На широком круге металлов и сплавов исследованы возникновение и вре-менная эволюция упорядоченных в пространстве картин локализации пла-стической деформации -волн. Установлены основные характеристики этих волн: зависимость скорости распространения от коэффициента деформаци-онного упрочнения, закон дисперсии, зависимости длины волны от размеров зерен и размера образцов. Рассмотрена возможность описания локализации пластического течения как процесса самоорганизации в деформируемой среде. Получены уравнения, необходимые для описания эволюции очагов локализации пластического течения. Проанализирован переход между кар-тинами локализации деформации на разных стадиях пластического течения. Предложена модель для объяснения крупномасштабной периодичности в распределении очагов локализации деформации.На широкому колі металів і сплавів досліджено виникнення і часова еволюція впорядкованих у просторі картин локалізації пластичної деформації -хвиль. Встановлено основні характеристики цих хвиль: залежність швидкості поши-рення від коефіцієнту деформаційного зміцнення, закон дисперсії, залежності довжини хвилі від розмірів зерен і розміру зразків. Розглянуто можливість опи-су локалізації пластичної течії як процесу самоорганізації в середовищі, що деформується. Отримано рівняння, необхідні для опису еволюції осередків локалізації пластичної течії. Проаналізовано перехід між картинами локаліза-ції деформації на різних стадіях пластичної течії. Запропоновано модель для пояснення великомасштабної періодичності в розподілі осередків локалізації деформації.The initiation of spatially-ordered strain-localization patterns-waves which evolve with time-is investigated for a wide range of the deformed materialsmetals and alloys. The main parameters of these waves, i.e. the propagation velocity against the work-hardening coefficient, dispersion law, and wavelength against the grain size and specimen length are determined. Consideration is Успехи физ. мет. / Usp. Fiz. Met. 2002, т. 3, сс. 237-304 Îòòèñêè äîñòóïíû íåïîñðåäñòâåííî îò èçäàòåëÿ Ôîòîêîïèðîâàíèå ðàçðåøåíî òîëüêî â ñîîòâåòñòâèè ñ ëèöåíçèåé 2002 ÈÌÔ (Èíñòèòóò ìåòàëëîôèçèêè èì. Ã. Â. Êóðäþìîâà ÍÀÍ Óêðàèíû) Íàïå÷àòàíî â Óêðàèíå.

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It is established that granular glass can be obtained as an intermediate product for foam glass crystal materials based on common silica component (marshallite, diatomite, opoka) at temperatures not exceeding 900°C. It is shown that the use of granular glass with glass phase present in amounts greater than 80 wt.% makes it possible to obtain foam crystal glass materials with density up to 250 g/cm 3 .Ecologically safe and fireproof long-lived thermal insulation materials are now of practical interest in the construction industry. Foam glass materials meet all these requirements, but questions concerning expansion of the raw materials base for the production of such materials remain topical. There is a need to develop more readily accessible materials, for example, such as foam crystalline materials, which might be obtainable by a two-stage technology that includes synthesis of granular glass by means of low-temperature treatment of a mix with a certain composition (RF Patent No. 2326841).The objective of our work is to establish the possibility of obtaining granular glass as an intermediate product for foam glass crystalline materials based on common silica components at temperatures not exceeding 900°C.One condition for the formation of melt and a glass phase at relatively low temperatures is high dispersity of the main refractory components of the mix -silica. In a previous work we established that the silica size fraction is less than 100 mm [1]. The use of natural finely dispersed materials will expand the raw materials base for obtaining granular glass, since classic glassmaking is based on quartz sand with particle size 0.1 -0.5 mm. To preserve the chemical uniformity of a finely dispersed mix during heat-treatment and to increase its chemical activity the mix was first densified by rolling in a dish-shaped granulator and a granular glass was obtained in the form of partially fused porous granules [2,3].In addition to a high dispersity of the refractory material, an important condition for synthesis of the granular glass is the composition of the initial mix, which is based on three components: high-silica glass former, alkali (fluxing addition), and alkaline-earth, which affects primarily the viscous properties of the melt. To determine the component composition of the mix, the phase diagrams of the three-component system Na 2 O -CaO -SiO 2 were analyzed and a base composition was chosen for the glass. The concentration range of the glass was determined taking account of the following limiting requirements: the amount of the glass formers in the composition must exhibit high stability with respect to glass formation; the silicon oxides content of the glass must be no lower than 60 and no higher than 75% 4 ; the content of alkali metal oxide should be in the range 13 -22%, for which a glassy state obtains after the melt cools;the prescribed composition of the mix should lie near the boundary lines and eutectics, this corresponds to a lower melting temperature and the highest crystallization power of the me...

The process of plastic deformation in ultrafine grain titanium is considered. Using the methods of speckle photography and X-ray diffractometry, the distributions of local strains and of local elastic distortions were examined for the test sample work. It is shown that the method of atomic-force microscopy can be used effectively for qualitative and quantitative assessment of ultrafine grain material structure.

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