Need help to calculate VOl fraction 2

[alavi419]

Hi every body
I have an elementary question because i am confusing now.
I should prepare different mixtures of powders for sintering. the instruction gave me the fraction of element in mass percent but i want to have one of the compund in the mixture in Vol%. let me to write one of the mixture here:
Fe-0.8Wt%C-0.15Wt%B this is the mixture that I want to add 10 vol& of tungstencarbide. how can I calculate the amount of each constituent in gram?
i will be appreciated if some body can help me.
Thanks in advance

 

[CoryPad]

Why do you need to use volume? Measuring powder mass is easy, while measuring powder volume is much less easy. If you think you need volume because of composites calculations like Rule of Mixtures, then just use the mass versions of those.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Compositepro]

It is a pretty basic calculation but it can get confusing. Obviously, weight% and volume% are related by the component densities. The trick is to assume in your calculation that you start with one gram or one cc of mixture (depending on which way you are converting). If you know weight% then you know how many grams of each component are in the mixture. The density of each component is used to convert to volume. So then you know the volume of each component and the total volume of the mixture. This is all you need to know to calculate volume%.
This can be reduced to an equation but I never bother to memorize it. It helps to reduce errors when you understand what you are doing.

 

[CoryPad]

What Compositepro wrote is true for components that don't react/diffuse/etc. If you are mixing elemental B, C & Fe with the compound WC, you need a more complex calculation because the B, C & Fe form compounds (not know a priori) with varying densities. Best to go with mass.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.