1989 Fiscal Year Final Research Report Summary
EFFECTS OF GRAIN BOUNDARIES ON RECRYSTALLIZATION OF BICRYSTALS
| Project/Area Number |
62550476
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Physical properties of metals
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| Research Institution | The University of Tokushima |
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Principal Investigator |
INOKO Fukuji THE UNIVERSITY OF TOKUSHIMA, MECHANICAL ENGINEERING, PROFESSOR, 工学部, 教授 (50029104)
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| Project Period (FY) |
1987 – 1989
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| Keywords | Recrystallization / Grain boundary / Aluminum bicrystal / Copper bicrystal / Deformation bands / Strain induced boundary migration / Twin / Grain boundary melting |
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| Research Abstract |
In order to clarify the effects of grain boundaries on the recrystallization of bicrystals, 99.99mass% aluminum bicrystals and 99.98mass% copper ones were prepared by using the Bridgman technique and were tensile-deformed to the strains of 30% and 50%. Then, their thin films were examined by the heating stage for high temperature in situ observation of TEM.
As the result of it, 1. The strain induced boundary migration occurs in the side of crystal in which deformation bands are formed due to the pile-up of edge dislocations to the boundaries. 2. While, the recrystallized grains whose orientations are obtained by the rotation of the deformed matrix about (111> axes are formed like islands near the boundaries to which screw dislocations are piled-up. 3. In the case of copper bicrystils, the occurrence of twins are frequently observed in both stages in the nucleation and the growth of new grains. The stacking fault energy of copper is relatively smalls so perfect dislocations easily separates to partial dislocations. At recrystallization temperature tangled dislocations do not loose and poligonize easily. 4. The boundaries in thin films of aluminum bicrystals have melt at the apparent temperature of about 0.9TM [K], where TM is the melting temperature of the corresponding bulk material. While, those of copper bicrystals have done at the very low apparent temperature of about 0.5TM.
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Research Products
(12 results)
