CHRONICLES

THIRD ALL-UNION CONFERENCE ON DIFFUSION

IN METALS AND ALLOYS

M. A~ Krishtal and A. P. Mokrov

The third All-Union conference on diffusion in metals and alloys was held in June, 1968, at the Tula Po[ytechnicai Institute, Over 250 delegates from 20 cities of the Soviet Union attended. Ninety reports were given, concerning the theory and mechanism of diffusion, diffusion in multicomponent systems, and techniques.

Considerable attention was given to the theory of diffusion. M. A. Krishtal, B. Ya. Lybov, Ya. E. Geguzin, K, P. Gurov, and V. T. Borisov gave an analysis of the current state of diffusion theory and the course of further research. Particular attention was given to the atomic diffusion mechanism and the in- terpretation and calculation of diffusion parameters based on concepts of modeling. This is a significant contribution to the development and further improvement of the phenomenological and microscopic theories of diffus ion.

Ya. E. Geguzin and I. M. Lifshits showed the importance of the diffusion mechanism in healing of pores. L. V. Pavlinov, A. M. Gladyshev, and V. I. Bykov presented new data on the diffusion of low- solubility impurities in magnesium and calcium, while L. V. Pavlinov proposed a mechanism for themove- ment of atoms of these impurities. The possibility of a diffusion mechanism during phase transformations was reported by K. P. Gurov and V. V, Shmidt. These same authors presented a mathematical model of diffusion for the cubic system. R. A. Andrievskii and K. P. Gurov analyzed the possible mechanisms of selfdiffusion of carbon in carbides of transition metals within the scope of the hole gas technique. The theoretical conclusions were compared with experimental data. K. P. Gurov, analyzing Darken's theory, showed that Darken's equation can be obtained only under conditions where flows of a nondiffusion nature can be excluded. In a moving system of coordinates the form of Darken's equation is retained, but an addition- al component appears, the presence of which limits the diffusion annealing time. M. A. Krishtal, V. I. Strelkov, A. P. Mkorov, and B. A. Filonenko gave a more detailed description of the processes occurring in the diffusion zone in multilayer samples with inert markers. M. A. Krishtal, V. I. Strelkov, I. A. Goncharenko, Ya. E. Geguzin, Yu. I. Boiko, et al., gave new data on the formation and distribution of structural defects (vacancies and dislocations) in the diffusion zone during the diffusion process.

Of great interest was a lively discussion of reviews by V. M. Golikov, Ya. E. Geguzin, S. M. Klots- man, and A. N. Timofeev, in which a critical analysis was given of the current state of structural defects in diffusion and the latest experiments were noted.

Other reports were also given concerning dislocations (I. L. Mirkin, A. P. Mokr0v, and V. N. Vodop'yanov; M. A. Krishtal, A. P. Mokrov, M. A. Viboishchik, and S. A. Golovin; V. A. Panteleev, M. A. Matosyan, and V. M. Golikov), grain boundaries (P. L. Gruzin, Yu. D. Zharov, S. V. Zemskii, I. K. Kupalova, Ya. E. Geguzin, E. R. Dobrovinskaya, M. A. Krishtal, I. A. Goncharenko, O. V. Stepanova, V. N. Kaigorodov, S. M. Klotsman, A. N. Timofeev, et al,), and crystal surfaces (Ya. E. Geguzin, Yu. S. Koganovskii, I. V. Stoichev, V. T. Borisov, V. V. Gal', P. L. Gruzin, et al.).

For the first time considerable attention was given to diffusion in multicomponent systems (G. V. Sheherbedinskii, M. A. Krishtal). A great many reports concerned the thermodynamics and kinetics of diffusion in ternary systems (G. V. Shcherbedinskii, V. I. Shaidurov, M. A. Krishtal, A. P. Mokrov, Yu. I. Davydov, V. D. Korvachev, L. V. Rogova, V. P. Bulychev, V. D. Korvachev, A. A. Zhukov, R. L. Snezhnoi, and Yu. S. Sokolov).

There were also reports concerning the role of diffusion in phase transformations (L. N. Larikov, V. F. Fal'chenko, et al.), during irradiation of metals and alloys (L. I. Bystrov, L. I. Ivanov, Yu. M. Platov, V. A. Shalashov, V. V. Komissarov, I. A. Maiinenko, O. N. Shivrin, et al.), and the concentra- tion dependence of diffusion coefficients in binary and other systems (I. D. Marchukova, O. I. Tikhomirova, I. A. Pikunov, L. P. Ruzinov, I. D. Marchukova, Yu. ]~. Ugast~, G. B. Fedorov, E. A. Smirnov, F. I. Zhomov, et al).

Trans la t ed f rom Metal lovedenie i T e r m i c h e s k a y a Obrabotka Metallov, No. 3, pp. 75-76, March, 1969

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Methods of studying diffusion in metals and alloys were described in reviews by P. L. Gruzin, Yu. D. Zharov, S. Y. Zemskii, Yu. A. Po[ikarpov, A. P. Mokrov and also reports by L. M. Shcherbakov, Yu. B. Zakharov, O. I. Korolev, I. Sh. Trakhtenberg, et al.

A considerable number of reports concerned the importance of diffusion in processes of failure (L. I. Mirkin), oxidation (V. V. Latsh, L. F. Sokiryanskii, S. S. Mozhaev, V. T. Maksimova, and I. F. Khar- tamov), purification (S. V. Zemskii, V, P. Lyakhin), diffusion metallizing (E. P. Ponomarenko, A. A. Domio, and V. P. Khokhlov), and other practical problems (S. A. Golovanenko, S. B. Maslenkov, I. Yu. Konnova, A. Ya. Shinyaev, I. N. Voropai, V. A. Matveev, L. M. Shcherbakov, A. V. Smirnov, V. M. Perverzev, et al.).

Most of the reports were printed and distributed at the beginning of the conference, which facilitated the proceedings and permitted more productive discussions.

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