Adelaide Microscopy publications

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Open Access
Application of coolants during tool-based machining – A review
(Elsevier BV, 2023) Zheng Yang, K.; Pramanik, A.; Basak, A.K.; Dong, Y.; Prakash, C.; Shankar, S.; Dixit, S.; Kumar, K.; Ivanovich Vatin, N.
Coolant is a substance that applied in a machining process for the efficient machining of materials. The application of coolants is based on the several factors including the types of machining process, workpiece material, cutting tool and cost. Coolant helps to dissipate the heat that can be generated during the machining operation, induce lubricating effects to decrease the friction caused by the interfaces of two surfaces, flush away chips and offer corrosion protection. With the right type of coolants used, the performance of machining applications and the attributes of workpieces can be remarkably enhanced. The objective of the study to provides a critical review on the mechanism of coolant penetration, functions, variety of coolants, cooling actions, effectiveness, applications, and the additives that alter the ability and properties of coolants. Furthermore, the critical review also addresses the new technology cryogenic machining that uses cryogenic gases as coolants instead of conventional coolants.
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Breeding system in a population of Trigonella balansae (Leguminosae)
(Oxford Univ Press, 2004) Nair, R.; Dundas, I.; Blesing, M.; Verlin, D.; Waterhouse, L.; Dowling, K.
Background and Aims Although some taxonomic studies in the genus Trigonella have been conducted, there has been no concerted effort to study the breeding system. This paper examines the floral structure and pollination system in a population of T. balansae, an annual pasture legume. Methods Floral morphology, hand and vector pollination, stigma receptivity, pollen tube growth, using scanning electron and fluorescence microscopy, were conducted. Key Results Measurements of floral structure from before to after anthesis indicates an inability for T. balansae to self-pollinate and a requirement for an external vector to effectively transfer pollen from the anthers onto the stigmas of this species. Seed set can be obtained by hand or honeybee manipulation of T. balansae flowers. Conclusions Trigonella balansae is a self-compatible species, but which requires vectors such as honeybees to bring about pollination.
Open Access
Cation Inversion in Slag Magnetite: Energy Loss Measurements of Fe-L₃ Edge Shift between Atom Columns
(Elsevier, 2023) Gezzaz, H.; Ciobanu, C.L.; Slattery, A.; Cook, N.J.; Ehrig, K.
Determination of cation disorder in inverse spinels like magnetite, Fe3O4, is of broad interest for applications in green technologies, storage devices, and nuclear waste management since cation distributions govern magnetic and electrical properties. Magnetite is a main component of slags produced by smelting of copper ores and contains potentially valuable trace elements. We address cation disorder as a factor controlling the behavior of these elements during atmospheric cooling from 1300 °C. To estimate cation disorder, we combine atomic-scale scanning transmission electron microscopy with electron energy loss spectroscopy. The inversion parameter (0.72) indicates minor partial ordering due to fast cooling from high temperature, resulting in skeletal textures. Trace element incorporation into magnetite, instead of exsolution of discrete nanoparticle phases is promoted. Our findings provide insights into the cooling behavior of spinels and facilitate robust thermodynamic modeling that addresses the stability of structures during cooling from melts. Findings carry implications for critical element recovery and prospects for transforming industrial waste into future resources.
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Cell death in LMA-affected wheat aleurone layers
(Royal Australian Chemical Institute, 2003) Mrva, K.; Blesing, M.; Mares, D.; Cereals 2003 (53rd : 2003 : Glenelg, South Australia); Black, C.; Panozzo, J.
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Coefficient of friction measured from nano- to macro-normal loads on plasma sprayed nanostructured cermet coatings
(ASM International, 2014) Basak, A.; Celis, J.; Vardavoulias, M.; Matteazzi, P.
Alumina dispersed FeCuAl-based nanostructured cermet coatings were deposited from nanostructured powders by atmospheric plasma spraying on low carbon steel substrates. Nanostructuring was retained in the deposited coatings which exhibit up to four distinctive phases as revealed by electron microscopy. In this study, the friction behavior of the distinctive phases at nano-normal load scale was investigated alongside their contribution to the overall friction behavior at macro-normal load scale. Friction behavior at nano-normal load scale was investigated by lateral force microscopy, whereas conventional tribometers were used for investigations at micro and macro-normal loads. It appeared that, the friction measured at nano-normal loads on individual phases is dictated by both composition and hardness of the corresponding phases, and thus influences the overall friction behavior of the coatings at macro-normal loads. Moreover, the coefficient of friction at macro-normal loads differs from the one at nano-normal loads, and deviates from Amonton’s friction law.
