Abstract: A method of manufacturing a 3D object, the method comprising: providing a powder layer of powder particles; building up a new layer of the 3D object by directing a beam of radiation towards the powder layer to melt the powder particles at predetermined positions to build up the new layer of the 3D object on re-solidification; and forming a pore in the new layer at a preselected position by using a beam of radiation to form and subsequently collapse a melt pool so as to trap gas as a pore in or below the new layer at the preselected position on re-solidification.

Abstract: A nickel-based alloy composition consisting, in weight percent, of: 1.5 to 4.5% aluminium, 1.1 to 3.4% titanium, 0.0 to 4.0% niobium, 0.0 to 5.2% tantalum, 0.9 to 6.6% tungsten, 0.0 to 3.0% molybdenum, 0.0 to 24.0% cobalt, 12.5 to 20.6% chromium, 0.02 to 0.15% carbon, 0.001 to 0.015% boron, 0.0 to 0.1% zirconium, 0.0 to 3.0% rhenium, 0.0 to 2.0% ruthenium, 0.0 to 3.0% iridium, 0.0 to 0.5% vanadium, 0.0 to 1.0% palladium, 0.0 to 1.0% platinum, 0.0 to 0.5% silicon, 0.0 to 0.1% yttrium, 0.0 to 0.1% lanthanum, 0.0 to 0.1% cerium, 0.0 to 0.003% sulphur, 0.0 to 0.25% manganese, 0.0 to 0.1 magnesium, 0.0 to 5.0% iron, 0.0 to 0.5% copper, 0.0 to 1.0% hafnium, the balance being nickel and incidental impurities, wherein the following equations are satisfied in which WAl, WTi, WNb, WTa and WW are the weight percent of aluminium, titanium, niobium, tantalum and tungsten in the alloy respectively 0.65?0.3 WNb+0.15 W 3.6?WAl+0.5 WTi+0.3 WNb+0.15 WTa?5.7 WTa+0.92WW?6.1.

Abstract: A nickel-based alloy composition consisting, in weight percent, of: between 1.0 and 3.5% aluminium, 0.0 and 3.6% titanium, 0.0 and 6.0% niobium, 0.0 and 4.9% tantalum, 0.0 and 5.4% tungsten, 0.0 and 4.0% molybdenum, 8.9 and 30.0% cobalt, 10.8 and 20.6% chromium, 0.02 and 0.35% carbon, between 0.001 and 0.2% boron, between 0.001 and 0.5% zirconium, 0.0 and 5.0% rhenium, 0.0 and 8.5% ruthenium, 0.0 and 4.6 percent iridium, between 0.0 and 0.5% vanadium, between 0.0 and 1.0% palladium, between 0.0 and 1.0% platinum, between 0.0 and 0.5% silicon, between 0.0 and 0.1% yttrium, between 0.0 and 0.1% lanthanum, between 0.0 and 0.1% cerium, between 0.0 and 0.003% sulphur, between 0.0 and 0.25% manganese, between 0.0 and 6.0% iron, between 0.0 and 0.5% copper, between 0.0 and 0.

Abstract: A nickel-based alloy composition consisting, in weight percent, of: 4.0 to 5.6% aluminium, 0.0 to 1.0% titanium, 0.0 to 4.0% niobium, 0.0 to 11.9% tantalum, 2.0 to 12.7% tungsten, 0.0 to 3.0% molybdenum, 0.0 to 22.0% cobalt, 6.0 to 16.7% chromium, 0.02 to 0.35% carbon, 0.001 to 0.2% boron, 0.00 to 0.5% zirconium, 0.0 to 3.0% rhenium, 0.0 to 2.0% ruthenium, 0.0 to 3.0% iridium, 0.0 to 0.5% vanadium, 0.0 to 1.0% palladium, 0.0 to 1.0% platinum, 0.0 to 0.5% silicon, 0.0 to 0.1% yttrium, 0.0 to 0.1% lanthanum, 0.0 to 0.1% cerium, 0.0 to 0.003% sulphur, 0.0 to 0.25% manganese, 0.0 to 0.1 magnesium, 0.0 to 4.0% iron, 0.0 to 0.5% copper, 0.0 to 1.0% hafnium, the balance being nickel and incidental impurities, wherein the following equations are satisfied in which WNb, and WTa are the weight percent of niobium and tantalum respectively 1.1?0.3WNb+0.15WTa.

Abstract: Generating tool path data for an additive manufacturing apparatus comprises providing object design data in which at least a part of a physical object is represented by a line. A section of the line is then sliced using an intermediate slicing layer that is provided between first and second physical build layers of the additive manufacturing apparatus. The slicing generates an intermediate layer point at the intersection of the section of the line and the intermediate slicing layer, with the intermediate layer point being located between the first and second physical build layers. The intermediate layer point is then projected to a projected build layer point that lies within a physical build layer of the additive manufacturing apparatus. The projected build layer point is used to provide tool path data for that physical build layer. A similar process can be used in which the physical object is represented by a surface.

