Crystallinity changes and mechanical properties of syndiotactic 1,2-polybutadiene under plastic deformation

Severe plastic deformation is an effective method for improving the mechanical properties of metallic alloys through promoting the grain structure. In the present work, simple cyclic extrusion compression technique (SCEC) has been developed for producing a fine structure of cast Al-1 wt. % Cu alloy and consequently enhancing the mechanical properties of the studied alloy. It was found that the grain structure was significantly reduced from 1500 µm to 100 µm after two passes of cyclic extrusion. The ultimate tensile strength and elongation to failure of the as-cast alloy were 110 MPa and 12 %, respectively. However, the corresponding mechanical properties of the two pass CEC deformed alloy are 275 MPa and 35%, respectively. These findings ensure that a significant improvement in the grain structure has been achieved. Also, cyclic extrusion deformation increased the surface hardness of the alloy by 49 % after two passes. FE-simulation model was adopted to simulate the deformation behavior of the material during the cyclic extrusion process using DEFORMTM-3D Ver11.0. The FE-results revealed that SCEC technique was able to impose severe plastic strains with the number of passes. The model was able to predict the damage, punch load, back pressure, and deformation behavior.

Download Full-text

Friction Force and Stresses Analysis for Contact of Assembled Details

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.113.334 ◽

2006 ◽

Vol 113 ◽

pp. 334-338

Author(s):

Z. Dreija ◽

O. Liniņš ◽

Fr. Sudnieks ◽

N. Mozga

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Plastic Deformation ◽

Friction Force ◽

Sliding Friction ◽

Friction Model ◽

Contact Interface ◽

Finite Element Program ◽

Elastic Plastic ◽

Element Program

The present work deals with the computation of surface stresses and deformation in the presence of friction. The evaluation of the elastic-plastic contact is analyzed revealing three distinct stages that range from fully elastic through elastic-plastic to fully plastic contact interface. Several factors of sliding friction model are discussed: surface roughness, mechanical properties and contact load and areas that have strong effect on the friction force. The critical interference that marks the transition from elastic to elastic- plastic and plastic deformation is found out and its connection with plasticity index. A finite element program for determination contact analysis of the assembled details and due to details of deformation that arose a normal and tangencial stress is used.

Download Full-text

Influence of Hydrostatic Extrusion on the Mechanical Properties of the Model Al-Mg Alloys

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-05628-0 ◽

2021 ◽

Author(s):

Aleksandra Towarek ◽

Wojciech Jurczak ◽

Joanna Zdunek ◽

Mariusz Kulczyk ◽

Jarosław Mizera

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Tensile Strength ◽

Microstructural Analysis ◽

Tensile Tests ◽

Hydrostatic Extrusion ◽

Microstructure Formation ◽

Initial State ◽

Degree Of Deformation ◽

Al Mg Alloys

AbstractTwo model aluminium-magnesium alloys, containing 3 and 7.5 wt.% of Mg, were subjected to plastic deformation by means of hydrostatic extrusion (HE). Two degrees of deformation were imposed by two subsequent reductions of the diameter. Microstructural analysis and tensile tests of the materials in the initial state and after deformation were performed. For both materials, HE extrusion resulted in the deformation of the microstructure—formation of the un-equilibrium grain boundaries and partition of the grains. What is more, HE resulted in a significant increase of tensile strength and decrease of the elongation, mostly after the first degree of deformation.

Download Full-text

Microstructural Characterization and Mechanical Properties of Ti-6Al-4V Alloy Subjected to Dynamic Plastic Deformation Achieved by Multipass Hammer Forging with Different Forging Temperatures

Advances in Materials Science and Engineering ◽

10.1155/2019/6410238 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Xiurong Fang ◽

Jiang Wu ◽

Xue Ou ◽

Fuqiang Yang

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Volume Fraction ◽

Microstructural Characterization ◽

Optical Microscope ◽

Strain Rates ◽

Materials Properties ◽

Forging Process ◽

Hammer Forging ◽

Dynamic Plastic Deformation

Dynamic plastic deformation (DPD) achieved by multipass hammer forging is one of the most important metal forming operations to create the excellent materials properties. By using the integrated approaches of optical microscope and scanning electron microscope, the forging temperature effects on the multipass hammer forging process and the forged properties of Ti-6Al-4V alloy were evaluated and the forging samples were controlled with a total height reduction of 50% by multipass strikes from 925°C to 1025°C. The results indicate that the forging temperature has a significant effect on morphology and the volume fraction of primary α phase, and the microstructural homogeneity is enhanced after multipass hammer forging. The alloy slip possibility and strain rates could be improved by multipass strikes, but the marginal efficiency decreases with the increased forging temperature. Besides, a forging process with an initial forging temperature a bit above β transformation and finishing the forging a little below the β transformation is suggested to balance the forging deformation resistance and forged mechanical properties.

