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Full-Text Articles in Engineering
Effect Of Holding Temperature And Time On Ferrite Formation In Dual Phase Steel Produced By Strip Casting, Zhiping Xiong, Andrii Kostryzhev, Nicole Stanford, Elena V. Pereloma
Effect Of Holding Temperature And Time On Ferrite Formation In Dual Phase Steel Produced By Strip Casting, Zhiping Xiong, Andrii Kostryzhev, Nicole Stanford, Elena V. Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
Conventional dual phase (DP) steel (0.08C-0.81Si-1.47Mn-0.03Al, wt. %) was manufactured by the laboratory simulation of strip casting. The effect of holding temperature and time on microstructure evolution was studied using a quench-deformation dilatometer. Microstructures were observed using optical and scanning electron microscopy. The results showed that the nose temperature of ferrite phase field is around 650 °C. The kinetics of ferrite formation is fast within the first 100 s of holding at this temperature, and then formation of ferrite continues at a slower rate until it reaches the fraction corresponding to that defined by the lever rule. 70~80 % ferrite …
Study On Hot-Working Behavior Of High Carbon Steel / Low Carbon Steel Composite Material Using Processing Map, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen
Study On Hot-Working Behavior Of High Carbon Steel / Low Carbon Steel Composite Material Using Processing Map, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen
Faculty of Engineering and Information Sciences - Papers: Part A
The high carbon steel (HCS)/low carbon steel (LCS) laminated composite made by centrifugal casting technology was subjected to hot compression tests on Gleeble 3500 thermomechanical simulator in a range of temperatures (800-1100 oC) and strain rates (0.02-10 s-1). The hot-working behavior of the laminate was characterised by analysing the flow stress-strain curves and constructing the processing map based on dynamic materials model via superimposing efficiency of power dissipation and flow instability maps. The safe and unsafe processing conditions were identified in the processing map which was validated by microstructural examinations. Banded microstructure and micro-shear cracks occurred in the unsafe domains …
A Study Surface Layer And Hardness Produced By Induction Hardened S45c Steel, Alain Parisianto, Rosfian Dahar, Huijun Li, Syamsul Hadi
A Study Surface Layer And Hardness Produced By Induction Hardened S45c Steel, Alain Parisianto, Rosfian Dahar, Huijun Li, Syamsul Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
A cylinder of Carbon Steel S45C with a ferrite and pearlite structure was analysed to improve the hardness and surface layer as well as the toughness. Accordingly, it is important to undertake a heat treatment process for the hardness and surface layer of this steel. The heat teatment process was carried out using induction heating with five different temperatures of 800°C, 900°C, 1000°C, 1100°C and 1200 °C followed by water quenching with certain cooling speed. The chemical compositions and microstructures of these samples were characterized by spectrometer and optical microscopy. The microhardness of the samples was measured and the surface …
Shape Optimization Of Thin-Walled Steel Sections Using Graph Theory And Aco Algorithm, Pezhman Sharafi, Lip H. Teh, Muhammad N. S Hadi