Abstract: A titanium-based alloy composition consisting in weight percent, of: 3.0 to 7.0% aluminium, 3.0 to 10.0% vanadium, 3.0 to 10.0% molybdenum, 2.0 to 7.0% tin, 0.0 to 6.0% zirconium, 0.0 to 5.0% niobium, 0.0 to 0.5% iron, 0.0 to 4.0% chromium, 0.0 to 2.0 tungsten, 0.0 to 0.5 % nickel, 0.0 to 0.5% tantalum, or between 0.0 to 2. tantalum when the sum of niobium and tantalum is 5.0% or less, 0.0 to 0.5% cobalt, 0.0 to 0.75% silicon, 0.0 to 0.5% boron, 0.0 to 0.5% carbon, 0.0 to 0.5% oxygen, 0.0 to 0.5% hydrogen, 0.0 to 0.5% nitrogen, 0.0 to 0.5% palladium, 0.0 to 0.5% lanthanum, 0.0 to 0.5% manganese or 0.0 to 2.5% manganese when the sum of chromium and manganese is 4.0 wt. % or less, 0.0 to 1.0% hafnium, the balance being titanium and incidental impurities which satisfies the following relationship: 0.027V+0.178Fe+0.055(Mo+0.5W)+0.016Zr+0.044Cr+0.033(Nb+Ta)+0.053Sn>1.

Abstract: Generating tool path data for use in additive manufacturing comprises providing object design data in which at least part of the object is represented abstractly using lines and/or surfaces. The lines and/or surfaces can then be used to provide tool path data for the build layers of an additive manufacturing apparatus. The tool paths can be reconfigured to reduce the overall distance travelled and/or travel time when the additive manufacturing apparatus implements the tool path data. An additive manufacturing parameter for a structural feature of the object can also be selected based on the geometry of the structural feature and specified in the tool path data.

Abstract: A nickel-based alloy composition consisting, in weight percent, of: between 5.0% and 6.9% aluminium, between 0.0% and 11.0% cobalt, between 6.0% and 11.6% chromium, between 0.0% and 4.0% molybdenum, between 0.0% and 2.0% niobium, between 0.6 and 8.6% tantalum, between 0.0% and 3.0% titanium, between 8.4% and 15.2% tungsten, between 0.02 wt. % and 0.35 wt. % carbon, between 0.001 and 0.2 wt. % boron, between 0.001 wt. % and 0.5 wt. %. zirconium, between 0.0 and 0.5% silicon, between 0.0 and 0.1% yttrium, between 0.0 and 0.1% lanthanum, between 0.0 and 0.1% cerium, between 0.0 and 0.003% sulphur, between 0.0 and 0.25% manganese, between 0.0 and 0.5% copper, between 0.0 and 2.0% hafnium, between 0.0 and 1.0% vanadium, between 0.0 and 4.0% iron, between 0.0 and 1.

Abstract: A nickel-based alloy composition consisting, in weight percent, of: between 1.0 and 3.5% aluminium, 0.0 and 3.6% titanium, 0.0 and 6.0% niobium, 0.0 and 4.9% tantalum, 0.0 and 5.4% tungsten, 0.0 and 4.0% molybdenum, 8.9 and 30.0% cobalt, 10.8 and 20.6% chromium, 0.02 and 0.35% carbon, between 0.001 and 0.2% boron, between 0.001 and 0.5% zirconium, 0.0 and 5.0% rhenium, 0.0 and 8.5% ruthenium, 0.0 and 4.6 percent iridium, between 0.0 and 0.5% vanadium, between 0.0 and 1.0% palladium, between 0.0 and 1.0% platinum, between 0.0 and 0.5% silicon, between 0.0 and 0.1% yttrium, between 0.0 and 0.1% lanthanum, between 0.0 and 0.1% cerium, between 0.0 and 0.003% sulphur, between 0.0 and 0.25% manganese, between 0.0 and 6.0% iron, between 0.0 and 0.5% copper, between 0.0 and 0.

Abstract: Generating tool path data for an additive manufacturing apparatus comprises providing object design data in which at least a part of a physical object is represented by a line. A section of the line is then sliced using an intermediate slicing layer that is provided between first and second physical build layers of the additive manufacturing apparatus. The slicing generates an intermediate layer point at the intersection of the section of the line and the intermediate slicing layer, with the intermediate layer point being located between the first and second physical build layers. The intermediate layer point is then projected to a projected build layer point that lies within a physical build layer of the additive manufacturing apparatus. The projected build layer point is used to provide tool path data for that physical build layer. A similar process can be used in which the physical object is represented by a surface.