Abstract: A cast AFA alloy composition comprising, in weight percent: 0.4 to 0.59 Nb+Ta; 0.4 to 0.6 C; 16 to 18 Cr; 18-23 Ni; 3.5-5.5 Al; 0.005 to 0.15 B; up to 1.5 Mo; up to 2 Co; up to 1 W; up to 3 Cu; up to 4 Mn; up to 2 Si; up to 0.5 wt. % total of at least one element selected from the group consisting of Ti and V; up to 0.06 N; up to 1 wt. % total of at least one element selected from the group consisting of Y, La, Ce, Hf, and Zr; balance Fe, wherein the weight percent Fe is greater than the weight percent Ni, and wherein the alloy forms an external continuous scale comprising alumina to at least 900° C. in air with 10% H2O, and a stable essentially single-phase FCC austenitic matrix microstructure, the austenitic matrix being essentially delta-ferrite free and essentially BCC-phase-free, with creep rupture life in excess of 500 h at 900° C. and 50 MPa.

Abstract: A fastener for use in joining dissimilar materials manufactured by the process of producing the fastener with an external surface that forms an electrically insulating oxide layer when subjected to oxidation and, after manufacture and prior to use, subjecting the fastener to a pre-oxidation process to grow the desired oxide layer in situ on the external surface of the fastener. The present invention also provides a dissimilar material joint in which the pre-oxidized fastener is used to mechanically join dissimilar materials with the oxide layer electrically insulating the fastener from at least one of the dissimilar materials. The fastener may be a rivet used in friction self-piercing riveting (F-SPR). The fastener may be fabricated from an alloy capable of forming Al2O3 or Cr2O3 by thermal oxidation. The fastener may be pre-coated with Al or Cr that functions as a seed layer to form Al2O3 or Cr2O3.

Abstract: An austenitic Ni-base alloy, consisting essentially of, in weight percent: 2.5 to 4.75 Al; 21 to 26 Cr; 20 to 40 Fe; 0.75 to 2.5 total of at least one element elected from the group consisting of Nb and Ta; 0 to 0.25 Ti; 0.09 to 1.5 Si; 0 to 0.5 V; 0 to 2 Mn; 0 to 3 Cu; 0 to 2 of at least one element selected from the group consisting of Mo and W; 0 to 1 of at least one element selected from the group consisting of Zr and Hf; 0 to 0.15 Y; 0.3 to 0.55 C; 0.005 to 0.1 B; 0 to 0.05 P; less than 0.06 N and balance Ni (30 to 46 Ni), wherein the weight percent Ni is greater than the weight percent Fe, and wherein the ratio Ni/(Fe+2*C) is between 1.02 and 1.067.

Abstract: A fastener for use in joining dissimilar materials manufactured by the process of producing the fastener with an external surface that forms an electrically insulating oxide layer when subjected to oxidation and, after manufacture and prior to use, subjecting the fastener to a pre-oxidation process to grow the desired oxide layer in situ on the external surface of the fastener. The present invention also provides a dissimilar material joint in which the pre-oxidized fastener is used to mechanically join dissimilar materials with the oxide layer electrically insulating the fastener from at least one of the dissimilar materials. The fastener may be a rivet used in friction self-piercing riveting (F-SPR). The fastener may be fabricated from an alloy capable of forming Al2O3 or Cr2O3 by thermal oxidation. The fastener may be pre-coated with Al or Cr that functions as a seed layer to form Al2O3 or Cr2O3.

Abstract: An austenitic Ni-base alloy includes, in weight percent: 2.5 to 4.75 Al; 13 to 21 Cr; 20 to 40 Fe; 2 to 5 total of at least one element selected from the group consisting of Nb and Ta; 0.25 to 4.5 Ti; 0.09 to 1.5 Si; 0 to 0.5 V; 0 to 2 Mn; 0 to 3 Cu; 0 to 2 of Mo and W; 0 to 1 of Zr and Hf; 0 to 0.15 Y; 0.01 to 0.45 C; 0.005 to 0.1 B; 0 to 0.05 P; less than 0.06 N; and balance Ni (38 to 46 Ni). The weight percent Ni is greater than the weight percent Fe. An external continuous scale comprises alumina. A stable phase FCC austenitic matrix microstructure is essentially delta-ferrite-free, and contains one or more carbides and coherent precipitates of ?? and exhibits creep rupture life of at least 100 h at 900° C. and 50 MPa.