Shape Optimization Of Thin-Walled Steel Sections Using Graph Theory And Aco Algorithm, Pezhman Sharafi, Lip H. Teh, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents an intuitive procedure for the shape and sizing optimizations of open and closed thin-walled steel sections using the graph theory. The goal is to find shapes of optimum mass and strength (bi-objectives). The shape optimization of open sections is treated as a multi-objective all-pairs shortest path problem, while that of closed sections is treated as a multi-objective minimum mean cycle problem. The sizing optimization of a predetermined shape is treated as a multi-objective single-pair shortest path problem. Multi-colony ant algorithms are formulated for solving the optimization problems. The verification and numerical examples involving the shape optimizations of …
Constitutive Analysis For Hot Deformation Behaviour Of Novel Bimetal Consisting Of Pearlitic Steel And Low Carbon Steel, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Huijun Li, Sihai Jiao, Jianzhong Xu, Xiaoming Zhang, Jingtao Han, Dengfu Chen
Constitutive Analysis For Hot Deformation Behaviour Of Novel Bimetal Consisting Of Pearlitic Steel And Low Carbon Steel, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Huijun Li, Sihai Jiao, Jianzhong Xu, Xiaoming Zhang, Jingtao Han, Dengfu Chen
Faculty of Engineering and Information Sciences - Papers: Part A
To understand the high temperature flow behaviour of a novel pearlitic steel (PS) and low carbon steel (LCS) bimetal, hot compression tests in a wide range of temperature and strain rate were conducted on a Gleeble 3500 thermo mechanical simulator, and the constitutive model was developed based on the experimental data. The measured true stress-strain curves exhibited three types of variation patterns, which are (i) a plateau type, (ii) single peak type and (iii) multi peaks type. These patterns well displayed the effects of the deformation temperature, strain rate and plastic strain on the flow behaviour of the bimetal. By …
Crack Healing In A Low-Carbon Steel Under Hot Plastic Deformation, Hailiang Yu, Xianghua Liu, Xinwen Li, Ajit R. Godbole
Crack Healing In A Low-Carbon Steel Under Hot Plastic Deformation, Hailiang Yu, Xianghua Liu, Xinwen Li, Ajit R. Godbole
Faculty of Engineering and Information Sciences - Papers: Part A
The behavior of internal crack healing in low-carbon steel samples undergoing hot plastic deformation was investigated using the MMS 200 thermo-mechanical simulator. The characterization of cracks after plastic deformation was analyzed using scanning electron microscopy under different heating temperatures, reduction ratios, numbers of deformation passes, strain rates, and holding time durations. It was found that the degree of crack healing increases with increasing heating temperature, reduction ratio, and holding time duration, and with decreasing number of deformation passes and strain rate.
Effect Of A Grain-Refined Microalloyed Steel Substrate On The Formation Mechanism Of A Tight Oxide Scale, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou, Qingxue Huang
Effect Of A Grain-Refined Microalloyed Steel Substrate On The Formation Mechanism Of A Tight Oxide Scale, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou, Qingxue Huang
Faculty of Engineering and Information Sciences - Papers: Part A
The formation mechanism of tight oxide scale on the microalloyed steel was investigated at temperatures of 550-850 °C in dry air. Microstructural characterisations reveal that the spallation of oxide scale dominates at the centre of coarse grains on the oxidation initiation. The fine-grained steel improves the adhesive properties of oxide scale by enhanced grain-boundary diffusion. The lower activation energy and higher oxidation rate accelerate cation/anion migration along grain boundaries, leading to high magnetite content in the oxide scale. The approach by grain refinement at initial oxidation has been proposed to generate the pickle-free tight oxide scale.
