Microstructure and Properties of Surface Nanostructured Copper

2011 ◽  
Vol 328-330 ◽  
pp. 1606-1609
Author(s):  
Wan Ming Lin ◽  
Yin Hui Wei ◽  
Li Feng Hou
Keyword(s):  
Copper Plate ◽  
Surface Mechanical Attrition Treatment ◽  
Hardness Testing ◽  
Surface Layers ◽  
Materials Properties ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
The Matrix ◽  
Novel Method ◽  
Potentiodynamic Anodic Polarization

Surface nanocrystallization (SNC) is a novel method for improving materials properties. Nanostructured surface layers of about 20 μm thickness were produced in copper plate samples by means of surface mechanical attrition treatment (SMAT). The behaviors of the SMAT samples were investigated by using transmission electron microscopy (TEM), Vickers hardness testing and potentiodynamic anodic polarization tests. The experimental results showed that the longer the peening time was performed on the copper pate samples, the thicker the deformation layers formed. The microhardness results for the top surface layer of the copper plate sample are 1.723 GPa and 1.752 GPa for 45 and 60 min, respectively, which are about two times higher than that of the matrix. The primary passivate potential of nanocrystalline copper was more negative than that of coarse-grain copper.

“In-Situ Network” Composite Fibers of Pbzt/Nylon

1988 ◽  
Vol 134 ◽  
Author(s):  
C. Robin Hwang ◽  
Michael F. Malone ◽  
Richard J. Farris ◽  
David C. Martin ◽  
Edwin L. Thomas
Keyword(s):  
Nitrogen Adsorption ◽  
Composite Fibers ◽  
Electron Microscopies ◽  
X Ray Scattering ◽  
Transmission Electron ◽  
Before And After ◽  
The Matrix ◽  
Novel Method ◽  
20 Nm

ABSTRACTA novel method of preparing PBZT/nylon composite fibers by infiltrating nylon into pure PBZT fiber is described. The pure PBZT fiber formed a microfibrillar network structure during coagulation, which is effective in reinforcing the matrix in the “in-situ network” composite fibers (designated IC). These new composite fibers exhibit nearly indistinguishable mechanical properties as those of “molecular” composite fibers (MC) prepared from isotropic solutions before and after tension heat-treatment (E = 44 GPa, σ = 430 MPa, ε = 1.2 %, σc = 250 MPa, G = 1.75 GPa) for PBZT/nylon weight ratios equal to unity.The fine structure of pure PBZT and its composite fibers spun from isotropic solutions was characterized using techniques based on nitrogen adsorption, small-angle X-ray scattering, scanning and transmission electron microscopies. The structure of both type of composites was found to be a microfibrillar network of PBZT in a matrix of amorphous nylon. The average diameters of the PBZT microfibrils were in the range of 10 to 20 nm for the IC and 4 nm for the MC.

Ultrasonic Surface Mechanical Attrition of Commercially Pure Ti to Induce Nanocrystalline Surface Layer

2010 ◽  
Vol 442 ◽  
pp. 152-157 ◽  
Author(s):  
M. Mansoor ◽  
J. Lu
Keyword(s):  
Pure Titanium ◽  
Nanocrystalline Structure ◽  
Surface Mechanical Attrition Treatment ◽  
X Ray Diffraction ◽  
Annealed Condition ◽  
X Ray ◽  
Commercially Pure ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Xrd And Tem

In the domain of incremental nanotechnology, surface mechanical attrition treatment is a technique which can transform superficial structure of a material to nanocrystalline without changing the chemical composition. This study is a part of the development and implementation of the technique by using ultrasonic vibrations. The material used is pure titanium in rolled and annealed condition. The nanocrystalline structure is characterized using X-ray diffraction (XRD), and transmission electron microscopy (TEM). The measured grain size is in the order of 5~60 nm. A correlation in the results of XRD and TEM is also discussed.

