Course: CL-232

Porosity Measurement (Materials)

Faculty: Prof. Jayesh Bellare TA’s :Amit Patil Swathi

Objectives

To determine Apparent porosity of refractory materials using ”The Boiling Water Method”

To determine True specific gravity of material

Theory The Boiling Water method

Apparent porosity :Relation between the volume of a mass and the volume of the water absorbed when the mass is immersed.

= Open pore volume/ Bulk volume

True Porosity :The sum of open pores as determined by water absorptions plus the volume of those pores which are sealed by vitreous matter and therefore closed to water

= Total pore Volume/ Bulk volume

Total bulk volume = Open pore volume + Closed pore volume+ Volume of material.

Apparent Porosity

D (Dry weight of specimen )S (Suspended weight )

W (Saturated Weight )

Specific Gravity

W1 (weight of Pycnometer) W2 (weight of Pycnometer+ Sample )

W4 (wt of Pycnometer+ Sample+ water ) W3 (wt of Pycnometer+ Sample+kerosene)

Role of porosity Thermal conductivity Permeability Surface properties Thermal resistance of the body Corrosion

Sample Calculation

Apparent porosity (P)% =

Specific Gravity =

100SW

DW

)()( 2314

12

WWWW

WW