Computational Analysis Of Compressive Strain Hardening Exponents Of Bimetal With Pearlitic Steel And Low Carbon Steel, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Jingtao Han
Computational Analysis Of Compressive Strain Hardening Exponents Of Bimetal With Pearlitic Steel And Low Carbon Steel, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Jingtao Han
Faculty of Engineering and Information Sciences - Papers: Part A
The compressive strain hardening behaviour of a novel bimetal with pearlitic steel and low carbon steel was investigated by computational analysis based on the isothermal compression tests in a wide range of deformation temperature and strain rate. The Hollomon's equation was employed to calculate the strain hardening exponent (SHE) with the assistance of mathematical manipulation. The result shows that the logarithmic relationship between the flow stress and plastic strain of the bimetal is highly non-linear, which results in the variation of the SHE of the bimetal. This variation reflects the dynamic competition between the strain hardening and softening mechanism by …
Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong
Effects Of Temperature And Strain Rate On Microstructure And Mechanical Properties Of High Chromium Cast Iron/Low Carbon Steel Bimetal Prepared By Hot Diffusion-Compression Bonding, Xingjian Gao, Zhengyi Jiang, Dongbin Wei, Sihai Jiao, Dengfu Chen, Jianzhong Xu, Xiaoming Zhang, Dianyao Gong
Faculty of Engineering and Information Sciences - Papers: Part A
The objective of this study is to develop a hot diffusion-compression bonding process for cladding low carbon steel (LCS) to high chromium cast iron (HCCI) in solid-state. The influence of temperature (950-1150 degrees C) and strain rate (0.001-1 s (1)) on microstructure, hardness and bond strength of the HCCI/LCS bimetal were investigated. The interface microstructure reveals that the unbonded region can only be found for 950 degrees C due to lack of diffusion, while the intergrowth between the constituent metals occurred at and above 1100 degrees C. When bonding temperature increases to 1150 degrees C, a carbide-free zone was observed …
Cellular Automaton Simulation Of Hot Deformation Of Trip Steel, Ying Zhi, Xianghua Liu, Hailiang Yu
Cellular Automaton Simulation Of Hot Deformation Of Trip Steel, Ying Zhi, Xianghua Liu, Hailiang Yu
Faculty of Engineering and Information Sciences - Papers: Part A
The recrystallization process of hot deformed austenite of TRIP steel was predicted using Cellular Automaton (CA) combined with the principles of physical metallurgy. A model was developed for prediction of the dynamic and static recrystallization microstructure evolution and properties of hot deformed austenite for TRIP steel. The theoretical modeling of recrystallization was based on dislocation density. The microstructure evolution of austenite recrystallization of TRIP steel (such as the grain shape and size, volume fraction, kinetics curve of recrystallization) was predicted both visually and quantitatively. The distribution and variation of the dislocation density and flow stress were also obtained, and the …
Influence Of Pallets On The Behaviour And Design Of Steel Drive-In Racks, Benoit Gilbert, Lip H. Teh, Romain X. Badet, Kim Rasmussen
Influence Of Pallets On The Behaviour And Design Of Steel Drive-In Racks, Benoit Gilbert, Lip H. Teh, Romain X. Badet, Kim Rasmussen
Faculty of Engineering and Information Sciences - Papers: Part A
This paper analyses the influence of horizontal bracing restraints provided by the friction between pallet bases and rail beams on the static behaviour and design of steel drive-in storage racks. The pallet bracing restraints are shown to significantly influence the structural behaviour of the rack, and their effect on the bending moment distribution of the uprights is studied in the paper. The 2D single upright model proposed by Godley is improved in this study by including the restraints provided by the plan flexural stiffness of the rail beams and the friction between the pallets and rail beams. The improved 2D …
Numerical Analysis Of High-Strength Concrete-Filled Steel Tubular Slender Beam-Columns Under Cyclic Loading, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi
Numerical Analysis Of High-Strength Concrete-Filled Steel Tubular Slender Beam-Columns Under Cyclic Loading, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
