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Work Hardening Behaviors Of A Low Carbon Nb-Microalloyed Si-Mn Quenching-Partitioning Steel With Different Cooling Styles After Partitioning, Jun Zhang, Hua Ding, Chao Wang, Jingwei Zhao, Ting Ding Jan 2013

Work Hardening Behaviors Of A Low Carbon Nb-Microalloyed Si-Mn Quenching-Partitioning Steel With Different Cooling Styles After Partitioning, Jun Zhang, Hua Ding, Chao Wang, Jingwei Zhao, Ting Ding

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, the strain hardening behaviors of a low carbon Nb-microalloyed Si–Mn quenching–partitioning (Q–P) steel were investigated. The microstructures were analyzed by the scanning electron microscope (SEM) and transmission electron microscope (TEM). Mechanical tests were used to evaluate the room temperature tensile properties of the steel. The work hardening behaviors of the tested specimens were analyzed using the Hollomon approach. The results showed that a two-stage work hardening behavior was observed during deformation processes. In the first stage, for the quenched samples, martensite deforms plastically and the hardening exponent decreased. For the air-cooled samples, however, the carbide-free ferrite deforms …


Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem Jan 2013

Coupling Granular Activated Carbon Adsorption With Membrane Bioreactor Treatment For Trace Organic Contaminant Removal: Breakthrough Behaviour Of Persistent And Hydrophilic Compounds, Luong N. Nguyen, Faisal I. Hai, William E. Price, Jinguo Kang, Long D. Nghiem

Faculty of Engineering and Information Sciences - Papers: Part A

This study investigated the removal of trace organic contaminants by a combined membrane bioreactor - granular activated carbon (MBR-GAC) system over a period of 196 days. Of the 22 compounds investigated here, all six hydrophilic compounds with electron-withdrawing functional groups (i.e., metronidazole, carbamazepine, ketoprofen, naproxen, fenoprop and diclofenac) exhibited very low removal efficiency by MBR-only treatment. GAC post-treatment initially complemented MBR treatment very well; however, a compound-specific gradual deterioration of the removal of the above-mentioned problematic compounds was noted. While a 20% breakthrough of all four negatively charged compounds namely ketoprofen, naproxen, fenoprop and diclofenac occurred within 1000-3000 bed volumes …


Delivering Zero Carbon Homes In The Uk, Emma Elizabeth Heffernan, Wei Pan, Xi Liang Jan 2012

Delivering Zero Carbon Homes In The Uk, Emma Elizabeth Heffernan, Wei Pan, Xi Liang

Faculty of Engineering and Information Sciences - Papers: Part A

In the UK and internationally, a plethora of voluntary and mandatory energy efficiency standards for new buildings exist, with the common aim of mitigating the impact of new buildings on climate change. However, the take-up of voluntary schemes has been limited and, as a result, many governments have seen the need to introduce mandatory schemes through legislation; from 2016 all new build homes in England and Wales will be required to achieve zero carbon in regulated energy consumption. The international context of voluntary and mandatory building energy efficiency standards is examined through a review of the literature. The review is …


The Effect Of Chromium Addition On The Strain Ageing And Recrystallisation Behaviour Of Low Carbon Steel, Elena Pereloma, V Bata, Azdiar A. Gazder Jan 2012

The Effect Of Chromium Addition On The Strain Ageing And Recrystallisation Behaviour Of Low Carbon Steel, Elena Pereloma, V Bata, Azdiar A. Gazder

Faculty of Engineering and Information Sciences - Papers: Part A

The strain ageing and recrystallisation behaviour of conventional low carbon A06 steel was compared with those containing varying amounts of chromium (0.26, 0.52 and 0.74 wt.%). The results show that the A06 steel undergoes four stages of strain ageing: (i) the pinning by solute atoms of dislocations generated during pre-strain, (ii) the generation of fresh dislocations from grain boundaries, (iii) the onset of precipitation and, (iv) the inhibition of dislocation generation from grain boundaries due to pinning by carbon segregation. On the other hand, the chromium containing steels only exhibit the fIrst three stages of strain ageing. An approximately twofold …


Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price Jan 2012

Coupling Powdered Activated Carbon (Pac) Adsorption With Membrane Bioreactor (Mbr) Treatment For Enhanced Removal Of Trace Organics, Luong Nguyen, Faisal Ibney Hai, Long Nghiem, Jinguo Kang, William Price

Faculty of Engineering and Information Sciences - Papers: Part A

the occurrence of trace organics such as pesticides, pharmaceutically active compounds, natural and synthetic hormones as well as varous industrial compounds in the aquatic environment is of great concern due to their potential adverse effects on human health and those of other biota. Therefore, the removal of these compounds from wastewater is an important consideration to ensure safe drinking water and better protection of the environment. In the literature, several techniques have been explored for trace organics removal, namely, conventional activated sludge, membrane bioreactors (MBRs), and absorptioin. However it has been found that neither MBR nor activated carbon on its …


Recrystallisation Behaviour Of Low Carbon Steel With And Without Addition Of Chromium, Azdiar A. Gazder, Vladimir Bata, Sujoy S. Hazra, Elena V. Pereloma Jan 2012

Recrystallisation Behaviour Of Low Carbon Steel With And Without Addition Of Chromium, Azdiar A. Gazder, Vladimir Bata, Sujoy S. Hazra, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The effects of 0.74wt% Cr addition on the recrystallisation kinetics of low carbon (LC) steel was investigated using Vickers hardness testing, optical metallography and Electron Back- Scattering Diffraction (EBSD). Compared to the unalloyed steel, Cr addition significantly delays the time for recrystallisation and increases the JMAK pre-exponential factor (k) by an order of magnitude. During initial softening, EBSD returned similar orientations for nucleated and growing grain fractions in both steels. However with longer annealing times the micro-texture of recrystallised grains differs from their earlier counterparts. Overall, the effect of fine Cr carbides on grain boundary mobility in the LC-Cr steel …


Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez Jan 2011

Effect Of The Carbon Nanotube Surface Characteristics On The Conductivity And Dielectric Constant Of Carbon Nanotube/Poly(Vinylidene Fluoride) Composites, S A. Carabineiro, Manuel F. Pereira, J Nunes-Pereira, Cristina Caparrós, Vitor Sencadas, Senentxu Lanceros-Méndez

Faculty of Engineering and Information Sciences - Papers: Part A

Commercial multi-walled carbon nanotubes (CNT) were functionalized by oxidation with HNO3, to introduce oxygen-containing surface groups, and by thermal treatments at different temperatures for their selective removal. The obtained samples were characterized by adsorption of N2 at -196°C, temperature-programmed desorption and determination of pH at the point of zero charge. CNT/poly(vinylidene fluoride) composites were prepared using the above CNT samples, with different filler fractions up to 1 wt%. It was found that oxidation reduced composite conductivity for a given concentration, shifted the percolation threshold to higher concentrations, and had no significant effect in the dielectric response.


Hardness And Microstructural Gradients In The Heat Affected Zone Of Welded Low-Carbon Quenched And Tempered Steels, W Pang, N Ahmed, D Dunne Jan 2011

Hardness And Microstructural Gradients In The Heat Affected Zone Of Welded Low-Carbon Quenched And Tempered Steels, W Pang, N Ahmed, D Dunne

Faculty of Engineering and Information Sciences - Papers: Part A

This paper concentrates on the form of the hardness gradient in the heat affected zones (HAZs) produced by submerged arc welding of two low-carbon Q & T steels. The results show unequivocally that the gradient differs from that found in steels of lower carbon equivalent in that the peak HAZ hardness is displaced from the grain coarsened heat affected zone (GCHAZ) into the grain refined heat affected zone (GRHAZ). Weld thermal cycle simulation has been used to confirm the results obtained from actual welds and to clarify the cause of this unexpected phenomenon.


