Density

Micromeritics Accupyc II 1340

Helium pycnometry measures true (absolute) and skeletal (apparent) volume and density.  

These terms are defined as follows:

True (absolute) density = mass
______________________
volume
(excluding open and closed pores)
Skeletal (apparent) density = mass
______________________
volume
(including open and closed pores)

The instrument measures the volume of a material by gas displacement using the volume-pressure relationship of Boyle’s Law.  An inert gas such as helium or nitrogen is used as the displacement medium.  The sample is placed in a sealed cup of a known volume.  This cup is then placed into the sample chamber.  Gas is introduced to the sample chamber and then expanded into a second empty chamber with a known volume.  The pressure observed for filling the sample cell and discharging the gas into the second chamber are measured and then the volume is calculated.  The density is determined by dividing the sample weight by the volume measured. 

Sample Requirements

  • There are three sample cups sizes available for use: 1cc, 3.5 cc and 10 cc.
  • The sample can be a powder or solid but if it is a solid it must fit in the sample cup

Applications

  • Ceramics, powder metallurgy, refractory materials, soil, pharmaceuticals, minerals

To learn more about the Accupyc please contact Katya Bazilevskaya at eab204@psu.edu

To visit the manufacturer’s website for this instrument, visit:

Micromeritics Website

More from Wikipedia: https://en.wikipedia.org/wiki/Gas_pycnometer