The effects of cyclic local buckling on the behavior of concrete-filled steel tubular (CFST) slender beam-columns under cyclic loading were approximately considered in existing analytical methods by modifying the stress– strain curve for the steel tube in compression. These methods, however, cannot simulate the progressive cyclic local buckling of the steel tubes. This paper presents a new efficient numerical model for predicting the cyclic performance of high strength rectangular CFST slender beam-columns accounting for the effects of progressive cyclic local buckling of steel tube walls under stress gradients. Uniaxial cyclic constitutive laws for the concrete core and steel tubes are …
Effect Of Austenite Deformation Temperature On Nb Clustering And Precipitation In Microalloyed Steel, E V Pereloma, A G Kostryzhev, A Alshahrani, C Zhu, J M. Cairney, C R. Killmore, S P. Ringer
Effect Of Austenite Deformation Temperature On Nb Clustering And Precipitation In Microalloyed Steel, E V Pereloma, A G Kostryzhev, A Alshahrani, C Zhu, J M. Cairney, C R. Killmore, S P. Ringer
Faculty of Engineering and Information Sciences - Papers: Part A
The effect of thermomechanical processing conditions on Nb clustering and precipitation in both austenite and ferrite in a Nb-Ti microalloyed steel was studied using electron microscopy and atom probe tomography. A decrease in the deformation temperature increased the Nb-rich precipitation in austenite and decreased the extent of precipitation in ferrite. Microstructural mechanisms that explain this variation are discussed. 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Effect Of Niobium Clustering And Precipitation On Strength Of A Nbti-Microalloyed Ferritic Steel, Andrii Kostryzhev, Abdullah Alshahrani, Chen Zhu, Julie Cairney, Simon Peter Ringer, Chris Killmore, E V. Pereloma
Effect Of Niobium Clustering And Precipitation On Strength Of A Nbti-Microalloyed Ferritic Steel, Andrii Kostryzhev, Abdullah Alshahrani, Chen Zhu, Julie Cairney, Simon Peter Ringer, Chris Killmore, E V. Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
The microstructure-property relationship of an NbTi-microalloyed ferritic steel was studied as a function of thermo-mechanical schedule using Gleeble 3500 simulator, optical and scanning electron microscope, and atom probe tomography.
Surface Treatment Evaluation Of Induction Hardened And Tempered 1045 Steel, Alain Kusmoko, Druce P. Dunne, Rosfian Dahar, Huijun Li
Surface Treatment Evaluation Of Induction Hardened And Tempered 1045 Steel, Alain Kusmoko, Druce P. Dunne, Rosfian Dahar, Huijun Li
Faculty of Engineering and Information Sciences - Papers: Part A
Rod-shaped samples of SAE-AISI grade 1045 steel with a ferrite and pearlite structure in the as received condition were subjected to induction hardening to increase the hardness of the surface layer. The heat treatment process was carried out using induction heating with five different peak temperatures: 8000C, 9000C, 10000C, 11000C and 1200 0C for 2 s, before water quenching. The chemical composition and the microstructures of these samples were characterized by spectrometry and optical microscopy. The microhardness of the surface of each samples was measured and preliminary tensile testing was conducted. The results showed the formation of a significant hardened …
Nonlinear Analysis Of Axially Loaded Cicular Concrete-Filled Stainless Steel Tubular Short Columns, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi
Nonlinear Analysis Of Axially Loaded Cicular Concrete-Filled Stainless Steel Tubular Short Columns, Vipulkumar Patel, Qing Quan Liang, Muhammad N. S Hadi
Faculty of Engineering and Information Sciences - Papers: Part A
The experiments indicate that stainless steels in tension deform plastically more than stainless steels in compression. Therefore, the strain hardening of stainless steels in compression is much faster than that of stainless steels in tension. The full-range two-stage constitutive model for stainless steels assumes that stainless steels follow the same stress-strain behavior in compression and tension, which may underestimate the compressive strength of stainless steel tubes. This paper presents a fiber element model incorporating the recently developed full-range three-stage stress-strain relationships based on experimentally observed behavior for stainless steels for the nonlinear analysis of circular concrete-filled stainless steel tubular (CFSST) …
Role Of Microstructure In Susceptibility To Hydrogen Embrittlement Of X70 Microalloyed Steel, Daniel Hejazi, Ahmed Saleh, Ayesha Haq, Druce Dunne, Andrzej Calka, Azdiar A. Gazder, Elena V. Pereloma