Australia Should Delay A Carbon Tax Until The Rest Of The World Acts, Henry Ergas Jan 2011

Australia Should Delay A Carbon Tax Until The Rest Of The World Acts, Henry Ergas

Faculty of Engineering and Information Sciences - Papers: Part A

The big question about the carbon tax is not whether it's a good or a bad idea in theory. The major issue is whether it makes sense for Australia to implement it at a time of great uncertainty, both in terms of economic outlook and the extent and nature of international action. To my mind a carbon tax is not desirable. Australia's prosperity is based on a resource endowment that is carbon intensive, both in terms of our mineral and our agricultural sector. Moreover, much of that carbon intensity is not amenable to technological quick-fixes. For instance, there is little …


Computational Intelligence For Carbon-Centric Computing, John Fulcher Jan 2010

Computational Intelligence For Carbon-Centric Computing, John Fulcher

Faculty of Engineering and Information Sciences - Papers: Part A

The focus of this paper is twofold: firstly we make a case for the use of Computational Intelligence (CI) techniques in the modelling and/or prediction of global weather, CO2 emissions, climate change and similar endeavours. CI exploits processes found in Nature, albeit by way of software simulations on digital computers (i.e. in silico), and excel in particular at pattern recognition and/or classification. Moreover, they are characterized as being non-algorithmic, bottom-up, data-driven, and learn-by-example. The second focus of this paper is to propose the use of carbonrather than silicon-based computing, specifically in the form of DNA (or molecular) computing. Notwithstanding the …


Development Of A Family Of High Strength Low Carbon Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Kristin R. Carpenter, Harold R. Kaul, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde Jan 2010

Development Of A Family Of High Strength Low Carbon Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Kristin R. Carpenter, Harold R. Kaul, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde

Faculty of Engineering and Information Sciences - Papers: Part B

The manufacture of high strength strip products in strip thicknesses less than 1.5mm is very challenging for the conventional hot and cold rolled processing routes. A range of Nb and Nb/V microalloyed steels have been successfully strip cast by the CASTRIP process enabling the development of a range of high strength Ultra-Thin Cast Strip (UCS) products. It was found that the CASTRIP process fully exploits the strengthening potential of the low C-Mn-Nb-(V) alloy design system. Substantial strengthening by microstructural hardening was provided by Nb. Retention of Nb and V in solid solution in hot rolled coils enabled further strengthening by …


Berkovich Indentation Of Diamondlike Carbon Coatings On Silicon Substrates, Ayesha J. Haq, Paul Munroe, Mark Hoffman, Phil Martin, Avi Bendavid Jan 2008

Berkovich Indentation Of Diamondlike Carbon Coatings On Silicon Substrates, Ayesha J. Haq, Paul Munroe, Mark Hoffman, Phil Martin, Avi Bendavid

Faculty of Engineering and Information Sciences - Papers: Part A

The deformation behavior of diamondlike carbon (DLC) coatings on silicon substrates induced by Berkovich indentation has been investigated. DLC coatings deposited by a plasma-assisted chemical vapor deposition technique were subjected to nanoindentation with a Berkovich indenter over a range of maximum loads from 100 to 300 mN. Distinct pop-ins were observed for loads greater than 150 mN. However, no pop-out was observed for the loads studied. The top surface of the indents showed annular cracks with associated fragmented material. The cross sections showed up to 20% localized reduction in thickness of the DLC coating beneath the indenter tip. Cracking, {111} …


Development Of Plain Carbon And Niobium Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Harold R. Kaul, Joshua Burg, Kristin R. Carpenter, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde Jan 2008

Development Of Plain Carbon And Niobium Microalloyed Ultra-Thin Cast Strip Products Produced By The Castrip® Process, Chris R. Killmore, Harold R. Kaul, Joshua Burg, Kristin R. Carpenter, James G. Williams, Daniel G. Edelman, Peter C. Campbell, Walter N. Blejde

Faculty of Engineering and Information Sciences - Papers: Part B

The CASTRIP facility at Nucor Steel's Crawfordsville, Indiana plant is the world's first commercial installation for production of Ultra-Thin Cast Strip (UCS), via twin-roll strip casting. The facility has been producing plain, low-carbon sheet steel since 2002, with a range of structural grades available. The paper outlines some of the main parameters that influence the final microstructure and resultant mechanical properties of plain, low carbon UCS steels that have been recently made by the CASTRIP process, and then describes new Nb microalloyed UCS products that have been made in the CASTRIP process, significantly expanding the range of thin high strength …


A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill Jan 2007

A Polyhedral Model For Carbon Nanotubes, Barry Cox, James Hill

Faculty of Engineering and Information Sciences - Papers: Part A

A new structural model accounts for the curvature inherent in their cylindrical shape.


