The densification phenomenon during sintering in the presence of small amount of liquid, with iron and 13%Cr steel powder added Fe-Ti alloy or Fe-Si alloy powder, was investigated. The results obtained are as follows;
1) The densification during sintering in the presence of small amount of liquid is influenced by the sintering characteristics of matrix powder and the amount of liquid.
2) Liquid phase sintering by the addition of Fe-Ti alloy and Fe-Si alloy effective for the densification of compact and the strengthening of matrix.

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The effect of porosity of green compact on the densification during the sintering of 13 CrMoTi Steel powder added Fe-Ti alloy powder was investigated. The result obtained are as follow;
In the liquid phase sintering, when the amount of liquid phase is small, the shrinkage of green compact is proportional to the porosity, and the relation between the relative sintered density, ρs, and fractional porosity, s is represented by the following equation.
?? (k is constant 0≤k≤1)

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Microscopic observations of the intragranular pores were carried out to clarify the factors which determine the shape of pores during sintering in variously heat treated Cu-and Ni-ferrites.
For prolonged annealing at the temperature range in which no change in pore size was observed, pores which consisted of (111) planes and curved surfaces were observed. The formation of such a poreshape is considered to be caused by minimization of surface free energy. At annealing temperature where the pore size changed, the pore under growing were apt to form the octahedral shape, but pores under shrinking formed the spherical shape. In the case of samples oxidized at lower temperatures, unsymmetrical pores which consisted of (111) planes on the surface and of spherical surfaces in the interior sides of samples were observed. In samples slowly cooled from temperatures above the solidus temperatures, the polyhedral pores having not only (111) planes but also (100), (110), (311) and (331) planes were observed. It is suggested that there exist some other factors than the surface free energy, which determine the shape of pores in actual sintered bodies.

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Li-Mn-Zn-ferrite (Li0.33 Mn0.42 Zn0.20 Fe2.05 O4+δ) was heat-treated at various temperatures between 450 and 1200°C, and the changes of cation valence, crystal lattice constant and oxygen content in the ferrite by this heat-treatment were measured. The oxygen and Mn3+ ion contents in the ferrite decreased with increasing temperature, while the crystal lattice constant increased. The stoichiometric ferrite (δ=0) was obtained by heat-treating at about 900°C in oxygen and air, and at about 700°C in nitrogen.
The relationship between the crystal lattice constant a0 and an oxygen content deviation from the stoichiometry δ, was found to be as follows:
a0=8.371-0.37δ forδ>0
a0=8.371-0.37δ forδ>0.

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