The effects of surface-layer grain size and texture on deformation-induced surface roughening in polycrystalline titanium hardened by ultrasonic impact treatment

2020 ◽  
Vol 793 ◽  
pp. 139896 ◽  
Author(s):  
Е. Emelianova ◽  
V. Romanova ◽  
O. Zinovieva ◽  
R. Balokhonov
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Surface Roughening ◽  
Ultrasonic Impact Treatment

Ultrasonic Impact Treatment of Fine- and Coarse Grained Commercial Purity Titanium

2016 ◽  
Vol 1139 ◽  
pp. 12-15
Author(s):  
Rustam Hairullin ◽  
Anna Kozelskaya ◽  
Marina Kazachenok
Keyword(s):  
Plastic Deformation ◽  
Grain Size ◽  
Surface Layer ◽  
Electron Backscatter Diffraction ◽  
Coarse Grained ◽  
Commercial Purity ◽  
Ultrasonic Impact Treatment ◽  
Commercial Purity Titanium ◽  
Wide Range ◽  
Purity Titanium

The grain size effect on surface morphology, microstructure and mechanical properties of commercial purity titanium specimens subjected to ultrasonic impact treatment was studied. It was found by atomic force microscope that ultrasonic impact treatment of titanium specimens resulted in surface corrugation happens due to their severe plastic deformation. The profile height of the corrugated surface depends on the grain size of specimens and varies in a wide range. The thicknesses of a modified surface layer of fine-and coarse grained titanium specimens were studied. Electron backscatter diffraction (EBSD) analysis revealed that the plastic deformation was accompanied by twin and low angle boundary formation in the surface layer of titanium specimens. The effect of ultrasonic impact treatment on the microhardness of the surface layer of the specimens under study was investigated.

Roughening of Free Surface During Sheet Metal Forming

2013 ◽  
Vol 135 (2) ◽  
Author(s):  
Daw-Kwei Leu ◽  
Shue-Huye Sheen
Keyword(s):  
Surface Roughness ◽  
Grain Size ◽  
Surface Layer ◽  
Sheet Metal ◽  
Process Parameters ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Effective Strain ◽  
Surface Roughening ◽  
Proposed Model

This investigation concerns the effect of the process parameters on surface roughening during plastic deformation. The modeling is based on the assumption that surface roughness is proportional to the maximum shear stress on the surface layer. Therefore, an equation is developed in order to describe the relationship between the surface roughness and such process parameters as the initial roughness, grain size, effective strain, and maximum shear strain ratio on the surface layer. In a tensile test, the surface roughness increases nonlinearly with a normal anisotropic value and linearly with the effective strain or grain size. The surface roughness also increases nonlinearly with the effective stress and the strain hardening exponent under some fixed conditions. The normal anisotropic value must be considered in order to evaluate surface roughening during deformation. The experimental results support the proposed model. The proposed model improves our understanding of the mechanism of surface roughening in sheet metal forming.

scholarly journals Transformations of the Microstructure and Phase Compositions of Titanium Alloys during Ultrasonic Impact Treatment. Part I. Commercially Pure Titanium

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 562
Author(s):  
Alexey Panin ◽  
Andrey Dmitriev ◽  
Anton Nikonov ◽  
Marina Kazachenok ◽  
Olga Perevalova ◽  
...  
Keyword(s):  
Surface Layer ◽  
Phase Transformations ◽  
Pure Titanium ◽  
Surface Plastic ◽  
Commercially Pure Titanium ◽  
Ultrasonic Impact Treatment ◽  
Coordination Numbers ◽  
Microscopy Technique ◽  
Transmission Electron ◽  
Treated Sample

Experimental and theoretical studies helped to reveal patterns of surface roughening and the microstructure refinement in the surface layer of commercial pure titanium during ultrasonic impact treatment. Applying transmission electron microscopy technique, a gradient microstructure in the surface layer of the ultrasonically treated sample, where the grain size is varied from nano- to micrometers was revealed. It was shown that the surface plastic strains of the titanium sample proceeded according to the plastic ploughing mechanism, which was accompanied by dislocation sliding, twinning, and the transformations of the microstructure and phase composition. The molecular dynamics method was applied to demonstrate the mechanism of the phase transformations associated with the formation of stacking faults, as well as the reversible displacement of atoms from their sites in the hcp lattice, causing a change in coordination numbers. The role of the electronic subsystem in the development of the strain-induced phase transformations during ultrasonic impact treatment was discussed.

