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Ultrasonic speed in alloys

  1. Oct 29, 2012 #1
    Hi there ,
    I have been trying to work out what the speed of sound is when passing through a metal alloy made out of 91.67% AU and 8.33% CU.
    If anyone here knows,would you care to share, or point me to a place where I can find out ?
    Thank you very much
  2. jcsd
  3. Oct 29, 2012 #2


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    Several sites, e.g., Hypherphysics, have the speed of sound in gold with a value of 3240 m/s. I can't find a consistent value for copper though.

    The speed of sound would be dominated by the gold content.

    If one can find the bulk modulus and density of the mixture then one can apply a forumla to get an approximate value:

    v = √(B/ρ)

    Ref: http://hyperphysics.phy-astr.gsu.edu/hbase/sound/souspe2.html#c1

    One could approximate the density of the mixture using the average determined from the element densities weighted according to atomic fraction.
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