Effect of Carbon Nanofiber on Thermal and Tensile Properties of Polypropylene

Author(s):  
Yuanxin Zhou ◽  
Mohammad Monirul Hasan ◽  
Shaik Jeelani

In the present study, effect of vapor grown carbon nanofiber on the mechanical and thermal properties of polypropylene was investigated. Firstly, nanofibers were dry-mixed with polypropylene powder and extruded into filaments by using a single screw extruder. Then the tensile tests were performed on the single filament at the strain rate range from 0.02/min to 2/min. Experiments results show that both neat and nano-phased polypropylene were strain rate strengthening material. The tensile modulus and yield strength both increased with increasing strain rate. Experimental results also show that infusing nanofiber into polypropylene can increase tensile modulus and yield strength, but decrease the failure strain. At the same time, thermal properties of neat and nano-phased polypropylene were characterized by TGA. TGA results have showed that the nanophased system is more thermally stable. At last, a nonlinear constitutive equation has been developed to describe strain rate sensitive behavior of neat and nano-phased polypropylene.

2005 ◽  
Vol 297-300 ◽  
pp. 905-911 ◽  
Author(s):  
Xu Chen ◽  
Li Zhang ◽  
Masao Sakane ◽  
Haruo Nose

A series of tensile tests at constant strain rate were conducted on tin-lead based solders with different Sn content under wide ranges of temperatures and strain rates. It was shown that the stress-strain relationships had strong temperature- and strain rate- dependence. The parameters of Anand model for four solders were determined. The four solders were 60Sn-40Pb, 40Sn-60Pb, 10Sn-90Pb and 5Sn-95Pb. Anand constitutive model was employed to simulate the stress-strain behaviors of the solders for the temperature range from 313K to 398K and the strain rate range from 0.001%sP -1 P to 2%sP -1 P. The results showed that Anand model can adequately predict the rate- and temperature- related constitutive behaviors at all test temperatures and strain rates.


2020 ◽  
Vol 41 (4) ◽  
pp. 1224-1233
Author(s):  
Zenen Zepeda‐Rodríguez ◽  
Martin R. Arellano‐Martínez ◽  
Emilio Cruz‐Barba ◽  
Adalberto Zamudio‐Ojeda ◽  
Denis Rodrigue ◽  
...  

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Morteza Ghorbanzadeh Ahangari ◽  
Abdolhosein Fereidoon ◽  
Seyfolah Saedodin

AbstractIn the present work, the effect of different acid treatment times of singlewalled carbon nanotubes (SWNTs) on the mechanical and thermal properties of polypropylene (PP)/maleated polypropylene (PP-g-MA) nanocomposites was investigated. The acid treatment process was based on a mixture of concentrated sulphuric and nitric acids. The SWNTs were treated with the acid mixture for 1, 3, and 6 h. FTIR, Raman spectroscopy and TEM revealed the values of carboxylic groups, graphitization and morphology of acid treated SWNTs, respectively. The thermal and mechanical properties and the morphology of nanocomposites were investigated by tensile tests, DMTA, DSC, and SEM.


2013 ◽  
Vol 209 ◽  
pp. 6-9 ◽  
Author(s):  
Rajendra Doiphode ◽  
S.V.S. Narayana Murty ◽  
Nityanand Prabhu ◽  
Bhagwati Prasad Kashyap

Mg-3Al-1Zn (AZ31) alloy was caliber rolled at 250, 300, 350, 400 and 450 °C. The effects of caliber rolling temperature on the microstructure and tensile properties were investigated. The room temperature tensile tests were carried out to failure at a strain rate of 1 x 10-4s-1. The nature of stress-strain curves obtained was found to vary with the temperature employed in caliber rolling. The yield strength and tensile strength followed a sinusoidal behaviour with increasing caliber rolling temperature but no such trend was noted in ductility. These variations in tensile properties were explained by the varying grain sizes obtained as a function of caliber rolling temperature.


2020 ◽  
pp. 002199832096979
Author(s):  
Fatih Yıldırım ◽  
Necati Ataberk ◽  
Mürsel Ekrem

In this study, the thermal and mechanical properties of nanocomposite materials were investigated. Produced nanocomposite materials are epoxy-based and reinforced with Multiwalled Carbon Nano Tube dopped polyvinyl alcohol (PVA) nanofibers. Nanofibers were produced by the electrospinning method. Nanofibers were used for reinforcement as 5, 10, and 15 number of layers. These nanocomposite materials were subjected to uniaxial tensile tests at constant tensile speed in accordance with ASTM D882-02 standards. Tensile strength, elasticity modulus, Poisson's ratio, and toughness values were obtained and these values were compared with the values of reference pure epoxy samples without the nanofiber. For obtaining the thermal properties of the samples Thermogravimetric and Differential Thermal Analysis were performed. In order to investigate the damage mechanisms, the fractured tensile test specimens' surfaces were visualized by Scanning Electron Microscopy. Mechanical and thermal properties of the epoxy were improved by using the PVA nanofibers dopped the MWCNT.


Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2861
Author(s):  
Wenqing Li ◽  
Tieqiang Geng ◽  
Shaofan Ge ◽  
Zhengwang Zhu ◽  
Long Zhang ◽  
...  

