30 research outputs found
ΠΠ½ΡΠ΅Π½ΡΠΈΠ²Π½Π°Ρ ΠΏΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠ°Ρ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΌΠ΅Π΄ΠΈ ΠΏΡΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ΅
The production of metallic submicrocrystalline and nanocrystalline materials with desired physicochemical properties is an important problem of modern materials science [1]. To date, several attempts have been made to grind grain size through deformation at a cryogenic temperature [2β4], and most of this work was carried out on highly plastic copper. An urgent task is a detailed study of the microstructure after cryogenic deformation, as well as its formation mechanisms. This work was aimed at certifying the microstructure of copper subjected to low-temperature deformation. For the certification of the microstructure, a relatively new method of automatic analysis of backscattered electron diffraction patterns (EBSD) was used [5]
ΠΠ½ΠΎΠΌΠ°Π»ΡΠ½ΡΠΉ ΡΠΎΡΡ Π·Π΅ΡΠ΅Π½ Π² ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎ-Π΄Π΅ΡΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΌΠ΅Π΄ΠΈ
Structural changes in cryogenically deformed copper during long-term (up to two years) room-temperature ageing were investigated. It is found that the structure formed under high (e=8.2) cryogenic deformation is unstable and is characterized by abnormalous grain growth. It is shown that the grain growth is preceded by a long (up to a year) incubation period. It is revealed that the structure rapidly losses stability with an increase in accumulated cryogenic strain
ΠΡΠΈΠΎΠ³Π΅Π½Π½Π°Ρ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΌΠ΅Π΄ΠΈ
The effect of cryogenic deformation on the structure refinement of copper was studied
Π€ΠΎΡΠΌΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ Π² Ρ ΠΎΠ΄Π΅ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΠΏΡΠΎΠΊΠ°ΡΠΊΠΈ ΠΌΠ΅Π΄ΠΈ
ΠΡΠΎΠ²Π΅Π΄Π΅Π½Π° ΡΡΠ°ΡΠ΅Π»ΡΠ½Π°Ρ Π°ΡΡΠ΅ΡΡΠ°ΡΠΈΡ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ ΠΈ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠ²ΠΎΠΉΡΡΠ² ΠΌΠ΅Π΄ΠΈ, ΠΏΠΎΠ΄Π²Π΅ΡΠ³Π½ΡΡΠΎΠΉ ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΉ ΡΡΠ΅ΠΏΠ΅Π½ΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΠΏΡΠΎΠΊΠ°ΡΠΊΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΠ²ΠΎΠ»ΡΡΠΈΡ Π·Π΅ΡΠ΅Π½Π½ΠΎΠΉ ΡΡΡΡΠΊΡΡΡΡ, Π² ΠΎΡΠ½ΠΎΠ²Π½ΠΎΠΌ, ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ»Π°ΡΡ Π³Π΅ΠΎΠΌΠ΅ΡΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΡΡΡΠ΅ΠΊΡΠΎΠΌ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ. ΠΠ° ΠΎΡΠ½ΠΎΠ²Π΅ Π°Π½Π°Π»ΠΈΠ·Π° ΡΠ΅ΠΊΡΡΡΡΠ½ΡΡ
Π΄Π°Π½Π½ΡΡ
Π±ΡΠ» ΡΠ΄Π΅Π»Π°Π½ Π²ΡΠ²ΠΎΠ΄, ΡΡΠΎ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΡΠ΅ ΡΡΠ»ΠΎΠ²ΠΈΡ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ Π½Π΅ ΠΏΡΠΈΠ²Π΅Π»ΠΈ ΠΊ ΡΡΠ½Π΄Π°ΠΌΠ΅Π½ΡΠ°Π»ΡΠ½ΠΎΠΌΡ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠ° ΠΏΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΠ΅ΡΠ΅Π½ΠΈΡ, ΠΈ ΠΎΡΠ½ΠΎΠ²Π½ΡΠΌ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠΎΠΌ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ Π±ΡΠ»ΠΎ Π΄ΠΈΡΠ»ΠΎΠΊΠ°ΡΠΈΠΎΠ½Π½ΠΎΠ΅ {111} ΡΠΊΠΎΠ»ΡΠΆΠ΅Π½ΠΈΠ΅. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½Π°Ρ ΠΏΡΠΎΠΊΠ°ΡΠΊΠ° ΠΏΡΠΈΠ²ΠΎΠ΄ΠΈΡ ΠΊ ΡΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠΌΡ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΈ Π½Π΅ΠΊΠΎΡΠΎΡΠΎΠΌΡ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΠΏΠ»Π°ΡΡΠΈΡΠ½ΠΎΡΡΠΈ
ΠΠ»ΠΈΡΠ½ΠΈΠ΅ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΠΎΡΠ°Π΄ΠΊΠΈ Π½Π° ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ ΠΊΠ°ΡΠ°Π½ΠΎΠΉ ΠΌΠ΅Π»ΠΊΠΎΠ·Π΅ΡΠ½ΠΈΡΡΠΎΠΉ ΠΌΠ΅Π΄ΠΈ
ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Π° Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΡΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠ³ΠΎ ΠΈΠ·ΠΌΠ΅Π»ΡΡΠ΅Π½ΠΈΡ Π·Π΅ΡΠ΅Π½ Π² ΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΈ ΡΠΈΡΡΠΎΠΉ ΠΌΠ΅Π΄ΠΈ ΠΏΡΡΠ΅ΠΌ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΠΎΡΠ°Π΄ΠΊΠΈ. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ ΡΠ²ΠΎΠ»ΡΡΠΈΡ ΡΡΡΡΠΊΡΡΡΡ Π² ΡΠ΅Π»ΠΎΠΌ ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΠ»Π°ΡΡ ΡΠΏΠ»ΡΡΠΈΠ²Π°Π½ΠΈΠ΅ΠΌ ΠΈΡΡ
ΠΎΠ΄Π½ΡΡ
Π·Π΅ΡΠ΅Π½ Π² Ρ
ΠΎΠ΄Π΅ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ. ΠΠ½Π°Π»ΠΈΠ· ΡΠ΅ΠΊΡΡΡΡΠ½ΡΡ
Π΄Π°Π½Π½ΡΡ
ΠΈ ΡΠΏΠ΅ΠΊΡΡΠ° ΡΠ°Π·ΠΎΡΠΈΠ΅Π½ΡΠΈΡΠΎΠ²ΠΎΠΊ ΠΏΠΎΠΊΠ°Π·Π°Π», ΡΡΠΎ ΠΎΡΠ½ΠΎΠ²Π½ΡΠΌ ΠΌΠ΅Ρ
Π°Π½ΠΈΠ·ΠΌΠΎΠΌ ΠΏΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΠ΅ΡΠ΅Π½ΠΈΡ ΡΠ²Π»ΡΠ»ΠΎΡΡ ΠΎΠ±ΡΡΠ½ΠΎΠ΅ {111} Π΄ΠΈΡΠ»ΠΎΠΊΠ°ΡΠΈΠΎΠ½Π½ΠΎΠ΅ ΡΠΊΠΎΠ»ΡΠΆΠ΅Π½ΠΈΠ΅ ΠΏΡΠΈ Π½Π΅ΡΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠΌ Π²ΠΊΠ»Π°Π΄Π΅ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π΄Π²ΠΎΠΉΠ½ΠΈΠΊΠΎΠ²Π°Π½ΠΈΡ
ΠΠ»ΠΈΡΠ½ΠΈΠ΅ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΠΏΡΠΎΠΊΠ°ΡΠΊΠΈ Π½Π° ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ ΠΈ ΠΌΠ΅Ρ Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΠΌΠ΅Π΄ΠΈ
The effect of cryogenic rolling on the structure and mechanical properties of copper was studied. The grain structure evolution was shown to be mainly governed by the geometrical effect of the imposed strain whereas the contribution of the mechanical twinning and grain subdivision was found to be not significant. The analysis of the developed texture demonstrated that the plastic flow arises mainly from conventional {111} slip. The cryogenic rolling was shown to increase strength and decrease ductility and both effects might be attributed to the substructure
ΠΠ»Π°ΡΡΠΈΡΠ΅ΡΠΊΠ°Ρ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΡ ΠΌΠ΅Π΄ΠΈ ΠΏΡΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ΅
The production of submicrocrystalline and nanocrystalline materials with desired properties is an important task of modern materials science [1]. One of the promising directions in this area is deformation at a cryogenic temperature [2-5]. However, the effectiveness of this approach is not yet completely clear, and therefore the urgent task is to study the microstructure after cryogenic deformation, as well as the mechanisms of its formation
ΠΡΠ΅Π½ΠΊΠ° ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ Π΄Π»Ρ ΠΈΠ·ΠΌΠ΅Π»ΡΡΠ΅Π½ΠΈΡ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ ΠΊΡΡΠΏΠ½ΠΎΠ·Π΅ΡΠ½ΠΈΡΡΠΎΠΉ ΠΌΠ΅Π΄ΠΈ
Influence of cryogenic conditions of deformation on refining the structural Cu components in case of initial large grain structure. It has been found that deformation at cryogenic temperature intensifies process of forming the strain origin boundaries and activates mechanical twinning, however, does not make it possible to obtain nanocrystalline structures
ΠΠ± ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ ΠΊΡΠΈΠΎΠ³Π΅Π½Π½ΠΎΠΉ Π΄Π΅ΡΠΎΡΠΌΠ°ΡΠΈΠΈ Π΄Π»Ρ ΠΈΠ·ΠΌΠ΅Π»ΡΡΠ΅Π½ΠΈΡ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ ΠΌΠ΅Π΄ΠΈ
In the work, we studied and compared the microstructures of commercially pure copper subjected to the same strain at room temperature and at liquid-nitrogen temperature. It is found that at rather low plastic strain (slump, e=1.0), cryogenic temperature assists the activation of mechanical twinning and somewhat accelerates the formation of deformation boundaries. At high plastic strain (high-pressure shear, e=8.4), cryogenic temperature adds too little to microstructure refinement