You can measure the bulk and apparent densities and also the open porosity of the samples using the Archimedes’ technique with water as the immersing medium.

The relative density is obtainable with respect to the theoretical density.

The theoretical density is estimable using the rule of mixtures, based on starting compositions of the samples and following pure component densities.

You can measure the bulk and apparent densities and also the open porosity of the samples using the Archimedes’ technique with water as the immersing medium.

The relative density is obtainable with respect to the theoretical density.

The theoretical density is estimable using the rule of mixtures, based on starting compositions of the samples and following pure component densities.

Dear Mr.Mohammed,

You can calculate the porosity and density of a sample after firing according to ASTM C 373 for ceramics or by Archimedes’ technique. while before firing, you can calculated them from the geometric dimensions, applied load ,weight of the sample and the area of the used die. may be you can find porosity before firing by using this equation..please try it..

porosity % = 100  - the density of the green body / theoretical density of the required material *100  = .......

see the attachment for calculation of the density of the green body.

ASTM B962 - 14

Standard Test Methods for Density of Compacted or Sintered Powder Metallurgy (PM) Products Using Archimedes’ Principle

You can use mercury porosimetry as long as your metal does not react with mercury, but even in the case, where it might react, you could form a coating on your sample surface to reduce or prevent that reaction.

The advantage of mercury porosimetry is that you do not only get the density information, but you will also get information about the size of your pores and how they change during sintering.

Dear All,

Actually

I have developed five compositions using powder metallurgy and reinforments in increasing weight percentages were added to the  base matrix. And the density of the compacts from base matrix to the final reinforced sample is in decreasing order which also indicates that porosity is in increasing order. Finally , the results are to be justified with respect to the increasing pattern of porosity and I am having difficulty in finding porosity because of limited resources. If any one could help me out as to how to reflect the relative increase in porosity, I would be obliged.

Thanks

Density of fabricated samples will be measured by Archimedes principle. The weight of sample will be taken in air and in a fluid medium with known value of density. By putting the values of these parameters in following equation, the density of the sample can be measured:

Actual density of the sample =  [m/ (m-M)] p , where m and M are the masses of samples in air and water respectively and p is the density of water.  

Further, the theoretical density for the samples will be calculated by the rule of mixtures. The level of porosity (%) can be estimated from the theoretical and actual densities.

Hello everyone!!

My question is how can we measure porosity in casting products. I have studied X-ray CT and SEM methods. but what other methods can be used to measure and examine porosity as casting defect.??

Hello Faisal

You need to specify the type of defect in more detail.

Is it just a couple of pores (bubbles)?

How many per what sample size?

What size range?

Where are they located (surface or in the bulk)?

etc.

Can the theoretical density be found the depending variables?? such as pressure , temperature, hold time??

Dear all,

Can anyone suggest how to measure the theoretical density of the pellet.

And also suggest Archimedes principle for measure the pellet density?

Thanks in advance.

Theoretical density can be calculated by formula Th.Density - summation of (number of moles* Molecular wt of element) / Avagadro number * Unit cell vol. calculated from XRD)

Pellet density can be measured using density = (dry wt/(soaked weight -suspended wt))* Density of water or kerosene ( which ever is used).

Article A deformation-processed Al-matrix/Ca-nanofilamentary composi...

hello everyone

How can I calculate the porosity percentage and relative density of lattice structures?