Atomic Observations Of Warm Rolled Low Carbon Steels Alloyed With Cr And P, E V. Pereloma, M K. Miller Jan 2005

Atomic Observations Of Warm Rolled Low Carbon Steels Alloyed With Cr And P, E V. Pereloma, M K. Miller

Faculty of Engineering and Information Sciences - Papers: Part A

Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005


Role Of Cr And P Additions In The Development Of Microstructure And Texture In Annealed Low Carbon Steels, E V. Pereloma, I B. Timokhina, A I. Nosenkov, J J. Jonas Jan 2004

Role Of Cr And P Additions In The Development Of Microstructure And Texture In Annealed Low Carbon Steels, E V. Pereloma, I B. Timokhina, A I. Nosenkov, J J. Jonas

Faculty of Engineering and Information Sciences - Papers: Part A

The recrystallisation behaviour of four warm rolled steels was investigated during annealing. The extra-low carbon (ELC) steel displayed the highest rate of recrystallisation, the steels with additions of chromium and phosphorus (LC(Cr)), (LC(Cr,P)) recrystallised at intermediate rates, while the interstitial-free (IF) steel exhibited the lowest rate. The additions of Cr and Cr/P increased the fraction of g-fibre in the annealing textures compared to that present in the ELC steel; this effect was particularly pronounced up to 50 % recrystallisation. After the completion of recrystallisation, the steel textures were characterized by a dominant g-fibre in the IF steel, while in the …


Widmanstatten Ferrite Plate Formation In Low-Carbon Steels, Dominic Phelan, Rian Dippenaar Jan 2004

Widmanstatten Ferrite Plate Formation In Low-Carbon Steels, Dominic Phelan, Rian Dippenaar

Faculty of Engineering and Information Sciences - Papers: Part A

The mechanism by which Widmanstätten ferrite plates nucleate and grow in low-carbon steels has been studied. In-situ laser scanning confocal microscopy (LSCM) observations, optical microscopy, and electron backscattered diffraction (EBSD) techniques have been used to characterize the relationship between grain boundary allotriomorphs and Widmanstätten ferrite plates. The issue of where Widmanstätten ferrite plates nucleate is one of some debate, with theories including morphological instability and sympathetic nucleation. Evidence has been found that supports the theory of a sympathetic nucleation mechanism being responsible for the formation of Widmanstätten ferrite plates. The EBSD measurements have shown that low-angle misorientations of between 5 …


Delta-Ferrite Recovery Structures In Low-Carbon Steels, Rian Dippenaar, Dominic Phelan Jan 2003

Delta-Ferrite Recovery Structures In Low-Carbon Steels, Rian Dippenaar, Dominic Phelan

Faculty of Engineering and Information Sciences - Papers: Part A

The development of delta-ferrite recovery substructures in low-carbon steels has been observed in-situ utilizing laser scanning confocal microscopy (LSCM). Well-developed sub-boundaries with interfacial energies much smaller than that of delta-ferrite grain boundaries formed following transformation from austenite to delta-ferrite on heating. It is proposed that transformation stresses associated with the austenite to delta-ferrite phase transformation generate dislocations that subsequently recover into sub-boundaries by a process of polygonization. Experimental evidence in support of this proposal was found in a ferritic stainless steel. Thermal cycling through the high-temperature delta-ferrite/austenite/delta-ferrite phase transformation leads to the development of a well-defined recovery substructure, which, in …


Detection Of Carbon Monoxide Within The Magellanic Bridge, E Muller, L Staveley-Smith, William Zealey Jan 2003

Detection Of Carbon Monoxide Within The Magellanic Bridge, E Muller, L Staveley-Smith, William Zealey

Faculty of Engineering and Information Sciences - Papers: Part A

The Mopra 22-m and SEST 15-m telescopes have been used to detect and partially map a region of 12CO(1-0) line emission within the Magellanic Bridge, a region lying between the Large and Small Magellanic Clouds (LMC and SMC, respectively). The emission appears to be embedded in a cloud of neutral hydrogen, and is in the vicinity of an IRAS source. The CO emission region is found to have a 60 μm/100 μm flux density ratio typical for 12CO(1-0) detections within the SMC, although it has a significantly lower 12CO brightness and velocity width. These suggest that the …