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In metalworking and jewelry making, casting is a process in which a liquid metal is delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a three-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and ...
An aluminium alloy (UK / IUPAC) or aluminum alloy (NA; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further ...
Where t is the solidification time, V is the volume of the casting, A is the surface area of the casting that contacts the mold, n is a constant, [clarification needed] and B is the mold constant. This relationship can be expressed more simply as: = Where the modulus M is the ratio of the casting's volume to its surface area:
Semi-solid metal casting (SSM) is a near net shape variant of die casting. [1] The process is used today with non-ferrous metals, such as aluminium , copper , [ 2 ] and magnesium . It can work with higher temperature alloys that lack suitable die materials.
In aluminium alloys containing magnesium, magnesium oxides (MgO), cuboids (MgAl 2 O 4 -cuboid) and metallurgical spinel (MgAl 2 O 4 -spinel) can form. They result from the reaction between magnesium and oxygen in the melt. More of them will form with time and temperature. Spinel can be highly detrimental because of its big size and high hardness.
Stress corrosion cracking (SCC) is the growth of crack formation in a corrosive environment. It can lead to unexpected and sudden failure of normally ductile metal alloys subjected to a tensile stress, especially at elevated temperature. SCC is highly chemically specific in that certain alloys are likely to undergo SCC only when exposed to a ...
Permanent mold casting. Permanent mold casting is a metal casting process that employs reusable molds ("permanent molds"), usually made from metal. The most common process uses gravity to fill the mold, however gas pressure or a vacuum are also used. A variation on the typical gravity casting process, called slush casting, produces hollow castings.
Direct chill casting. Direct Chill casting is a method for the fabrication of cylindrical or rectangular solid ingots from non-ferrous metals, especially Aluminum, Copper, Magnesium and their alloys. The original ingots are usually further processed by other methods (rolling, forging, etc.). More than half of global aluminum production uses the ...