How to calculate the density of an alloy

                                                                                                                     

                                                 Dr. Ron Lasky

Say you want to calculate the density of an alloy of 60% by weight tin (Sn) and 40% lead (Pb). The density of tin is Dsn = 7.29 g/cc and that of lead Dpb = 11.34 g/cc. Let's say you make a 100 g sample of this alloy, 60 g will be Sn, 40 g will be Pb. The total volume of the alloy will be 60 g Sn/Dsn + 40 g Pb/Dpb = 60/7.29 + 40/11.34 = 8.23 cc + 3.53 cc = 11.76 cc. The density of the alloy is its mass (100g) divided by its volume (11.76 cc) or 100/11.76 g/cc = 8.50 g/cc.

In general then, the equation to calculate density is 1/Dalloy = Mass Fraction Metal 1/Dmetal 1 + Mass Fraction Metal 2/Dmetal 2. The equations continues for metals 3, 4 etc.

To facilate the calculation , we provide in the following link an Excel file to do that

https://drive.google.com/open?id=0B-QmTukdEFfQX21nTU9PYUduaXM


Reference:

http://www.indium.com/blog/interest-in-formula-for-calculating-alloy-density-still-keen.php