Role Of Microstructure In Susceptibility To Hydrogen Embrittlement Of X70 Microalloyed Steel, Daniel Hejazi, Ahmed Saleh, Ayesha Haq, Druce Dunne, Andrzej Calka, Azdiar A. Gazder, Elena V. Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
The effect of phases and steel processing on hydrogen uptake (diffusible and residual), surface and internal damage were evaluated using optical and scanning electron microscopy. The results have shown the fastest formation of blisters in ferrite-pearlite microstructure of strip, followed by equaixed ferrite-pearlite microstructure in normalised condition, then by ferrite-bainite microstructure. No blistering was observed in heat affected zone samples for up to 24 hrs charging. Analysis of hydrogen-induced cracking using electron back scattering diffraction has revealed that crack propagation has predominantly intragranular character without a clear preference on {001}, {110}, {112} and {123} planes and is independent of the …
Wear Mode Map Evaluation Of Induction Hardened 4140 And Carburised 8617h Steels On 1040 Steel, Alain Kusmoko, Alan Crosky
Wear Mode Map Evaluation Of Induction Hardened 4140 And Carburised 8617h Steels On 1040 Steel, Alain Kusmoko, Alan Crosky
Faculty of Engineering and Information Sciences - Papers: Part A
This study was undertaken to evaluate the likely effect on the wear rate of changing the pinion material in a rack and pinion steering box from carburised SAE-AISI grade 8617 H steel to induction hardened SAE-AISI grade 4140 steel. Accordingly, pin-on-disc unlubricated wear tests were conducted using carburised 8617 H pins and through hardened 4140 pins. The surface hardness of the pins was approximately 60 HRC for both materials. The discs were made of SAE-AISI grade 1040 steel through hardened to a hardness of 45 HRC. The tests were conducted using a load of 2.2 kg and a rotational speed …
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
The Response Of Axially Restrained Non-Composite Steel-Concrete-Steel Sandwich Panels Due To Large Impact Loading, Alex M. Remennikov, Sih Ying Kong, Brian Uy
Faculty of Engineering and Information Sciences - Papers: Part A
In conventional steel-concrete-steel (SCS) construction, the external steel plates are connected to the concrete infill by welded shear stud connectors. This paper describes a programme of experimental and numerical investigations on reduced-scale non-composite SCS panels with axially restrained connections. The experimental results have demonstrated that the non-composite SCS panels are capable of developing enhanced load-carrying capacity through the tensile membrane resistance of the steel faceplates. This type of construction was found to exhibit highly ductile response and be able to sustain large end rotations of up to 18° without collapse. High fidelity finite element models for SCS panels under impact …
Development Of Safe Optimized Welding Procedures For High Strength Q&T Steel Welded With Austenitic Consumables, Lenka Kuzmikova, Huijun Li, John Norrish, Zengxi Stephen Pan, Nathan Larkin
Development Of Safe Optimized Welding Procedures For High Strength Q&T Steel Welded With Austenitic Consumables, Lenka Kuzmikova, Huijun Li, John Norrish, Zengxi Stephen Pan, Nathan Larkin
Faculty of Engineering and Information Sciences - Papers: Part A
High strength quenched and tempered (Q&T) steels offer obvious economic benefits originating from their advantageous strength to price and weight ratios. These steels are usually welded using ferritic consumables and for this combination the risk of hydrogen assisted cold cracking (HACC) is high. The use of austenitic stainless steel (ASS) consumables has great potential to significantly improve this issue. Yet, there are no guidelines for determination of safe level of preheat for welding ferritic steels with ASS consumables. For this reason manufacturers adopt this parameter from procedures developed for conventional ferritic consumables thus significantly limiting the benefits ASS consumables are …
Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng
Behavior Of Hybrid Frp-Concrete-Steel Double-Skin Tubular Columns With A Square Outer Tube And A Circular Innert Tube Subjected To Axial Compression, Tao Yu, J G. Teng
Faculty of Engineering and Information Sciences - Papers: Part A