Download Full-text

Tailoring a Low Young Modulus for a Beta Titanium Alloy by Combining Severe Plastic Deformation with Solution Treatment

Materials ◽

10.3390/ma14133467 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3467

Author(s):

Anna Nocivin ◽

Doina Raducanu ◽

Bogdan Vasile ◽

Corneliu Trisca-Rusu ◽

Elisabeta Mirela Cojocaru ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Plastic Deformation ◽

Severe Plastic Deformation ◽

Young’S Modulus ◽

Young's Modulus ◽

Solution Treatment ◽

Young Modulus ◽

Orthopedic Implants ◽

Beta Titanium Alloy

The present paper analyzed the microstructural characteristics and the mechanical properties of a Ti–Nb–Zr–Fe–O alloy of β-Ti type obtained by combining severe plastic deformation (SPD), for which the total reduction was of etot = 90%, with two variants of super-transus solution treatment (ST). The objective was to obtain a low Young’s modulus with sufficient high strength in purpose to use the alloy as a biomaterial for orthopedic implants. The microstructure analysis was conducted through X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) investigations. The analyzed mechanical properties reveal promising values for yield strength (YS) and ultimate tensile strength (UTS) of about 770 and 1100 MPa, respectively, with a low value of Young’s modulus of about 48–49 GPa. The conclusion is that satisfactory mechanical properties for this type of alloy can be obtained if considering a proper combination of SPD + ST parameters and a suitable content of β-stabilizing alloying elements, especially the Zr/Nb ratio.

Download Full-text

Influence of Melt Temperature on Compressive Plasticity of a Cu-Zr-Al Bulk Metallic Glass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.146-147.517 ◽

2010 ◽

Vol 146-147 ◽

pp. 517-521

Author(s):

Sheng Hui Xie ◽

Xie Rong Zeng ◽

Dong Ju Fu ◽

Lei Zhao ◽

Qiang Hu

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Metallic Glasses ◽

Mechanical Performance ◽

Casting Temperature ◽

Thermal And Mechanical Properties ◽

Micro Hardness ◽

Melt Temperature ◽

Hardness Tests ◽

Important Solution

Cu47.5Zr47.5Al5 bulk metallic glasses (BMGs) were cast from the melt temperature 1143 to 1373 K. The structure, thermal and mechanical properties of the BMGs were investigated by XRD, DSC, HRTEM, dilatometric measurements, micro-hardness tests and uniaxial compression. The results indicate that the microstructure and mechanical performance of BMGs are closely affected by the casting temperature. Proper casting temperature ensures the BMGs with large relaxed excess free volume (REFV) and nano-crystallites, which favor the plastic deformation in Cu47.5Zr47.5Al5 BMGs. Regulating the preparing parameters is an important solution to good plasticity in BMGs.

Download Full-text

Deformation and Heat Treatment of Cold Drawn Gold

Materials Science Forum ◽

10.4028/www.scientific.net/msf.550.289 ◽

2007 ◽

Vol 550 ◽

pp. 289-294

Author(s):

Suk Hoon Kang ◽

Jae Hyung Cho ◽

Joon Sub Hwang ◽

Jong Soo Cho ◽

Yong Jin Park ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Plastic Deformation ◽

Mechanical Stability ◽

Ion Beam ◽

Quantitative Measure ◽

Electron Backscattered Diffraction ◽

Conducting Path ◽

Deformation And Heat Treatment ◽

Gold Wires

Cold drawn gold wires are widely applied in electronic packaging process to interconnect micro-electronic components. They basically provides a conducting path for electronic signal transfer, and experience thermo-mechanical loads in use. The mechanical stability of drawn gold wires is a matter of practical concern in the reliable functioning of electronic devices. It is known that mechanical properties of materials are deeply related to the microstructure. With appropriate control of deformation and heat processes, the mechanical properties of final products, such as tensile strength and elongation can be improved. Severe plastic deformation by torsion usually contributes to grain refinement and increment of strength. In this study, microstructure variations with torsion strain followed by drawing and heat treatment were investigated. Analyses by focused ion beam (FIB) and electron backscattered diffraction (EBSD) were carried out to characterize the effect of deformation and heat treatment on the drawn gold wires. Pattern quality of EBSD measurements was used as a quantitative measure for plastic deformation.

