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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 …
Superconductivity In Lafeas1-Xpxo: Effect Of Chemical Pressures And Bond Covalency, Cao Wang, Shuai Jiang, Qian Tao, Zhi Ren, Yuke Li, Linjun Li, Chunmu Feng, Jianhui Dai, Guanghan Cao, Zhu-An Xu
Superconductivity In Lafeas1-Xpxo: Effect Of Chemical Pressures And Bond Covalency, Cao Wang, Shuai Jiang, Qian Tao, Zhi Ren, Yuke Li, Linjun Li, Chunmu Feng, Jianhui Dai, Guanghan Cao, Zhu-An Xu
Faculty of Engineering - Papers (Archive)
We report the realization of superconductivity by an isovalent doping with phosphorus in LaFeAsO. X-ray diffraction shows that, with the partial substitution of P for As, the Fe2As2 layers are squeezed while the La2O2 layers are stretched along the c-axis. Electrical resistance and magnetization measurements show emergence of bulk superconductivity at ∼ 10K for the optimally doped LaFeAs1−xPxO (x=0.25–0.3). The upper critical field at zero temperature is estimated to be 27T, much higher than that of the LaFePO superconductor. The occurrence of superconductivity is discussed in terms of chemical pressures and bond covalency
Effect Of Zn Doping On Magnetic Order And Superconductivity In Lafeaso, Yuke Li, Xiao Lin, Qian Tao, Cao Wang, Tong Zhou, Linjun Li, Qingbo Wang, Mi He, Guanghan Cao, Zhu-An Xu
Effect Of Zn Doping On Magnetic Order And Superconductivity In Lafeaso, Yuke Li, Xiao Lin, Qian Tao, Cao Wang, Tong Zhou, Linjun Li, Qingbo Wang, Mi He, Guanghan Cao, Zhu-An Xu
Faculty of Engineering - Papers (Archive)
We report Zn-doping effect in the parent and F-doped LaFeAsO oxy-arsenides. Slight Zn doping in LaFe1−xZnxAsO drastically suppresses the resistivity anomaly around 150K associated with the antiferromagnetic (AFM) spin density wave (SDW) in the parent compound. The measurements of magnetic susceptibility and thermopower confirm further the effect of Zn doping on AFM order. Meanwhile Zn doping does not affect or even enhances the Tc of LaFe1−xZnxAsO0.9F0.1, in contrast to the effect of Zn doping in high-Tc cuprates. We found that the solubility of Zn content (x) is limited to less than 0.1 in both systems and further Zn doping (i.e. …
Bauschinger Effect In Nb And V Alloyed Line-Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Bauschinger Effect In Nb And V Alloyed Line-Pipe Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis
Faculty of Engineering and Information Sciences - Papers: Part A
The UOE process is used for cold forming of large diameter steel line-pipes. Pipe strength has been found to increase (work hardening) or decrease (Bauschinger effect) after the UOE process compared to the plate depending on the steel grade, plate and pipe processing history. The steel chemistry, through the presence of microalloy precipitates, and prior processing, through the size and distribution of microalloy precipitates and presence of retained work hardening, affects the magnitude of the Bauschinger effect. In this paper the microstructures of two (Nb and Nb-V alloyed) steel plates, in terms of (Nb,V)(C,N) particle distributions and dislocation densities, have …
Dem Simulation Of Effect Of Confining Pressure On Ballast Behaviour, P K. Thakur, Buddhima Indraratna, Jayan Sylaja J S Vinod
Dem Simulation Of Effect Of Confining Pressure On Ballast Behaviour, P K. Thakur, Buddhima Indraratna, Jayan Sylaja J S Vinod
Faculty of Engineering - Papers (Archive)
In this paper, an attempt has been made to investigate the influence of confining pressure on deformation and degradation behaviourof railway ballast using the Discrete Element Method (DEM). A novel approach has been employed to model the two dimensionalprojection of field size ballast particles as cluster of bonded particles. Bonded particles are held together by a bond, and debonding isconsidered as particle breakage. A series of cyclic loading simulations using DEM were carried out on an assembly of angular ballast particles at different confining pressures (10 kPa to 240 kPa). The results highlight that the development of axial strain during …
Synthesis And Magnetorheological Effect Of Fe3o4-Tio2 Nanocomposite, Jianhong Wei, C J Leng, Xianzhou Zhang, Weihua Li, Z Y Liu, J Shi
Synthesis And Magnetorheological Effect Of Fe3o4-Tio2 Nanocomposite, Jianhong Wei, C J Leng, Xianzhou Zhang, Weihua Li, Z Y Liu, J Shi
Faculty of Engineering - Papers (Archive)
Aimed to obtain a material with improved rheological property, the Fe3O4-TiO2 nanocomposites were prepared by a modified sol-gel processing. The structure and morphology of the Fe3O4-TiO2 nanocomposites were examined by transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis and Fourier transform infrared spectroscopy (FT-IR) analysis, etc. The magnetic property and the magnetorheological properties of the coated particles were also examined in detail. The experimental results demonstrated that such materials exhibited favorable magnetorheological (MR) effect, and the MR performance of them were dependent on the relative content of TiO2 in …
Re-Entrant Ferromagnet Prmn2ge0.8si1.2: Magnetocaloric Effect, S X. Dou, Jianli Wang, Rong Zeng, Chung-Kiak Poh, Stewart J. Campbell, S J. Kennedy
Re-Entrant Ferromagnet Prmn2ge0.8si1.2: Magnetocaloric Effect, S X. Dou, Jianli Wang, Rong Zeng, Chung-Kiak Poh, Stewart J. Campbell, S J. Kennedy
Faculty of Engineering - Papers (Archive)
The structural and magnetic properties of the re-entrant ferromagnet PrMn2Ge0.8Si1.2 have been investigated by various experimental methods. Similar to the canonical re-entrant ferromagnet SmMn2Ge2, multiple magnetic phase transitions have been detected in PrMn2Ge0.8Si1.2 over the temperature range from 10 to 550 K with re-entrant ferromagnetism occurring around ∼ 54 K. The magnetocaloric effect has been measured in terms of the isothermal magnetocaloric entropy change and found to be positive at the re-entrant ferromagnetic transition with a maximum value of around 1.9 J/kg K at 58 K …
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 …