Chapter 15, Problem 15.16P

Interpretation Introduction

(a)

Interpretation:

The apparent porosity needs to be determined.

Concept Introduction:

The apparent porosity is the percentage of the total volume of the ceramic that is occupied by interconnected pores. Interconnected pores are those that provide channels through which gases and fluids can flow. It is also known as the measure of the permeability, or the ease with which gases and fluids seep throughthe ceramic components.

Interpretation Introduction

(b)

Interpretation:

The true porosity needs to be determined.

Concept Introduction:

In the polycrystalline ceramics, pores are most important defects. The pores results in the decrease in the mechanical strength of bulky ceramics. This is because due to presence of pores, cracks can grow in the ceramics. Under the tensile load, the brittle behavior of ceramics is due to the presence of these pores.

Interpretation Introduction

(c)

Interpretation:

The value of closed porosity needs to be determined.

Concept Introduction:

The fraction of volume occupied by the fluid in the poers network is known as open porosity. The non- interconnected noids in the solid phase that are not included in the open porosity are known as closed porosity. The thermalized pores can collide with the pore walls and results in the shortening of the lifetime.