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Articles 1 - 12 of 12

Full-Text Articles in Engineering

Effect Of Mg/B Ratio On The Superconductivity Of Mgb2 Bulk With Sic Addition, Yun Zhang, S X. Dou, Cheng Lu, Sihai Zhou, Wenxian Li Jan 2010

Effect Of Mg/B Ratio On The Superconductivity Of Mgb2 Bulk With Sic Addition, Yun Zhang, S X. Dou, Cheng Lu, Sihai Zhou, Wenxian Li

Faculty of Engineering - Papers (Archive)

To improve the self-field critical current density (Jc) and critical temperature (Tc) in SiC-doped MgB2, optimization of the nominal Mg/B mixing ratio has been performed. The effects of the nominal Mg/B mixing ratio (x:2) on the superconductivity, Raman spectra, current transport properties, and flux pinning mechanisms in MgB2 with 10 wt.% SiC doping were investigated systematically, with x varied from 1 to 1.2. It has been found that the sample with the Mg/B ratio of 1.15:2 exhibited the best Jc performance for all fields (0–8.5 T), and its Tc was also …


Temperature Effect On Microstructure And Electromagnetic Performance Of Polycarbosilane And Sugar-Doped Mgb2 Wires, Andrey V. Shcherbakov, Josip Horvat, Olga V. Shcherbakova, Nikolina Novosel, Emil Babic, S. X. Dou Jan 2010

Temperature Effect On Microstructure And Electromagnetic Performance Of Polycarbosilane And Sugar-Doped Mgb2 Wires, Andrey V. Shcherbakov, Josip Horvat, Olga V. Shcherbakova, Nikolina Novosel, Emil Babic, S. X. Dou

Faculty of Engineering - Papers (Archive)

The effect of processing temperature on structural and superconducting properties of 10 wt.% sugar- and 10 wt.% PCS-doped MgB2 wires is systematically investigated. It is demonstrated that these dopants significantly enhance the electromagnetic performance of Fe-clad MgB2 superconductor and increase its potential for practical application. The enhancement of in-field critical current density (Jc(Ba)) and upper critical field (Bc2) is due to formation of a large amount of lattice defects caused by impurities and C substitution into the MgB2 crystal lattice. High temperature sintering of sugar-doped sample results …


Effect Of Bulk Temperature On The Tribological Performance Of Aqueous Symmetric Tri-Block Copolymers (Ppo-Peo-Ppo And Peo-Ppo-Peo) Based Lubricant, Oyong Novareza, P B. Kosasih, A K. Tieu, Hongtao Zhu Jan 2010

Effect Of Bulk Temperature On The Tribological Performance Of Aqueous Symmetric Tri-Block Copolymers (Ppo-Peo-Ppo And Peo-Ppo-Peo) Based Lubricant, Oyong Novareza, P B. Kosasih, A K. Tieu, Hongtao Zhu

Faculty of Engineering - Papers (Archive)

This work investigates the effect of bulk temperature and the tribological performance of a number of symmetric triblock copolymers on MSI020 commonly in metal forming. It is to determine the best bulk temperature for the lubricants in order to apply in metal fOlming application. The triblock polymers are temperature dependant'. The polymers can be compeletly dissolved in solution since of hydrogen bonding in certain temperature. As temperature increases, the bond is weakend and the polymer break from the water and form dispersion in the water


Self-Doping Effect And Successive Magnetic Transitions In Superconducting Sr2 Vfeaso3, Guanghan Cao, Zhifeng Ma, Cao Wang, Yunlei Sun, Jinke Bao, Shuai Jiang, Yi Luo, Chunmu Feng, Yi Zhou, Zhi Xie, Fengchun Hu, Shiqiang Wei, I Nowik, I Felner, Lei Zhang, Zhu-An Xu, Fu-Chun Zhang Jan 2010

Self-Doping Effect And Successive Magnetic Transitions In Superconducting Sr2 Vfeaso3, Guanghan Cao, Zhifeng Ma, Cao Wang, Yunlei Sun, Jinke Bao, Shuai Jiang, Yi Luo, Chunmu Feng, Yi Zhou, Zhi Xie, Fengchun Hu, Shiqiang Wei, I Nowik, I Felner, Lei Zhang, Zhu-An Xu, Fu-Chun Zhang

Faculty of Engineering - Papers (Archive)

We have studied a quinary Fe-based superconductor Sr2VFeAsO3 by the measurements of x-ray diffraction, x-ray absorption, Mössbauer spectrum, resistivity, magnetization, and specific heat. This apparently undoped oxyarsenide is shown to be self-doped via electron transfer from the V3+ ions. We observed successive magnetic transitions within the VO2 layers: an antiferromagnetic transition at 150 K followed by a weak ferromagnetic transition at 55 K. The spin orderings within the VO2 planes are discussed based on mixed valence of V3+ and V4+.


