1.5 to about 3.5 percent; chromium from 5 to about 15 percent; nickel from about 45 to about 75 percent; niobium from about 14 to about 30 percent; cobalt up to about 7 percent; and iron up to about 10 percent; wherein the nickel plus niobium content is about 70 to about 90 percent and the total silicon, chromium, cobalt and iron content is about 10 to about 30 percent. The alloy can have a cast microstructure of at least 95 volume percent intermetallic phases and no more than about 5 volume percent solid solution phases. The intermetallic phases can include rod-like intermetallic phases of Ni.sub.3Nb and Ni.sub.8Nb.sub.7. The microstructure can be a lamellar microstructure and/or the microstructure can have less than 5 volume percent Ni—Fe and Ni—Co rich intermetallic phases.

Methods and compositions are provided for improving metal dusting corrosion, abrasion resistance and/or erosion resistance for various materials, preferably for applications relating to high-temperature reactors, including dense fluidized bed reactor components. In particular, cermets comprising (a) at least one ceramic phase selected from the group consisting of metal carbides, metal nitrides, metal borides, metal oxides, metal carbonitrides, and mixtures of thereof and (b) at least one metal alloy binder phase are provided. Ceramic phase materials include chromium carbide (Cr.sub.23C.sub.6). Metal alloy binder phase materials include β-NiAl intermetallic alloys and Ni.sub.3Sn.sub.2 intermetallic alloys, as well as alloys that contain α-Cr and/or γ′-Ni.sub.3Al hard phases. Preferably, bimetallic materials are provided when the cermet compositions are applied using a laser, e.g., a laser cladding method such as high power direct diode (HPDD) laser, or by plasma-based methods such as plasma transfer arc (PTA) welding and powder plasma welding (PPW).

Ni—Mn—Si based braze filler alloys or metals which may be nickel-rich, manganese-rich, or silicon-rich braze filler alloys, have unexpectedly narrow melting temperature ranges, low solidus and low liquidus temperatures, as determined by Differential Scanning calorimetry (DSC), while exhibiting good wetting, and spreading, without deleterious significant boride formation into the base metal, and can be brazed at lower temperatures. The nickel rich alloys contain 58 wt % to 70 wt % nickel, the manganese-rich alloys contain 55 wt % to 62 wt % manganese, and the silicon-rich alloys contain 25 wt % to 29 wt % silicon. Copper with or without boron to partly replace nickel may be employed without any substantial increase of the melting point, or to reduce the melting point. The braze filler alloys have sufficient brazability to withstand high temperature conditions for thin-walled aeronautical and other heat exchangers.

An embodiment relates to an ultrasonic additive manufacturing process, comprising joining a foil comprising a bulk metallic glass to a substrate; and forming a cladded composite comprising the foil and the substrate; wherein a thickness of the cladded composite is greater than a critical casting thickness of the bulk metallic glass, wherein the cladded composite comprises a cladding layer of the bulk metallic glass on the substrate and the bulk metallic glass comprises approximately 0% crystallinity, approximately 0% porosity, less than 50 MPa thermal stress, approximately 0% distortion, approximately 0 inch heat affected zone, approximately 0% dilution, and a strength of about 2,000-3,500 MPa.