Hybrid fiber-reinforced polymer (FRP) concrete steel, double skin tubular columns (DSTCs) are a new form of hybrid columns. The most common sectional form of hybrid DSTCs consists of a layer of concrete sandwiched between a circular inner steel tube and a circular outer FRP tube whose fiber directions are close to the hoop detection to provide effective confinement to the concrete. Much recent research has been conducted on circular hybrid DSTCs, which has demonstrated that the combination of the three constituent materials leads to several advantages not available with existing forms of columns. In practical applications, for aesthetic and other …
Net Section Tension Capacity Of Cold-Reduced Sheet Steel Angle Braces Bolted At One Leg, Lip H. Teh, Benoit P. Gilbert
Net Section Tension Capacity Of Cold-Reduced Sheet Steel Angle Braces Bolted At One Leg, Lip H. Teh, Benoit P. Gilbert
Faculty of Engineering and Information Sciences - Papers: Part A
This paper examines the accuracy of equations specified by the North American and Australasian steel structures codes for determining the net section tension capacity of a cold-formed steel angle brace bolted at one leg. The configurations tested in the laboratory include single equal angle, single unequal angle bolted at the wider leg, single unequal angle bolted at the narrow leg, double angles, and alternate angles. The steel materials used in the experiment are among those with the lowest ductility for which nominal tensile strength is permitted by cold-formed steel design codes to be fully utilized in structural design calculations. Based …
Analysis Of Elemental Segregation In A Microalloyed Cast Steel, Jingwei Zhao, Zhengyi Jiang, Dongbin Wei
Analysis Of Elemental Segregation In A Microalloyed Cast Steel, Jingwei Zhao, Zhengyi Jiang, Dongbin Wei
Faculty of Engineering and Information Sciences - Papers: Part A
Quantitative investigation is made on the elemental segregation in different zones of a heavy microalloyed cast steel by energy dispersive X-ray spectroscopy. It is demonstrated that C shows serious segregation tendency than that of Mn and Si, and the degree of C segregation in the surface zone is higher than that in the central zone. C enrichment is generally observed at both dendrite arm and grain boundaries, and more C segregation at dendrite arm boundary in contrast to that at grain boundary is found in this steel. The distribution of C concentration shows a decreased trend from root to tip …
Shear Lag And Eccentricity Effects Of Bolted Connections In Cold-Formed Steel Sections, Lip H. Teh, Veysel Yazici
Shear Lag And Eccentricity Effects Of Bolted Connections In Cold-Formed Steel Sections, Lip H. Teh, Veysel Yazici
Faculty of Engineering and Information Sciences - Papers: Part A
This paper examines the "three factors" approach previously presented by the senior author for determining the net section efficiency of a bolted cold-formed steel open profile. One objective is to ascertain that the net section efficiency is governed by three factors: the in-plane shear lag associated with stress concentration around a bolt hole that is also present in a flat sheet, the out-of-plane shear lag that is also present in a bi-symmetric I-section bolted at the flanges only, and the bending moment arising from the connection eccentricity with respect to the neutral axis. This paper presents the test results of …
Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma
Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
The effect of deformation temperature on Nb solute clustering, precipitation and the kinetics of austenite recrystallisation were studied in a steel containing 0.081C–0.021Ti–0.064 Nb (wt%). Thermo-mechanical processing was carried out using a Gleeble 3500 simulator. The austenite microstructure was studied using a combination of optical microscopy, transmission electron microscopy, and atom probe microscopy, enabling a careful characterisation of grain size, as well as Nb-rich clustering and precipitation processes. A correlation between the austenite recrystallisation kinetics and the chemistry, size and number density of Nb-rich solute atom clusters, and NbTi(C,N) precipitates was established via the austenite deformation temperature. Specifically, we have …
Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma
Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
An investigation into influence of the austenitising temperature and the austenite deformation temperature on Nb precipitation and recrystallisation kinetics was carried out for a steel containing 0.081C-0.021Ti-0.064Nb (wt. %). The austenite grain structure was correlated to the dispersive properties of Nb atom clustering and precipitation. Irrespective of the austenitising temperature, deformation to 0.75 strain at 1075 °C produced a fully recrystallised microstructure. After deformation at 975 °C, only partial recrystallisation was observed in the samples austenitised at higher temperature, whereas samples austenitised at lower temperature were fully recrystallised. The influence of solute drag and particle pinning effects on the recrystallisation …
