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Full-Text Articles in Engineering
Effect Of Pre-Straining And Bake Hardening On The Microstructure And Mechanical Properties Of Cmnsi Trip Steels, L. C. Zhang, I. B. Timokhina, A. La Fontaine, S. P. Ringer, P. D. Hodgson, E V. Pereloma
Effect Of Pre-Straining And Bake Hardening On The Microstructure And Mechanical Properties Of Cmnsi Trip Steels, L. C. Zhang, I. B. Timokhina, A. La Fontaine, S. P. Ringer, P. D. Hodgson, E V. Pereloma
Faculty of Engineering - Papers (Archive)
The effects of pre-straining and bake hardening on the mechanical behaviour and microstructural changes were studied in two CMnSi TRansformation-Induced Plasticity (TRIP) steels with different microstructures after intercritical annealing. The TRIP steels before and after pre-straining and bake hardening were characterised by X-ray diffraction, optical microscopy, transmission electron microscopy, three dimensional atom probe and tensile tests. Both steels exhibited discontinuous yielding behaviour and a significant strength increase with some reduction in ductility after pre-straining and bake hardening treatment. The following main microstructural changes are responsible for the observed mechanical behaviours: a decrease in the volume fraction of retained austenite, an …
Superconducting Properties Of Mgb2 Wire Using Ball Milled Low Purity Boron, Xun Xu, Jung Ho Kim, Yun Zhang, Yue Zhao, Matthew Rindfleisch, Michael Tomsic
Superconducting Properties Of Mgb2 Wire Using Ball Milled Low Purity Boron, Xun Xu, Jung Ho Kim, Yun Zhang, Yue Zhao, Matthew Rindfleisch, Michael Tomsic
Faculty of Engineering - Papers (Archive)
MgB2/Fe wire samples were prepared by using ball-milled 96% boron (B) powder with strong semi-crystalline phase. We observed samples that contained ball-milled 96% B in comparison with one made from as-supplied commercial 96% B, with the results showing a significant enhancement in the high field transport critical current density (Jct) due to small grain size and better reactivity. However, the inter-grain connectivity became worse, which could lead to poor Jct in low field and an increased level of disorder.
Microstructure And Mechanical Properties Of Thermomechanically Processed Trip Steel, Ilana B. Timokhina, Peter D. Hodgson, Hossein Beladi, E V. Pereloma
Microstructure And Mechanical Properties Of Thermomechanically Processed Trip Steel, Ilana B. Timokhina, Peter D. Hodgson, Hossein Beladi, E V. Pereloma
Faculty of Engineering - Papers (Archive)
The strengthening mechanism responsible for the unique combination of ultimate tensile strength and elongation in a multiphase Fe-0.2C-1.5Mn-1.2Si-0.3Mo-0.6Al-0.02Nb (wt%) steel was studied. The microstructures with different volume fractions of polygonal ferrite, bainite and retained austenite were simulated by controlled thermomechanical processing. The interrupted tensile test was used to study the bainitic ferrite, retained austenite and polygonal ferrite behaviour as a function of plastic strain. X-ray analysis was used to characterise the volume fraction and carbon content of retained austenite. Transmission electron microscopy was utilised to analyse the effect of bainitic ferrite morphology on the strain induced transformation of retained austenite …
Hydrothermal Synthesis And Optical, Magnetic And Supercapacitance Properties Of Nanoporous Cobalt Oxide Nanorodes, Guoxiu Wang, Xiaoping Shen, Josip Horvat, Bei Wang, Hao Liu, David Wexler, Jane Yao
Hydrothermal Synthesis And Optical, Magnetic And Supercapacitance Properties Of Nanoporous Cobalt Oxide Nanorodes, Guoxiu Wang, Xiaoping Shen, Josip Horvat, Bei Wang, Hao Liu, David Wexler, Jane Yao
Faculty of Engineering - Papers (Archive)
Nanoporous cobalt oxide nanorods were synthesized by a hydrothermal method. Transmission electron microscopy analysis showed that the individual Co3O4 nanorods have a nanoporous structure, consisting of the textured aggregations of nanocrystals. Optical properties of Co3O4 nanorods were characterized by Raman and UV−vis spectroscopy. Magnetic property measurement shows that Co3O4 nanorods have a low Néel transition temperature of 35 K. We observed quite significant exchange bias for nanoporous Co3O4 nanorods, indicating the existence of magnetic coupling between the nanocrystals in Co3O4 nanorods. When applied as electrode …
