Density Computation For Ceramics

Ceramic density computation a c a v n n a a c σ σ ρ number of formula units unit cell volume of unit cell n number of cations in unit cell ac atomic weight of cation na number of anions in unit cell aa atomic weight of anion vc volume of unit cell na avogadro s number.

Density computation for ceramics. We use the equation c a fe o c a c a v n n a a v n n a a ρ since the crystal structure is rock salt n 4 formula units per unit cell and. This problem features the density formula for ceramics. However it is important to pay special attention to the units used for density calculations. Melting points high 600 4000c thermal conductivities are low insulators thermal expansion values are low 1 15 ppm c 3.

The theoretical density of the materials of the anode cathode and electrolyte are used to calculate the porosity of the materials a critical parameter in determining if the fuel cell will function properly. The calculation of density is quite straightforward. Density calculations in ceramic structures c a c a v n n a a ρ n number of formula units in unit cell all ions that are included in the chemical formula of the compound formula unit σσσσac sum of atomic weights of cationsin the formula unit σσσσaa sum of atomic weights of anions in the formula unit vc volume of the unit cell. Materials science problem that calculates the number of chemical sio2 units per unit cell of silicon dioxide.

Mole sc2o3 0 92 mole hfo2 1 03 mole ceo2 1 4. It is possible to access the bulk density of a porous ceramic sample by the archimedes method either by immersing a coated sample in a wetting liquid. Or by immersing the uncoated sample in a non. Lectures 22 and 23 introduction to ceramics ceramic density calculations example.

There are many different ways to express density and not using or converting into the proper units will result in an incorrect value. First you shall have to determine the bulk density using the formula. Mass volume and then determine the theoretical density from xrd data using. Mole tio2 86 58 mole zro2.

Zm nv where z is the number of atom per unit.