Mallory metal is proprietary name
MALLORY Alloys Group
for an alloy
An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, ...
of tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolat ...
, with other metallic elements added to improve machining.
Its primary use is as a balance weight which is added to the crankshaft
A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting ...
of an automotive engine, where the existing counterweight is not large enough to compensate for the weight of the reciprocating and rotating components attached to the crankshaft's connecting rod
A connecting rod, also called a 'con rod', is the part of a piston engine which connects the piston to the crankshaft. Together with the crank, the connecting rod converts the reciprocating motion of the piston into the rotation of the cranksh ...
journals.
Rather than add to the counterweight by welding or fabrication, holes are drilled in structurally safe positions in the counterweights, and "slugs" (cylindrical dowels) of Mallory metal are inserted and fastened securely.
The difference in density
Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...
between the replacement Mallory metal and the original steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
is about 2:1, so the counterweight is heavier without changing its shape or size.
Notes
Tungsten alloys
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