Surface Nanocrystallines of Fe3Al Produced by Surface Mechanical Attrition

2011 ◽  
Vol 320 ◽  
pp. 325-328 ◽  
Author(s):  
Jiang Wei Ren ◽  
Dong Li ◽  
Pei Quan Xu
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Surface Mechanical Attrition Treatment ◽  
Electronic Microscopy ◽  
X Ray ◽  
Structure And Morphology ◽  
Mechanical Attrition ◽  
Deformed Layer ◽  
Fe3al Intermetallic ◽  
Morphology Of Surface

A nanocrystallines surface layer was produced in Fe3Al intermetallic compound by surface mechanical attrition treatment (SMAT). The microstructure of deformed layer, phase structure and morphology of surface nanocrystallines were characterized through optical microscopy, X-ray diffractometry, transmission electronic microscopy and high resolution electronic microscopy. The results show that a deformed layer about 11μm wide is produced after 10min surface mechanical attrition. The grains on the top surface of Fe3Al are refined to nanocrystallines and the grain size of nanocrystallines is about 35nm. High density dislocations collect on the boundaries of grains. The formation of nanocrystallines is controlled by grain subdivision mechanism.

Effect of Surface Nano-Crystallization on Microstructure and Mechanic Properties of Commercial Pure Titanium

2004 ◽  
Vol 261-263 ◽  
pp. 1605-1610 ◽  
Author(s):  
Ai Ling Wen ◽  
R.M. Ren ◽  
Sheng Wu Wang ◽  
Shinichi Nishida
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Shot Peening ◽  
Pure Titanium ◽  
High Energy ◽  
X Ray Diffraction ◽  
Surface Microhardness ◽  
Commercial Pure Titanium ◽  
Nano Crystalline ◽  
Crystalline Surface

The paper investigated nano-crystallization on surface layer of commercial pure titanium by using high-energy shot peening. The grain size and the microstructure in deformed surface layer by high-energy shot peening are analyzed with X-ray diffraction and TEM etc. In addition, the variations of surface microhardness are examined after high-energy shot peening. The results described that the nano-crystalline surface layer have been formed in commercial pure titanium with a structure of hexagonal closet packet, by high-energy shot peening. The surface microhardness increases and the grain size in nano-crystalline surface layer diminishes, with increasing the time in high-energy shot peening. The minimum nano-crystalline grain size is approximately 40 nm.

scholarly journals Investigation of the effect of ultrasonic surface treatment before ion implantation on the structure of the surface layer of aluminum alloy 1201

2020 ◽  
Vol 315 ◽  
pp. 05002
Author(s):  
Viktor Ovchinnikov ◽  
Irina Kurbatova ◽  
Nadezda Uchevatkina
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Aluminum Alloy ◽  
Ion Implantation ◽  
Cathode Material ◽  
Surface Treatment ◽  
Ultrasonic Treatment ◽  
Nanocrystalline Structure ◽  
Depth Of Penetration ◽  
Ultrasonic Surface Treatment

The aim of this study was to study the properties of 1201 aluminum alloy after ultrasonic treatment and their evolution during subsequent ion implantation using the monotectic Cu-Pb alloy as the cathode material of the implant. It is shown that during ultrasonic treatment the surface layer of aluminum alloy 1201 undergoes significant changes. A nanocrystalline structure with a grain size of less than 200 microns is formed in it. Ultrasonic treatment of the surface of the target from alloy 1201 before implantation leads to a decrease in the depth of penetration of ions to 160–180 nm and the appearance of amorphization in the implanted layer.

scholarly journals The kinetic parameters of aerosols formed during combustion of modified wood

2018 ◽  
Vol 251 ◽  
pp. 02023
Author(s):  
Feodor Portnov
Keyword(s):  
Grain Size ◽  
Surface Layer ◽  
Chemical Properties ◽  
Quantitative Composition ◽  
Kinetic Properties ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
The Impact ◽  
And Chemical Properties ◽  
Modified Wood

The paper studies kinetic properties of aerosols formed in thermal degradation of wood. The impact of modifying agents in wood surface layer on the quantitative composition of smoke aerosol solids was analyzed. For this purpose, grain-size of aerosol solids was analyzed, and the physical and chemical properties of source and modified wood were assessed.

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