Abstract: An austenitic Ni-base alloy, consisting essentially of, in weight percent: 2.5 to 4.75 Al; 21 to 26 Cr; 20 to 40 Fe; 0.75 to 2.5 total of at least one element elected from the group consisting of Nb and Ta; 0 to 0.25 Ti; 0.09 to 1.5 Si; 0 to 0.5 V; 0 to 2 Mn; 0 to 3 Cu; 0 to 2 of at least one element selected from the group consisting of Mo and W; 0 to 1 of at least one element selected from the group consisting of Zr and Hf; 0 to 0.15 Y; 0.3 to 0.55 C; 0.005 to 0.1 B; 0 to 0.05 P; less than 0.06 N and balance Ni (30 to 46 Ni), wherein the weight percent Ni is greater than the weight percent Fe, wherein the ratio Ni/(Fe+2*C) is between 0.95 and 1.0735, with a scale comprising alumina, a stable phase FCC austenitic matrix microstructure, carbide strengthening phases, and with a creep rupture lifetime of at least 100 h at 900° C. and 50 MPa.

Abstract: An austenitic Ni-base alloy includes, in weight percent: 2.5 to 4.75 Al; 13 to 21 Cr; 20 to 40 Fe; 2 to 5 total of at least one element selected from the group consisting of Nb and Ta; 0.25 to 4.5 Ti; 0.09 to 1.5 Si; 0 to 0.5 V; 0 to 2 Mn; 0 to 3 Cu; 0 to 2 of Mo and W; 0 to 1 of Zr and Hf; 0 to 0.15 Y; 0.01 to 0.45 C; 0.005 to 0.1 B; 0 to 0.05 P; less than 0.06 N; and balance Ni (38 to 46 Ni). The weight percent Ni is greater than the weight percent Fe. An external continuous scale comprises alumina. A stable phase FCC austenitic matrix microstructure is essentially delta-ferrite-free, and contains one or more carbides and coherent precipitates of ?? and exhibits creep rupture life of at least 100 h at 900° C. and 50 MPa.

Abstract: A fastener for use in joining dissimilar materials manufactured by the process of producing the fastener with an external surface that forms an electrically insulating oxide layer when subjected to oxidation and, after manufacture and prior to use, subjecting the fastener to a pre-oxidation process to grow the desired oxide layer in situ on the external surface of the fastener. The present invention also provides a dissimilar material joint in which the pre-oxidized fastener is used to mechanically join dissimilar materials with the oxide layer electrically insulating the fastener from at least one of the dissimilar materials. The fastener may be a rivet used in friction self-piercing riveting (F-SPR). The fastener may be fabricated from an alloy capable of forming Al2O3 or Cr2O3 by thermal oxidation. The fastener may be pre-coated with Al or Cr that functions as a seed layer to form Al2O3 or Cr2O3.

Abstract: The disclosure describes techniques for forming nanoparticles including Fe16N2 phase. In some examples, the nanoparticles may be formed by first forming nanoparticles including iron, nitrogen, and at least one of carbon or boron. The carbon or boron may be incorporated into the nanoparticles such that the iron, nitrogen, and at least one of carbon or boron are mixed. Alternatively, the at least one of carbon or boron may be coated on a surface of a nanoparticle including iron and nitrogen. The nanoparticle including iron, nitrogen, and at least one of carbon or boron then may be annealed to form at least one phase domain including at least one of Fe16N2, Fe16(NB)2, Fe16(NC)2, or Fe16(NCB)2.

Abstract: An improved method for preventing corrosion of magnesium is provided. The method includes providing a magnesium substrate including a native surface layer of nanoporous MgO and Mg(OH)2. The method includes generating a CO2 plasma at atmospheric pressure, flowing the CO2 plasma from a nozzle exit as a plasma plume, and exposing the surface film to the plasma plume. The method further includes reacting activated CO2 gas molecules with the native surface layer by performing an atmospheric CO2 plasma treatment at room temperature to convert at least a portion of the native surface layer of nanoporous MgO and Mg(OH)2 into a nano-structured to micro-structured MgO/MgCO3 coating.

