Abstract: A novel CVD method for preparing a layer including refractory carbide crystals, silicon carbide crystals, wherein at least part of the layer is formed from a gas mixture containing a silicon source and an aromatic carbon source, wherein the molar C/Si ratio in said gas mixture is from about 0.85 to about 1.45. Also, layers obtainable by the method and their various uses and applications.

Abstract: A refractory carbide multilayer including a first layer, a second layer and a third layer. The first layer has an average thickness of at least 25 nm and contains at least one refractory carbide, the second layer has an average thickness of at least 25 nm and contains at least one refractory carbide, the third layer has an average thickness of at least 25 nm and contains at least one refractory carbide, and the first layer has a larger mean linear intercept section grain size than the second layer.

Abstract: Herein a boiler tube (2) having a longitudinal extension (L) and comprising radially inner and outer tubular portions (4, 6) extending along at least a first part (5) of the longitudinal extension (L). The radially outer tubular portion (6) is metallurgically bonded to the radially inner tubular portion (4). A sensor space (8) is arranged between the radially inner tubular portion (4) and the radially outer tubular portion (6), wherein the sensor space (8) is configured to accommodate a sensor arranged to detect a physical property of the radially outer tubular portion (6). A duct (10) is connected to the sensor space (8) and extends through the radially outer tubular portion (6) to an exit portion (12) of a surface of the radially outer tubular portion (6). The radially inner and outer tubular portions comprise materials of different chemical composition. Also, a boiler tube unit and a furnace are disclosed herein.

Abstract: An austenitic alloy comprising (in weight %): C: 0.01-0.05 Si: 0.05-0.80 Mn: 1.5-2 Cr: 26-34.5 Ni: 30-35 Mo: 3-4 Cu: 0.5-1.5 N: 0.05-0.15 V: ?0.15 the balance being Fe and unavoidable impurities, characterized in that 40?% Ni+100*% N?50.

Abstract: An austenitic alloy comprising (in weight %): C: 0.01-0.05 Si: 0.05-0.80 Mn: 1.5-2 Cr: 26-34.5 Ni: 30-35 Mo: 3-4 Cu: 0.5-1.5 N: 0.05-0.15 V: ?0.15 the balance being Fe and unavoidable impurities, characterized in that 40?% Ni+100*% N?5 50.

Abstract: An austenitic alloy comprising (in weight %): C: 0.01-0.05 Si: 0.05-0.80 Mn: 1.5-2 Cr: 26-34.5 Ni: 30-35 Mo: 3-4 Cu: 0.5-1.5 N: 0.05-0.15 V: <0.15 the balance being Fe and unavoidable impurities, wherein 40<% Ni+100*% N<50.

Abstract: An austenitic alloy comprising (in weight %): C: 0.01-0.05 Si: 0.05-0.80 Mn: 1.5-2 Cr: 26-34.5 Ni: 30-35 Mo: 3-4 Cu: 0.5-1.5 N: 0.05-0.15 V: <0.15 the balance being Fe and unavoidable impurities, wherein 40<% Ni+100*% N<50.

Abstract: A compound tube including a layer of a Fe—Cr alloy and a layer of load-carrying component, with the optional addition of further layers. The Fe—Cr alloy preferably has a composition including, in weight-%: less than 0.3% carbon, 15-60% chromium, less than 10% nickel, less than 5% molybdenum, less than 5% silicon, less than 0.3% nitrogen, less than 5% manganese, and the remainder iron with naturally occurring impurities. The compound tubes are very resistant to carbonization and metal dusting, and are suited for use as bayonet tubing, superheater tubing, and reforming tubing in steam formation environments.

Abstract: A compound tube comprises a layer of a Fe—Cr—Al-alloy and a layer of a load-carrying component and optionally one or several additional layers. The Fe—Cr—Al-alloy has the following analysis in weight-%: carbon<0.3, chromium 5-30, nickel<10, manganese<5, molybdenum<5, aluminium 3-20 , silicon<5, nitrogen<0.3, cerium+bafnium+yttrium<1.0, titanium 0.005-1.0, zirconium 0.005-1.0, niobium 0.005-1.0, the remainder iron, and naturally occurring impurities. These tubes are very resistant towards carbonization and “metal dusting” and are being used to advantage for bayonet tubing, superheat tubing and reformer tubing in steam formation.

Abstract: As tube material in waste incineration it has been found advantageous to use a composite tube wherein an inner tube component of a carbon steel or a low-alloy Cr—Mo-steel is metallurgically bonded to an outer tube component of Ni—Cr—Mo—Nb—Fe-alloy with an austenitic structure. The composite tube is fabricated by spraying finely distributed metal drops of the outer component onto the inner component in melt condition. After solidifying, the composite tube is then fabricated by joint extrusion.