COMPRESSION OF LITHIUM FERRITES DURING RADIATION-THERMAL SINTERING

In the work presented here some experimental results are given on sintering of Li-Ti ferrites containing fuse additive Bi2O3 under action of powerful beam accelerated electrons as well as under ordinary thermal conditions. It is shown that all the stages of the processes are intensified under radiation-thermal conditions. The results have been discussed in terms of Ivensen phenomenological theory of sintering. The parameter m of the Ivensen's equation: V = V0(1 - mq-tau)-1/m is described by the expression: m(T) - 7,4.10(-3) exp (0,71 eV/kT) for thermal conditions and m(P-T) = 1,05 exp (0,16 . eV/kT) - for radiation thermal conditions. The parameter q, determined both by initial concentration of defects and pore curing rate, does not vary. Taking into accound the radiation generation of defects with a velocity D the equation (1) can be transformed in the foll following form: V/V0 = [1 + (AN0 - square root DA)tau]-B/A where m - A/B, MQ - AN0. The difference between equation (1) and (2) is that the parameter m remains constant with the variation of parameter mq. Though, there is the constancy of q with the variation of m in experiment. Therefore, the explanation of intensifying action of electron beam due to baking deceleration of material pre-history defects seems reasonable. Nevertheles radiation induced intensifying diffusion especally at deep stages of sintering when structure is played decisive role imperfaction. But at early stages (in particular, in the process of heating) the influence of fuse adding Bi2O3 is the most important.