Download Full-text

Effect of Interfacial Properties on the Mechanical Behavior of Bone-Like Materials: A Numerical Study

International Journal of Applied Mechanics ◽

10.1142/s1758825117500144 ◽

2017 ◽

Vol 09 (01) ◽

pp. 1750014 ◽

Cited By ~ 7

Author(s):

Xingguo Li ◽

Bingbing An ◽

Dongsheng Zhang

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Numerical Study ◽

Element Model ◽

Interfacial Behavior ◽

Yield Behavior ◽

Bonding Property ◽

The Matrix ◽

Bonding Properties ◽

Superior Mechanical Properties

Interfacial behavior in the microstructure and the plastic deformation in the protein matrix influence the overall mechanical properties of biological hard tissues. A cohesive finite element model has been developed to investigate the inelastic mechanical properties of bone-like biocomposites consisting of hard mineral crystals embedded in soft biopolymer matrix. In this study, the complex interaction between plastic dissipation in the matrix and bonding properties of the interface between minerals and matrix is revealed, and the effect of such interaction on the toughening of bone-like biocomposites is identified. For the case of strong and intermediate interfaces, the toughness of biocomposites is controlled by the post yield behavior of biopolymer; the matrix with low strain hardening can undergo significant plastic deformation, thereby promoting enhanced fracture toughness of biocomposites. For the case of weak interfaces, the toughness of biocomposites is governed by the bonding property of the interface, and the post-yield behavior of biopolymer shows negligible effect on the toughness. The findings of this study help to direct the path for designing bioinspired materials with superior mechanical properties.

Download Full-text

Effect of Full- and Small-Scale Reeling Simulation on Mechanical Properties of Weldable 13Cr Seamless Line Pipe

Volume 4A: Pipeline and Riser Technology ◽

10.1115/omae2013-10681 ◽

2013 ◽

Cited By ~ 2

Author(s):

Hidenori Shitamoto ◽

Nobuyuki Hisamune

Keyword(s):

Mechanical Properties ◽

Plastic Deformation ◽

Oil And Gas ◽

Small Scale ◽

Line Pipe ◽

Offshore Pipeline ◽

Oil And Gas Pipelines ◽

Before And After ◽

Offshore Oil And Gas ◽

Offshore Oil

There are several methods currently being used to install offshore oil and gas pipelines. The reel-lay process is fast and one of the most effective offshore pipeline installation methods for seamless, ERW, and UOE line pipes with outside diameters of 18 inches or less. In the case of the reel-laying method, line pipes are subjected to plastic deformation multiplication during reel-laying. It is thus important to understand the change of the mechanical properties of line pipes before and after reel-laying. Therefore, full-scale reeling (FSR) simulations and small-scale reeling (SSR) simulations are applied as evaluation tests for reel-laying. In this study, FSR simulations were performed to investigate the effect of cyclic deformation on the mechanical properties of weldable 13Cr seamless line pipes. Furthermore, SSR simulations were performed to compare the results obtained by FSR simulations.

Download Full-text

Percolation Effects in the Mechanical Properties of Granular Ni-A12O3 thin films

MRS Proceedings ◽

10.1557/proc-195-441 ◽

1990 ◽

Vol 195 ◽

Cited By ~ 3

Author(s):

T.E. Schlesinger ◽

A. Gavrin ◽

R.C. Cammarata ◽

C.-L. Chien

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Plastic Deformation ◽

Magnetic Properties ◽

Percolation Threshold ◽

Volume Fraction ◽

Electrical And Magnetic Properties ◽

Low Load

ABSTRACTThe mechanical properties of sputtered Ni-Al2O3 granular thin films were investigated by low load microharaness testing. It was found that the microhardness of these films displayed a percolation threshold at a nickel volume fraction of about 0.6, below which the hardness is greatly enhanced. This behavior is qualitatively similar to the electrical and magnetic properties of these types of films. A percolation threshold in hardness can be understood as due to a change in the mechanism for plastic deformation.

Download Full-text