Lo-Ex

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Lo-Ex is an aluminium alloy with a very small thermal expansion co-efficient. It contains approximately 14 per cent silicon, 2 per cent nickel, and 1 per cent each of copper and magnesium. [1]

Applications

It has been used extensively and successfully over the years for all types of piston, [2] including in Hillman Imp, [3] and Terraplane [4] engines.

LM13 is a related alloy in the Lo-Ex series, also widely used for diesel engine pistons. [5] This alloy contains 12% silicon, 1% copper and 1% magnesium. [5] Both of these alloys have also been used in a strengthened form, reinforced by an MMC or hybrid composite of alumina or zirconium ceramic fibres. These alloys have been worked by squeeze casting or stir casting. [5]

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<span class="mw-page-title-main">Magnesium</span> Chemical element, symbol Mg and atomic number 12

Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals it occurs naturally only in combination with other elements and it almost always has an oxidation state of +2. It reacts readily with air to form a thin passivation coating of magnesium oxide that inhibits further corrosion of the metal. The free metal burns with a brilliant-white light. The metal is obtained mainly by electrolysis of magnesium salts obtained from brine. It is less dense than aluminium and is used primarily as a component in strong and lightweight alloys that contain aluminium.

<span class="mw-page-title-main">Metallurgy</span> Field of science that studies the physical and chemical behavior of metals

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<span class="mw-page-title-main">Aluminium alloy</span> Alloy in which aluminium is the predominant metal

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References

  1. Internal combustion engines illustrated. Long Acre, London: Odhams Press Limited. 1947. p. 85.
  2. R. Munro (1978). "Wellworthy get it under control". Industrial Lubrication and Tribology. 30 (6): 224–235. doi:10.1108/eb053170.
  3. "The Imp Engine".
  4. "1936 Terraplane specifications" (PDF).
  5. 1 2 3 Smallman, R.E.; Bishop, Ray J. (1999). Modern Physical Metallurgy and Materials Engineering. Butterworth-Heinemann. p. 370. ISBN   9780750645645.