Bauschinger Effect In Microalloyed Steels: Part I. Dependence On Dislocation-Particle Interaction, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis Jan 2010

Bauschinger Effect In Microalloyed Steels: Part I. Dependence On Dislocation-Particle Interaction, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis

Faculty of Engineering and Information Sciences - Papers: Part A

The Bauschinger effect (yield stress decreasing at the start of reverse deformation after forward prestrain) is an important factor in strength development for cold metal forming technology. In steels, the magnitude of the Bauschinger effect depends on composition, through the presence of microalloy precipitates, and prior processing, through the size and distribution of microalloy precipitates and presence of retained work hardening. In this article, the microstructures of two (Nb- and Nb-V-microalloyed) steel plates, in terms of (Ti,Nb,V,Cu)-rich particle distributions and dislocation densities, have been quantitatively related to the Bauschinger parameters for the same processing conditions. For the 12- to 50-nm …


A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford Jan 2010

A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford

Faculty of Engineering and Information Sciences - Papers: Part A

The marker variable technique offers a practical and easy method to address the validity threat on account of common method variance to the findings of individual studies. Hawever, the validity of the marker variable technique has not been established. This paper examines the validity threat to the marker variable technique arising from multiple criteria for the selection of the marker variable proposed in the literature. Our findings shaw that the conclusions that can be drawn under different criteria are significantly and substantially different, raising doubts about the validity of the marker variable technique. Proposals for developing theoretically grounded criteria for …


Effect Of Microstructural Morphology On The Mechanical Properties Of Titanium Alloys, A Dehghan-Manshadi, Mark H. Reid, R J. Dippenaar Jan 2010

Effect Of Microstructural Morphology On The Mechanical Properties Of Titanium Alloys, A Dehghan-Manshadi, Mark H. Reid, R J. Dippenaar

Faculty of Engineering - Papers (Archive)

Different morphologies of α+β microstructures were obtained in a commercial Ti-6Al-4V alloy by cooling at different rates from the single β-phase region into the two phase region. The effect of such morphologies on mechanical properties was studied using hot compression tests in a Gleeble thermomechanical simulator. A variety of complex morphologies could be obtained since the cooling rate has a significant influence on the β to α phase transformation and the resulting morphological development. While most of the β phase transformed to colonies of α at high cooling rates, it was possible to obtain a complex mixture of a colonies, …


A Study Of The Continous Cooling Behaviour And Effect Of Preheat And Interpass Temperature On The Haz Of High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Mark Callaghan, Nathan Larkin, Robert Scott, Robert De Jong, Huijun Li, John Norrish Jan 2010

A Study Of The Continous Cooling Behaviour And Effect Of Preheat And Interpass Temperature On The Haz Of High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Mark Callaghan, Nathan Larkin, Robert Scott, Robert De Jong, Huijun Li, John Norrish

Faculty of Engineering - Papers (Archive)

In this study, the continuous cooling phase transformation behaviour of a quenched and tempered armour steel was investigated. A continuous cooling transformation diagram was constructed providing valuable information for predicting microstructural evolution and mechanical properties at different cooling rates during actual welding fabrication. Welding trials were carried out utilising flux-cored arc welding technique in combination with an austenitic stainless steel consumable. The effect of various preheat and interpass temperatures on cooling rate and consequently on the heat affected zone microstructure and mechanical properties of multipass welds were investigated.


Buoyancy-Driven Flows In Pipelines - Effect On Hydrostatic Test Measurements, Ajit Godbole, Paul Cooper, Phillip Venton, John Hough Jan 2010

Buoyancy-Driven Flows In Pipelines - Effect On Hydrostatic Test Measurements, Ajit Godbole, Paul Cooper, Phillip Venton, John Hough

Faculty of Engineering - Papers (Archive)

No abstract provided.


The Effect Of Non-Linear Mooring Stiffness On The Vortex-Induced Motion Of Cylindrical Structures, Brad Stappenbelt Jan 2010

The Effect Of Non-Linear Mooring Stiffness On The Vortex-Induced Motion Of Cylindrical Structures, Brad Stappenbelt

Faculty of Engineering - Papers (Archive)

Mooring systems employed for floating structures commonly result in non-linear load-excursion characteristics. The non-linear stiffness and the subsequent amplitude-dependent natural frequency influence the vortex-induced motion of the structure. The application of linear stiffness vortex-induced motion modelling and experimental data has been shown to produce significant uncertainties regarding the onset and vortex-induced response prediction of catenary moored cylindrical structures (Bjarke et al. 2003; Dijk et al. 2003). In the present study, the two-degree of freedom vortex-induced motion of non-linearly compliant elastically mounted rigid cylinders was experimentally investigated. Specifically, third-order polynomial hard-spring stiffness, typical of catenary moorings was considered. The linear and …


Effect Of Nano-Sized Particles On Bond Strength In Accumulative Roll Bonding, Lihong Su, Cheng Lu, Tim Mcneice, A K. Tieu Jan 2010

Effect Of Nano-Sized Particles On Bond Strength In Accumulative Roll Bonding, Lihong Su, Cheng Lu, Tim Mcneice, A K. Tieu

Faculty of Engineering - Papers (Archive)

Effect of nano-particles on bond strength of aluminium alloy 5050 produced by ARB was investigated. Experimental results indicated that nano-particles can significantly enhance the bond strength of aluminium alloys. Several kinds of nanoparticles with different particle size were compared. The hardness of the particles and the particle size are the two factors that decide the strengthening effect.The results showed that 50 nm Al2O3 particles have the best strengthening effect.


A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou Jan 2010

A Sign Of Field-Induced First Order Magnetic State Transition And Giant Reversible Magnetocaloric Effect In Cobalt Hydroxide Nanosheets, Precious Shamba, Rong Zeng, J Q Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

We report the synthesis of β−Co(OH)2 nanosheets using microwave assisted hydrothermal and conventional chemical reaction methods. A magnetic transition at an onset temperature, T1 ~ 96 K, and a sign of antiferromagnetic state transition at the Néel temperature, TN=9~10 K, can be determined from M-T curves and M-H curves magnetic properties investigation. It is found that a sign of field-induced first order transition below 9 K, act as a role of reversing the magnetocaloric effect from negative to positive value. The large reversible magnetic-entropy change (∆SM) of 17 J/kg K around 11 K for …