The strain rate effect on the mechanical behavior of amorphous alloys has aroused general interest. Most studies in this area have focused on quasi-static and high strain-rate compressive deformations. However, experimental results have been few, or even non-existent, under a moderate strain-rate loading. This article extends the traditional split Hopkinson pressure bar (SHPB) technique to characterize compressive deformation of an amorphous alloy at medium strain rates. The compressive behavior of Zr65.25Cu21.75Al8Ni4Nb1 amorphous alloy shows a negative strain rate effect on the yield strength with a quasi-static, moderate to high strain-rate range, and the fracture angle increases from 44° at 10−5 s−1 to 60° at 4000 s−1 as strain rate increases. Herein, we introduce a modified cooperative shear model to describe the compressive behavior of the current amorphous alloy under a broad strain rate range. The model predicts that the normalized yield strength will linearly descend with logarithmic strain rate when the strain rate is less than a critical strain rate, however, which rapidly decreases linearly with the square of the strain rate at high strain rates. The predicted data of the model are highly consistent with the current experimental results. These findings provide support for future engineering applications of amorphous alloys.


e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarfraz H. Abbasi ◽  
Abdulhadi A. Al-Juhani ◽  
Anwar Ul-Hamid ◽  
Ibnelwaleed A. Hussein

AbstractIn this work, nanocomposites of low density polyethylene (LDPE) / multiwall carbon nanotubes (MWCNTs) were prepared using melt blending. The effects of CNT aspect ratio, CNT loading, CNT chemical modification and the presence of a compatibilizer (maleated polyethylene) on morphology, mechanical and thermal properties of the CNT/LDPE composites were studied. Different MWCNTs were used: long CNT (LCNT); COOH modified CNT (MCNT) and short CNT (SCNT). FE-SEM images of produced nanocomposites show agglomeration of the MWCNTs. Addition of compatibilizer to both LCNT and MCNT nanocomposites improved their dispersion in the LDPE matrix. Yield strength and modulus increased with loading of various MWCNTs. However, ultimate strength, percent elongation and toughness reduced significantly for CNT loadings of 2% CNT and higher. The addition of maleated PE resulted in improvements of Young’s modulus, yield strength and ultimate strength but no impact on elongation at break or toughness. Addition of compatibilizer did not affect the crystallinity of the produced nanocomposites. In general, the use of CNT with high aspect ratio and the addition of compatibilizer and chemical modification improved the dispersion of MWCNTs and consequently improved most of the mechanical properties except elongation at break and toughness.


2012 ◽  
Vol 430-432 ◽  
pp. 256-259 ◽  
Author(s):  
Yang Yang ◽  
Chun Fu Li ◽  
Kai Hong Song

TWIP steel containing 0.21% C, 24.4% Mn, 0.9% Si, 1.84% Al, 4.61% Cr, 1.89% Ni, 0.41% Mo and 0.012% Nb was investigated. Tensile tests of this steel were performed in the strain rate range of 10−4–10−3 s−1. Results indicate that tensile properties of TWIP steel at room temperature are sensitive to strain rate in the studied range. Analyses on the relationship between strain–hardening exponent and strain rates show that the formation of twins during deformation greatly affects the strain–hardening behavior of TWIP steels.


2014 ◽  
Vol 788 ◽  
pp. 334-339 ◽  
Author(s):  
Dan Yuan ◽  
Lei Wang ◽  
Yang Liu ◽  
Xiu Song ◽  
Jia Hua Liu

The dynamic strain aging (DSA) behavior of SA508-III steel was evaluated through tensile tests with different strain rates from 10-4 to 10-1s-1 at 350°C. The OM, SEM and TEM were carried out to observe the microstructures and fracture morphologies of the steel. The results show that the serrated flows appear in the stress-strain curves when the strain rate is between 10-3~10-2s-1, indicating that DSA occurs. Under the strain rate range, the tensile strength increases and the elongation and the reduction of area decrease. However, the fracture surface of the steel after tensile tests is still ductile. DSA in SA508-III steel at the strain rates from10-3 to 10-2s-1 is mainly caused by the interaction between the internal solute atoms and dislocations, which leads to the dislocations multiplication and the formation of sub-grain boundaries and dislocation cell structure.


2005 ◽  
Author(s):  
Yuanxin Zhou ◽  
Pingwen Mao ◽  
Mohammad F. Uddin ◽  
Shaikh Jeelani

In this paper, loading and loading-unloading tests of carbon fiber reinforced aluminum laminates (CRALL) have been carried out in a tensile impact apparatus, and quasi-static tensile tests have been performed on a MTS-810 machine. Complete stress-strain curves of composite in the strain rate range from 0.001–1200 1/s have been obtained. Experimental results show that CRALL composite is a strain rate sensitivity material, the tensile strength and failure strain both increased with increasing strain rate. A linear strain hardening model has been combined with Weibull distribution function to establish a constitutive equation for CRALL. The simulated stress-strain curves from model are in good agreement with the test data. The analysis of the model shows that the Weibull scale parameter, σ0, increased with increasing strain rate, but Weibull shape parameter, β, can be regarded as a constant.


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