Tatyana Konkova

Room-temperature instability of the structure of copper deformed at a cryogenic temperature

The structural changes in cryodeformed copper are studied during long-term (1–2 year) storage at room temperature. The material is found to be unstable: grain growth is detected. The revealed structural instability casts doubt on the use of cryogenic deformation to form a nanocrystalline structure in copper.

Formation of the microstructure in the course of low-temperature annealing of cryogenically deformed copper

The formation of the microstructure in the course of annealing of cryogenically deformed copper is investigated. It is shown that this material is very unstable, and the primary recrystallization in it is finished already after 1-h annealing at 150°C. The formation of the microstructure and texture in the course of the recrystallization are determined by the selective growth of grains with orientations close to (90;27;45), (80;31;35), and (55;30/60;0).

Microstructural characteristics of electrodeposited damascene copper lines

The high-resolution electron backscatter diffraction technique and transmission electron microscopy were applied to study microstructure in the overburden layer, in upper and bottom parts of as-deposited as well as subsequently annealed nanoscale (100 nm width) copper wires. It was shown that the temperature interval 100oC-200oC should be seen as a transition period of microstructure evolution in damascene copper lines.

Detection of recrystallized structure by means of automatic analysis of electron backscattered diffraction patterns

The possibility of applying the automatic analysis of electron backscattered diffraction (EBSD) patterns to reveal the recrystallized structure in the partially recrystallized material has been discussed. The analysis has been performed based on new experimental results. It has been shown that the EBSD method can be successfully used to investigate the recrystallization process.

EBSD Characterization of Cryogenically Rolled Type 321 Austenitic Stainless Steel

Electron backscatter diffraction was applied to investigate microstructure evolution during cryogenic rolling of type 321 metastable austenitic stainless steel. As expected, rolling promoted deformation-induced martensitic transformation which developed preferentially in deformation bands. Because a large fraction of the imposed strain was accommodated by deformation banding, grain refinement in the parent austenite phase was minimal. The martensitic transformation was found to follow a general orientation relationship, {111}γ||{0001}ε||{110}α′ and 〈110〉γ||〈11-20〉ε||〈111〉α′, and was characterized by noticeable variant selection.

EBSD анализ микроструктуры аустенитной стали после прокатки в криогенных условиях

This work is based on the use of electron backscatter diffraction (EBSD) methods to investigate the microstructure of metastable austeniticsteel 12X18H10T (321) after cryogenic rolling. Cryogenic deformation was accompanied by martensitic transformations, and the martensitic phase nucleation mainly in deformation bands. It is assumed that the proceeding of the martensitic transformation in the most deformed parts of the microstructure should prevent the evolution of deformation-induced boundaries in the austenite and, thus, inhibit the process of fragmentation of this phase. Mechanical twinning was the primary (or even sole) mechanism providing HAB formation in the austenite.

Annealing effect on the structure characteristics of nano-scale damascene copper lines

High-resolution electron backscatter diffraction (EBSD) technique was applied for systematic and detailed study of grain structure and texture changes in various microstructural regions of nano-scale damascene copper lines after annealing in a wide temperature range of 200-500°C. To ensure reliability of the obtained results, large EBSD maps including several thousand grains were obtained in each case. Above 200°C, the grain structure was established to be surprisingly stable in both the overburden layer as well as within the lines. The grain growth in the lines was supposed to be suppressed by pinning effect of second-phase particles entrapped during electrodeposition process.

Effect of annealing temperature on structure of electrodeposited nano-scale copper wires

High-resolution electron backscatter diffraction (EBSD) technique was employed to investigate structure evolution of electrodeposited and subsequently annealed nano-scale copper wires. The grain structure was found to be stable in the bottom area of a trench during the annealing process. The material was shown to exhibit a large fraction of low-angle boundaries as well as annealing twins.

Crystallographic analysis of abnormal grain growth in cryogenically deformed copper

Crystallographic orientation of abnormal coarse grains formed in copper after severe cryogenic deformation and further long-term storage at room temperature was analyzed. The orientation was found to be close to cube texture {100} . This phenomenon was shown can be associated with annealing twinning.Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright

Кристаллографический анализ аномального роста зерен в криогенно-деформированной меди

Crystallographic orientation of abnormal coarse grains formed in copper after severe cryogenic deformation and further long-term storage at room temperature was analyzed. The orientation was found to be close to cube texture {100} . This phenomenon was shown can be associated with annealing twinning.Strathprints is designed to allow users to access the research output of the University of Strathclyde. Unless otherwise explicitly stated on the manuscript, Copyright