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: An alloy includes in weight % based upon the total weight of the alloy: 28-35% Cr; 2.5-4% Al; 0.8-2% Nb; 5.5-7.5% W; 0-0.5% Mo; 0-0.3% Ti; 0.1-0.3% Zr; 0.1-1% Si; 0-0.07% Y; 0-2% Mn; 0-1% Ni; 0-0.05% C; 0-0.015% B; 0-0.02% N; 0.02-0.04 Ce; balance Fe. The alloy includes a recrystallized, equi-axed grain structure, and forms an external alumina scale, and has strengthening particles including Fe2M (M: Nb, W, Mo, and Ti) type C14 Laves-phase, and a BCC ferritic matrix microstructure from room temperature to melting point with less than 1% FCC-phase, less than 1% martensite phase, less than 0.5 wt. % of carbides (MC and M23C6), and at least 1% tensile elongation at room temperature. The alloy provides a creep resistance of greater than 3000 to 15000 h creep rupture life at 750° C. and 50 MPa, or greater than 500 to 5000 h creep rupture life at 700° C. and 100 MPa.

Abstract: An alloy includes in weight % based upon the total weight of the alloy: 28-35% Cr; 2.5-4% Al; 0.8-2% Nb; 5.5-7.5% W; 0-0.5% Mo; 0-0.3% Ti; 0.1-0.3% Zr; 0.1-1% Si; 0-0.07% Y; 0-2% Mn; 0-1% Ni; 0-0.05% C; 0-0.015% B; 0-0.02% N; 0.02-0.04 Ce; balance Fe. The alloy includes a recrystallized, equi-axed grain structure, and forms an external alumina scale, and has strengthening particles including Fe2M (M: Nb, W, Mo, and Ti) type C14 Laves-phase, and a BCC ferritic matrix microstructure from room temperature to melting point with less than 1% FCC-phase, less than 1% martensite phase, less than 0.5 wt. % of carbides (MC and M23C6), and at least 1% tensile elongation at room temperature. The alloy provides a creep resistance of greater than 3000 to 15000 h creep rupture life at 750° C. and 50 MPa, or greater than 500 to 5000 h creep rupture life at 700° C. and 100 MPa.

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: The disclosure describes a method of producing iron nitride magnets using Zn-doped iron oxide precursors. The iron oxide precursors are reduced and nitrided to produce a powder containing iron nitride in the Fe16N2 phase. The inclusion of Zn in the iron oxide precursor enhances the magnetic properties of the iron nitride powder.

Abstract: A method may include annealing a material including iron and nitrogen in the presence of an applied magnetic field to form at least one Fe16N2 phase domain. The applied magnetic field may have a strength of at least about 0.2 Tesla (T).

Abstract: The method provides heat-resistant chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloys having improved creep resistance. A precursor is provided containing preselected constituents of a chromia- or alumina-forming Fe-, Fe(Ni), Ni(Fe), or Ni-based alloy, at least one of the constituents for forming a nanoscale precipitate MaXb where M is Cr, Nb, Ti, V, Zr, or Hf, individually and in combination, and X is C, N, O, B, individually and in combination, a=1 to 23 and b=1 to 6. The precursor is annealed at a temperature of 1000-1500° C. for 1-48 h in the presence of a magnetic field of at least 5 Tesla to enhance supersaturation of the MaXb constituents in the annealed precursor. This forms nanoscale MaXb precipitates for improved creep resistance when the alloy is used at service temperatures of 500-1000° C. Alloys having improved creep resistance are also disclosed.

Abstract: A combustion chamber, having an upper part and a lower part, may include an annular constriction, in combination with the combustion chamber, to aid in directing partially combusted gases such as carbon monoxide away from the periphery of the combustion chamber back toward its center, and into the flame front. The annular constriction may also impede the flow of partially combusted gases located at the periphery, thus increasing the time these gases spend within the combustion chamber and increasing the likelihood that any products of incomplete combustion will undergo combustion. The combustion chamber may further comprise a dual burner cooktop for directing combustion gases and exhaust to multiple cooking vessels. In further embodiments, the combustion chamber may be made of, lined, or clad with a metal alloy comprising iron, chromium, and aluminum.