Applications Of Hydraulic Properties Models On Microscopic Flow In Unsaturated Porous Media, Thidarat Bunsri, Muttucumaru Sivakumar, Dharmappa Hagare
Applications Of Hydraulic Properties Models On Microscopic Flow In Unsaturated Porous Media, Thidarat Bunsri, Muttucumaru Sivakumar, Dharmappa Hagare
Faculty of Engineering - Papers (Archive)
Several existing equations for solving the non-linear soil-hydraulic properties are introduced and validated to field and laboratory measured data. Models for non-linear hydraulic properties of unsaturated porous media arise from statistical and mathematical fit through the measured data and they can be expressed in forms of unsaturated permeability versus either pressure head or volumetric moisture content. This paper presents the difference models: Gardner, Knuze et al., Haverkamp et al., van Genuchten and Saxton et al. for calculation of hydraulic properties coefficients, typicallyunsaturated permeability. The accurate and computational efficiency of these five existing models are evaluated for a series of study …
Mre Properties Under Shear And Squeeze Modes And Applications, Kristin Popp, Matthias Kroger, Weihua Li, Xianzhou Zhang, Prabuono B. Kosasih
Mre Properties Under Shear And Squeeze Modes And Applications, Kristin Popp, Matthias Kroger, Weihua Li, Xianzhou Zhang, Prabuono B. Kosasih
Faculty of Engineering - Papers (Archive)
Magnetorheological elastomers (MREs) are smart materials whose mechanical properties, like their modulus and elasticity, can be controlled by an external magnetic field. This feature has resulted in a number of novel applications, such as adaptive tuned dynamic vibration absorbers for suppressing unwanted vibrations over a wide frequency range. MRE-based devices operate in different modes, such as shear mode and squeeze mode; however, the study of mechanical performances of MREs under squeeze mode is very rare. This article aims to investigate MRE performances under both shear and squeeze modes. Experimental studies and simulations were conducted to analyze the MR effect in …
Thermal-Strain-Induced Enhancement Of Electromagnetic Properties Of Sic-Mgb2 Composites, Rong Zeng, S X. Dou, Lin Lu, Wenxian Li, Jung Ho Kim, Paul G. Munroe, Rongkun Zheng, S P. Ringer
Thermal-Strain-Induced Enhancement Of Electromagnetic Properties Of Sic-Mgb2 Composites, Rong Zeng, S X. Dou, Lin Lu, Wenxian Li, Jung Ho Kim, Paul G. Munroe, Rongkun Zheng, S P. Ringer
Faculty of Engineering - Papers (Archive)
The effect of thermal strain caused by the different thermal expansion coefficients (α) of the MgB2 and SiC phases on the electromagnetic properties was studied for SiC–MgB2 composite, which was made by premixing SiC and B, followed by Mg diffusion and reaction. Thermal strain in the MgB2 phase was demonstrated with x-ray diffraction, Raman spectroscopy, and transmission electron microscopy. In contrast to the common practice of improving the critical current density Jc and the upper critical field Hc2 of MgB2 through chemical substitution, by taking advantage of residual thermal strains, we …
Magnetic Properties And Magnetocaloric Effect Of (Mn1-Xnix)3sn2(X=0-0.5) Compounds, Rong Zeng, Lin Lu, Jung Ho Kim, Dongqi Shi, Hua-Kun Liu, S. X. Dou, Jianli Wang, Stewart J. Campbell, Zhaoxiang Wang, Y Li, Wenxian Li, M Y. Zhu, Chuanqi Feng
Magnetic Properties And Magnetocaloric Effect Of (Mn1-Xnix)3sn2(X=0-0.5) Compounds, Rong Zeng, Lin Lu, Jung Ho Kim, Dongqi Shi, Hua-Kun Liu, S. X. Dou, Jianli Wang, Stewart J. Campbell, Zhaoxiang Wang, Y Li, Wenxian Li, M Y. Zhu, Chuanqi Feng
Faculty of Engineering - Papers (Archive)
The effects of Ni substitution on the magnetic properties and magnetocaloric effect (MCE) of (Mn1−xNix)3Sn2 compounds (x = 0–0.5) have been investigated by x-ray diffraction and magnetization measurements. It was found that Ni substitution decreases the crystal cell volume and the magnetic transition temperatures compared with pure Mn3Sn2. The MCE for all samples has been calculated from the magnetization data in terms of the isothermal magnetic entropy change ΔSM. The maximum values of ΔSMmax at the magnetic phase transition temperatures resulting …