Li ferrite with substitution 2% grow slower than that substituted with 1% under the same preparation condition.
In general, Lifetime τ1 is increased with intragranular porosity due to the decrease of the hopping electrons at B-sites in bulk sample. (PAS) is a good technique that helps to know a qualitative distribution of intragranular and intergranular pores. Also, gives a qualitative distribution of intragranular pores at the walls of the domains and inside them.
The novels of this work for substituted Li ferrite are:
1)
The correlations between the lifetime of positrons and the hopping of the electrons at B- sites.
2)
The correlation between the initial permeability, G.S and relative intensity I1.
3)
The variation in grain growth due to the change of concentration of the substituted ions that affects on lifetime parameters for Li ferrite.