Ebsd Observations Of Recrystallisation And Tensile Deformation In Twinning Induced Plasticity Steel, Ahmed A. Saleh, Azdiar A. Gazder, Elena Pereloma
Ebsd Observations Of Recrystallisation And Tensile Deformation In Twinning Induced Plasticity Steel, Ahmed A. Saleh, Azdiar A. Gazder, Elena Pereloma
Faculty of Engineering and Information Sciences - Papers: Part A
The microstructure evolution of cold-rolled and isochronally annealed Fe-24Mn-3Al-2Si-1Ni-0.06C twinning induced plasticity steel was investigated by electron back-scattering diffraction (EBSD). Deformation behaviour of a fully recrystallised sample was tracked in a selected area as a function of the true strain using a combination of interrupted tensile testing and EBSD. The results show that the cold rolled microstructure contained a large fraction of primary and secondary twins as well as remnants of annealing twins carried over from the prior hot rolling stage. A novel deconstruction technique was applied to a partially recrystallised sample in order to separate the microstructure into deformed, …
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Enhancing Impact Fracture Toughness And Tensile Properties Of A Microalloyed Cast Steel By Hot Forging And Post-Forging Heat Treatment Processes, Jingwei Zhao, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the present work, the effects of hot forging and post-forging heat treatment on the impact fracture toughness and tensile properties of a microalloyed cast steel were investigated. Mechanical tests were used to evaluate the room temperature impact fracture toughness and tensile properties of the steel. The resulting microstructures were analysed by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The extraction replica technology was used to investigate the characterisation of complex precipitates formed during heat treatment. The obtained results showed that the coarse-grained microstructure of the forged specimen was significantly refined after post-forging heat treatment. …
Enhancing Mechanical Properties Of A Low-Carbon Microalloyed Cast Steel By Controlled Heat Treatment, Jingwei Zhao, Jeong Hun Lee, Yong Woo Kim, Zhengyi Jiang, Chong Soo Lee
Enhancing Mechanical Properties Of A Low-Carbon Microalloyed Cast Steel By Controlled Heat Treatment, Jingwei Zhao, Jeong Hun Lee, Yong Woo Kim, Zhengyi Jiang, Chong Soo Lee
Faculty of Engineering and Information Sciences - Papers: Part A
In the present work, detailed studies were made on the optimization of microstructure and mechanical properties of a low-carbon microalloyed cast steel through control of heat treatment conditions. Specimens were austenitized at temperatures ranging from 950 to 1200 °C for 2 h followed by different cooling methods (furnace, air and water). For analyzing the effect of holding time on mechanical properties, some cast specimens were austenitized at 1100 °C for different times followed by furnace cooling. After heat treatment, mechanical tests were employed to evaluate the room temperature Charpy impact and tensile properties. The characterization of complex precipitates formed during …
Tribological Properties Of Magnetite Precipitate From Oxide Scale In Hot-Rolled Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Dongbin Wei, Cunlong Zhou, Qingxue Huang, Daijun Yang
Tribological Properties Of Magnetite Precipitate From Oxide Scale In Hot-Rolled Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Dongbin Wei, Cunlong Zhou, Qingxue Huang, Daijun Yang
Faculty of Engineering and Information Sciences - Papers: Part A
Nano-magnetite (Fe3O4) particles have a potential to lead to the formation of lubrication tribofilm that reduces the friction and wear in hot steel strip rolling. In this paper, an attempt to fabricate the oxide film with magnetite precipitates from thermally-grown wustite (Fe1-xO) layer during isothermal cooling of low carbon microallyed steel, was obtained. The precipitation behaviors were investgated on Gleeble 3500 thermo-mechanical simulator under the humid air with water vaour content of 19.5 per vol percent. Several types of magnetite precipitates were examined using scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analysis. The tribological …