Provided is a copper alloy containing 18% by mass to 30% by mass of Zn, 1% by mass to 1.5% by mass of Ni, 0.2% by mass to 1% by mass of Sn, and 0.003% by mass to 0.06% by mass of P, the remainder including Cu and unavoidable impurities. Relationships of 17f1=[Zn]+5[Sn]2[Ni]30, 14f2=[Zn]0.5[Sn]3[Ni]26, 8f3={f1(32f1)}.sup.1/2[Ni]23, 1.3[Ni]+[Sn]2.4, 1.5[Ni]/[Sn]5.5, and 20[Ni]/[P]400 are satisfied. The copper alloy has a metallographic structure of an single phase.

A mold assembly for use in forming a component having an internal passage defined therein is provided. The component is formed from a component material. The mold assembly includes a mold that defines a mold cavity therein. The mold assembly also includes a lattice structure selectively positioned at least partially within the mold cavity. The lattice structure is formed from a first material that has a selectively altered composition in at least one region of the lattice structure. A channel is defined through the lattice structure, and a core is positioned in the channel such that at least a portion of the core extends within the mold cavity and defines the internal passage when the component is formed in the mold assembly.

A titanium slab is appropriate for hot rolling, is produced by electron beam melting furnace, has superior linearity so that it can be fed into a hot rolling machine without performing breaking down process or other subsequent correcting process after production, and has good structure having no cracks at the corner parts. A process for production thereof is also provided. The titanium slab is directly produced by a mold of an electron beam melting furnace, and has the deformation of not more than 5 mm for the thickness direction versus the longitudinal direction and deformation of not more than 2.5 mm for the width direction versus the longitudinal direction, both per a length of 1000 mm of the slab. The process for production of this titanium slab for hot rolling has a step of using an electron beam melting furnace in which its rectangular mold has mold walls of a long side and mold walls of a short side, and a step of pouring molten metal from one of the mold walls of a short side. Furthermore, a mold having chamfered parts at the corner parts can be used in the process.

A method of making an article includes placing a high thermal conductive insert in a mold. A liquid metal composition is introduced into the mold into contact with the high thermal conductive insert. The liquid metal composition in the mold is solidified to form a solid metal article with the high thermal conductive insert retained therein, and the solid metal article with the high thermal conductive insert retained therein is removed from the mold.

A coinage alloy for coinage includes nickel present in an amount from 4 wt. % to 11 wt. %, based on a total weight of the coinage alloy; zinc present in an amount from 20 wt. % to 35 wt. %, based on the total weight of the coinage alloy; manganese present in an amount from 3 wt. % to 6 wt. %, based on a total weight of the coinage alloy; copper; an electrical conductivity from 5% International Annealed Copper Standard (IACS) to 6% IACS measured in accordance with ASTM E1004-09 (2009); and a color comprising a yellowness vector b* that is from 6 to 11, based on a CIE L*a*b* color space and determined in accordance with ASTM Standard E308-15 (2015).

A coinage alloy for coinage includes nickel present in an amount from 13 wt. % to 16 wt. %, based on a total weight of the coinage alloy; zinc present in an amount from 25 wt. % to 32 wt. %, based on the total weight of the coinage alloy; manganese present in an amount from 1 wt. % to 4 wt. %, based on a total weight of the coinage alloy; copper; an electrical conductivity from 5% International Annealed Copper Standard (IACS) to 6% IACS; and a color comprising a yellowness vector b* that is from 5 to 10, based on a CIE L*a*b* color space and determined in accordance with ASTM Standard E308-15 (2015).

A light metal material having a tensile strength of >180 MPa at room temperature is provided, as well as a method for producing such a light metal material and the use of such a light metal material as a piston component in a rotary piston engine.

A coinage cladding alloy for coinage includes nickel present in an amount from 5 wt. % to 7 wt. %, based on a total weight of the coinage cladding alloy; zinc present in an amount from 21 wt. % to 29 wt. %, based on the total weight of the coinage cladding alloy; manganese present in an amount from 12 wt. % to 16 wt. %, based on a total weight of the coinage cladding alloy; copper; an electrical conductivity from 2% International Annealed Copper Standard (IACS) to 3% IACS; and a color comprising a yellowness vector b* that is from 2 to 10, based on a CIE L*a*b* color space and determined in accordance with ASTM Standard E308-15 (2015).

The present invention provides a method for casting a slab having a good cast surface. The method includes heating the surface of molten metal on a metal inlet side of a mold by a first heat source so that the following formulas: q0.87 and c11.762q+0.3095 are satisfied where c is a cycle time [sec] of turning movement of the first heat source, and q is an average amount of heat input [MW/m.sup.2] determined by accumulating an amount of heat input applied by at least the first heat source to the contact region between the upper surface of the slab on the metal inlet side and the mold, along the path of turning movement of the first heat source, and dividing the resultant accumulated value by the cycle time c.

A system (5) and method (800) for unit cell casting of titanium or titanium-alloys is disclosed herein. The system (5) comprises an external chamber (45), a crucible (10) positioned within the external chamber (45), an induction coil (15) positioned around the crucible, an internal chamber (40) positioned within the external chamber (45), and a mold (30) positioned within the internal chamber (40). The external chamber (45) is evacuated and a pressurized gas is injected into the evacuated external chamber (45) to create a pressurized external chamber (45). An ingot (20) is melted within the crucible utilizing induction heating generated by the induction coil (15). The internal chamber (40) is evacuated to create an evacuated internal chamber (40). The titanium alloy material of the ingot (20) is completely transferred into the mold (30) from the crucible (10) using a pressure differential created between the external chamber (45) and the internal chamber (40).