Some variations provide a method of making an additively manufactured single-crystal metallic component, comprising: providing a feedstock comprising a first metal or metal alloy; providing a build plate comprising a single crystal of a second metal or metal alloy; exposing the feedstock to an energy source for melting the feedstock, generating a melt layer on the build plate; and solidifying the melt layer, generating a solid layer (on the build plate) of a metal component. The solid layer is also a single crystal of the first metal or metal alloy. The method may be repeated many times to build the part. Some variations provide a single-crystal metallic component comprising a plurality of solid layers in an additive-manufacturing build direction, wherein the plurality of solid layers forms a single crystal of a metal or metal alloy with a continuous crystallographic texture. The crystal orientation may vary along the additive-manufacturing build direction.

A device including a templating structure and a magnetic layer on the templating structure is described. The templating structure includes D and E. A ratio of D to E is represented by D.sub.1-xE.sub.x, with x being at least 0.4 and not more than 0.6. E includes a main constituent. The main constituent includes at least one of Al, Ga, and Ge. Further, E includes at least fifty atomic percent of the main constituent. D includes at least one constituent that includes Ir, D includes at least 50 atomic percent of the at least one constituent. The templating structure is nonmagnetic at room temperature. The magnetic layer includes at least one of a Heusler compound and an L1.sub.0 compound, the magnetic layer being in contact with the templating structure.

A device including a templating structure and a magnetic layer on the templating structure is described. The templating structure includes D and E. A ratio of D to E is represented by D.sub.1-xE.sub.x, with x being at least 0.4 and not more than 0.6. E includes a main constituent. The main constituent includes at least one of Al, Ga, and Ge. Further, E includes at least fifty atomic percent of the main constituent. D includes at least one constituent that includes Ir, D includes at least 50 atomic percent of the at least one constituent. The templating structure is nonmagnetic at room temperature. The magnetic layer includes at least one of a Heusler compound and an L1.sub.0 compound, the magnetic layer being in contact with the templating structure.

The disclosure relates to a method for making an iron telluride including placing Fe, Bi, and Te in a reacting chamber as reacting materials. The reacting chamber is evacuated to be a vacuum with a pressure lower than 10 Pa. The reacting chamber is heated to a first temperature of 700 degrees Celsius to 900 degrees Celsius and keeping the first temperature for a period of 10 hours to 14 hours. Then the reacting chamber is cooled to a second temperature of 400 degrees Celsius to 700 degrees Celsius within 60 hours to 75 hours and keeping the second temperature for a period of 40 hours to 50 hours, to obtain a reaction product including a FeTe.sub.0.9 single crystal. The FeTe.sub.0.9 single crystal is separated from the reaction product.

The disclosure relates to a method for making an iron telluride including placing Fe, Bi, and Te in a reacting chamber as reacting materials. The reacting chamber is evacuated to be a vacuum with a pressure lower than 10 Pa. The reacting chamber is heated to a first temperature of 700 degrees Celsius to 900 degrees Celsius and keeping the first temperature for a period of 10 hours to 14 hours. Then the reacting chamber is cooled to a second temperature of 400 degrees Celsius to 700 degrees Celsius within 60 hours to 75 hours and keeping the second temperature for a period of 40 hours to 50 hours, to obtain a reaction product including a FeTe.sub.0.9 single crystal. The FeTe.sub.0.9 single crystal is separated from the reaction product.

A casting method includes forming a seed. The seed has a first end and a second end. The forming includes bending a seed precursor. The seed second end is placed in contact or spaced facing relation a chill plate. The first end is contacted with molten material. The molten material is cooled and solidifies so that a crystalline structure of the seed propagates into the solidifying material. The forming further includes inserting the bent seed precursor into a sleeve leaving the bent seed precursor protruding from a first end of the sleeve.

A casting method includes forming a seed. The seed has a first end and a second end. The forming includes bending a seed precursor. The seed second end is placed in contact or spaced facing relation a chill plate. The first end is contacted with molten material. The molten material is cooled and solidifies so that a crystalline structure of the seed propagates into the solidifying material. The forming further includes inserting the bent seed precursor into a sleeve leaving the bent seed precursor protruding from a first end of the sleeve.

A method of making a component includes: depositing a metallic powder on a workplane; directing a beam from a directed energy source to fuse the powder in a pattern corresponding to a cross-sectional layer of the component; repeating in a cycle the steps of depositing and fusing to build up the component in a layer-by layer fashion; and during the cycle of depositing and melting, using an external heat control apparatus separate from the directed energy source to maintain a predetermined temperature profile of the component, such that the resulting component has a directionally-solidified or single-crystal microstructure.

A method of making a component includes: depositing a metallic powder on a workplane; directing a beam from a directed energy source to fuse the powder in a pattern corresponding to a cross-sectional layer of the component; repeating in a cycle the steps of depositing and fusing to build up the component in a layer-by layer fashion; and during the cycle of depositing and melting, using an external heat control apparatus separate from the directed energy source to maintain a predetermined temperature profile of the component, such that the resulting component has a directionally-solidified or single-crystal microstructure.

A manufacturing method includes: (1) providing M-M′ nanowires, wherein M′ is at least one sacrificial metal different from M; and (2) subjecting the M-M′ nanowires to electrochemical de-alloying to form jagged M nanowires.