Nanostructured 316 Stainless Steel Prepared under Traction by Surface Mechanical Attrition Treatment

2009 ◽  
Vol 614 ◽  
pp. 201-206
Author(s):  
Xiao Fang Yang ◽  
Jian Lu
Keyword(s):  
Stainless Steel ◽  
Optical Microscope ◽  
Steel Sample ◽  
Surface Mechanical Attrition Treatment ◽  
Stainless Steel Sample ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Nanostructured Layer ◽  
Nanoindentation Measurement ◽  
Measurement Results

A nanostructured 316 austenitic stainless steel sample was prepared under traction using a new surface mechanical attrition treatment (SMAT) system. The microstructure of the surface layer of the SMATed sample was characterized using an optical microscope and transmission electron microscope (TEM). Microhardness on the cross-section was investigated by nanoindentation measurement. Results showed that a deeper nanostructured layer was obtained in comparison with that of the sample SMATed without traction.

scholarly journals Fabrication and Nanostructured Surface Layers of Al Alloy by Surface Vibrational Mechanical Attrition

2001 ◽  
Vol 697 ◽  
Author(s):  
X. Wu ◽  
Y. Hong ◽  
J. Lu ◽  
K. Lu
Keyword(s):  
Processing Time ◽  
Al Alloy ◽  
Nanostructured Surface ◽  
Surface Layers ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Boundary Rotation ◽  
Nano Grains ◽  
Nanometer Regime ◽  
Simultaneous Evolution

AbstractNanograins were introduced into the surface layers of an Al-alloy during surface vibrational mechanical attrition. Transmission electron microscopy revealed that microstructures developed with an increase in strain, in the following sequence, i.e., lamellar microbands of elongated subgrains, equiaxed submicro-, and nano-grains respectively. The grain subdivision into the subgrains was found to be the main mechanism responsible for grain refinement. The simultaneous evolution of high boundary misorientations was ascribed to the boundary rotation for accommodating further strains. Results showed that the grains could refine remarkably into the nanometer regime (<100 nm) within the outer surface of the layer. The depth of the nanocrystal layers increased and the grain size decreased with the extension of processing time. The nanocrystal layers evidenced an increase in hardness.

scholarly journals MICROSTRUCTURE EVOLUTION AND DEFORMATION FEATURE OF AZ31 MAGNESIUM ALLOY DURING SEVERE PLASTIC DEFORMATION

2012 ◽  
Vol 06 ◽  
pp. 503-508
Author(s):  
LI-FENG HOU ◽  
YING-HUI WEI ◽  
XUE-FENG SHU
Keyword(s):  
Surface Layer ◽  
Magnesium Alloy ◽  
Microstructure Evolution ◽  
Az31 Magnesium Alloy ◽  
Surface Mechanical Attrition Treatment ◽  
Nanostructured Surface ◽  
Deformation Feature ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Refinement Process

A nanostructured surface layer was produced on commercially AZ31 magnesium alloy using surface mechanical attrition treatment (SMAT). The microstructure evolution and deformation feature along the depth of the treated surface layer were characterized by transmission electron microscope (TEM) investigations. The grain refinement process, accompanied by an increase in the surface layer, involves: the onset of twins; the formation of microbands associated with the dislocation slipping; the subdivision of microbands into low angle grains and then highly disoriented polygonal submicronic grains, and further breakdown into randomly oriented nanograins with progression of dynamic recrystallization.

Surface Nanocrystallization of Zircaloy-4 by Surface Mechanical Attrition Treatment

2010 ◽  
Vol 658 ◽  
pp. 452-455 ◽  
Author(s):  
Cong Hui Zhang ◽  
Xiao Ge Duan ◽  
Lian Zhou ◽  
Xin Zhe Lan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Grain Size ◽  
Surface Hardness ◽  
Surface Mechanical Attrition Treatment ◽  
Dislocation Slip ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Average Grain Size ◽  
Mechanical Twins

A nanostructured surface layer was induced on zircaloy-4 by the method of surface mechanical attrition treatment (SMAT). X-ray diffraction and microhardness tester were applied to identify the average grain size and hardness of specimen processed for different duration, transmission electron microscopy and high-resolution transmission electron microscopy were adopted to observe the microstructure of specimen. The results showed that the surface hardness enhanced gradually and then stabilized with the processing duration increasing, while the average grain size declined gradually, to the minimum 20 nm at 15 min, then increased. The formation of nanocrystalline was due to the mechanical twins and dislocation slip.

