A process for casting a single crystal axis-symmetric thick walled tube comprising forming a axisymmetric single crystal ring seed around a circular internal core, wherein the ring seed has an inner diameter and a taper on the inner diameter, and wherein the internal core has an outer diameter and a matching taper on the outer diameter, the matching taper matching the taper of the inner diameter of the ring seed, and the internal core being free to translate in a vertical direction relative to the ring seed; and heating the ring seed so as to expand the ring seed relative to the internal core, and allowing the circular internal core to translate relative to the ring seed in a direction of the force of gravity, thereby maintaining contact between the circular internal core and the ring seed.

A single-crystalline metal is created on a substrate by liquefying a metal material contained within a crucible while in contact with a surface of the substrate, cooling the metal material by causing a temperature gradient effected in the substrate in a direction that is neutral along the surface of the substrate and, therein, growing the single-crystalline metal in the crucible.

A single-crystalline metal is created on a substrate by liquefying a metal material contained within a crucible while in contact with a surface of the substrate, cooling the metal material by causing a temperature gradient effected in the substrate in a direction that is neutral along the surface of the substrate and, therein, growing the single-crystalline metal in the crucible.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.

A method for casting comprising: providing a seed, the seed characterized by: an arcuate form and a crystalline orientation progressively varying along an arc of the form; providing molten material; and cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material.

A method for casting comprising: providing a seed, the seed characterized by: an arcuate form and a crystalline orientation progressively varying along an arc of the form; providing molten material; and cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material.

A single-crystal diamond, wherein the single-crystal diamond has an average of a phase difference per unit thickness of 10 nm/mm or less, and the phase difference has a standard deviation of 5 nm/mm or less.

A single-crystal diamond, wherein the single-crystal diamond has an average of a phase difference per unit thickness of 10 nm/mm or less, and the phase difference has a standard deviation of 5 nm/mm or less.

A casting method includes forming a seed. The seed has a first end and a second end and an inner diameter (ID) surface and an outer diameter (OD) surface. The seed second end is placed in contact or spaced facing relation with a chill plate. The first end is contacted with molten material. The molten material is cooled and solidified so that a crystalline structure of the seed propagates into the solidifying material. At least a portion of the seed contacted with the molten material has a solidus higher than a solidus of at least an initial pour portion of the molten material.