Thermal Stability of Nanocrystalline Ti6Al4V Produced by Surface Mechanical Attrition Treatment

2017 ◽  
Vol 898 ◽  
pp. 41-46
Author(s):  
Quan Tong Yao ◽  
Meng Nan Xing ◽  
Guang Lan Zhang ◽  
Wei Ping Tong
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Pure Titanium ◽  
Surface Mechanical Attrition Treatment ◽  
X Ray ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Nanocrystalline Layer ◽  
Thermal Stability Of ◽  
Scanning Electron

A pollution-free nanocrystalline layer was prepared on the surface of Ti6Al4V by surface mechanical attrition treatment (SMAT). The nanocrystalline samples were vacuum annealed at various temperatures and for different periods of time. The microstructure and thermal stability were characterized by X-ray (XRD), scanning electron microscopy (SEM) and, transmission electron microscopy (TEM). The results showed that the nanocrystalline Ti6Al4V presented a satisfactory thermal stability with the annealed temperature below 650°C. The critical growth temperature for nanocrystalline Ti6Al4V is 100°C higher than that for pure titanium.

Semi-Massive Nanocrystallised Composites: From the Process to Mechanical and Microstructural Investigations

2013 ◽  
Vol 762 ◽  
pp. 487-492 ◽  
Author(s):  
Laurent Waltz ◽  
Delphine Retraint ◽  
Arjen Roos
Keyword(s):  
Microstructural Characterization ◽  
Tensile Tests ◽  
Austenitic Steels ◽  
Surface Mechanical Attrition Treatment ◽  
Three Point Bending ◽  
Steel Sheets ◽  
Transmission Electron ◽  
Mechanical Attrition ◽  
Refinement Mechanism ◽  
Duplex Process

The aim of the present study is first to describe an original process, the so called duplex process, whose feature is the coupling between the well-known SMAT (Surface Mechanical Attrition Treatment) and the traditional co-rolling. The first step of this process consists of SMA-Treatment of 316L stainless steel sheets to generate nanocrystalline layers on their top surfaces according to the grain refinement mechanism of austenitic steels which is well described in the literature. During the second step, three treated sheets are co-rolled at 550°C to obtain a semi-massive nanocrystallised multilayer structure with improved mechanical strength alternating nanocrystalline, transition and coarse grain layers. The second part of this work deals with the mechanical and the microstructural characterization of the as-obtained structures. Thus, sharp nanoindentation tests performed over the cross section of the laminates coupled with Transmission Electron Microscopy (TEM) confirm the presence of nanograins after the thermomechanical treatment. In addition, the enhanced yield strength demonstrated by tensile tests correlate well with the theoretical volume fractions of nanoand transition layers. The interface cohesion between the sheets is tested by three-point bending tests and the interface bonding is evaluated by microstructural observations.

Processing of nanostructured metals and alloys via plastic deformation

MRS Bulletin ◽  
2010 ◽  
Vol 35 (12) ◽  
pp. 977-981 ◽  
Author(s):  
Yuntian Zhu ◽  
Ruslan Z. Valiev ◽  
Terence G. Langdon ◽  
Nobuhiro Tsuji ◽  
Ke Lu
Keyword(s):  
Plastic Deformation ◽  
High Pressure Torsion ◽  
Metals And Alloys ◽  
Surface Mechanical Attrition Treatment ◽  
Nanostructured Surface ◽  
Surface Layers ◽  
Nanostructured Metals ◽  
Angular Pressing ◽  
Mechanical Attrition ◽  
Processing Techniques

Plastic deformation can effectively produce nanostructured metals and alloys in bulk or surface-layer forms that are suitable for practical structural or functional applications. Such nanostructured materials are porosity-free and contamination-free, and therefore they are ideal for studying fundamental mechanisms and mechanical properties. In this article, we first give an overview of the principles of grain refinement by plastic deformation and an introduction to the reported processing techniques. Then the four most-developed and promising techniques will be described in detail: equal-channel angular pressing, high-pressure torsion, accumulative roll bonding for bulk nanostructured metals, and surface mechanical attrition treatment for nanostructured surface layers.

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