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Concentration of particulate platinum-group minerals during magma emplacement; a case study from the Merensky Reef, Bushveld Complex
(Oxford University Press, 2015) Hutchinson, D.; Foster, J.; Prichard, H.; Gilbert, S.
The petrology, mineralogy and geochemistry of a section of the Merensky Reef at Bafokeng Rasimone Platinum Mine (BRPM) are described. A model for the formation of platinum-group minerals (PGM), sulphide and chromitite is proposed that explains the stratigraphic relationships observed in the Merensky Reef, both at BRPM and at other locations in the Bushveld Complex. To achieve this it is necessary to understand platinum-group element (PGE) behaviour in naturally occurring mafic systems and for this reason comparisons are drawn from core TN207 through the Platreef at Tweefontein. The common link between the Platreef and Merensky Reef is the presence of unusually high concentrations of As, Sb, Bi and Te that promote the crystallisation of semi-metal bearing PGM from sulphide liquids. Under conditions of increasing semi-metal contamination, Pt is the first PGE to be extracted from a sulphide liquid followed by Rh, Ru, Os and Ir. While some Pd is released to form Pd-PGM much of it remains within the Ni-rich sulphide phase that crystallizes to form pentlandite. A critical aspect is the timing of their introduction into the magmatic system. For the Merensky magmas, contamination occurred predominantly within a staging chamber owing to wall-rock interaction with Transvaal sediments. This led to the formation of sulphide liquids that captured PGE and, ultimately, the crystallization of Pt- and Ru-PGM. The extreme enrichment in PGE and the high Pt/Pd ratios in the Merensky chromitites are attributed to density-driven concentration of PGM transported by magmas displaced from a staging chamber. Emplacement of these magmas into the Bushveld Complex resulted in thermo-mechanical erosion of the floor and deposition of chromites + sulphides + PGM. In places, these assemblages collected in sedimentary-like scour channels. In the Platreef, contamination occurred largely after magma emplacement owing to interaction with the local Transvaal sediments. As a result, mechanical separation of PGM did not occur and most PGM remain spatially associated with their original sulphide hosts.The Merensky Reef is a prime example of highly efficient PGE concentration resulting from mechanical processes, whereas the Platreef is a prime example of highly efficient PGE removal from sulphide liquids in response to extreme contamination by semi-metals.
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Construction of 2D lateral pseudoheterostructures by strain engineering
(IOP Publishing, 2017) Feng, H.; Zhuang, J.; Slattery, A.; Wang, L.; Xu, Z.; Xu, X.; Mitchell, D.; Zheng, T.; Li, S.; Higgins, M.; Ren, L.; Sun, Z.; Dou, S.; Du, Y.; Hao, W.
Two-dimensional (2D) lateral heterostructures host unconventional physical properties due to their controllable band-offset tuning and interfacial sensitive characteristic. The lattice mismatch results in the difficulties to construct the perfect atomic interface in such 2D lateral heterostructures, which in turn limits their desirable properties and performances in applications. In this work, strain-modulated 2D lateral pseudoheterogeneous structures are designed and realized in the single-component 2D BiOBr nanosheets by taking advantage of their strain-sensitive crystal and electronic structures. The pseudoheterogeneous interface without atomic mismatch can be feasibly modulated by local strain distribution, which exhibits similar local electronic band structure of corresponding heterostructures. Significant enhancement in charge separation at the pseudoheterostructure was demonstrated under visible light irradiation, which is given rise to the controllable electronic band alignment across the interface. The construction of the lateral pseudoheterostructure offers a feasible and promising way to build unprecedented 2D systems with exciting properties.
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Contribution of machining to the fatigue behaviour of metal matrix composites (MMCs) of varying reinforcement size
(Elsevier, 2017) Pramanik, A.; Islam, M.; Davies, I.; Boswell, B.; Dong, Y.; Basak, A.; Uddin, M.; Dixit, A.; Chattopadhyaya, S.
Abstract not available
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Cu-Ni-PGE fertility of the Yoko-Dovyren layered massif (northern Transbaikalia, Russia): thermodynamic modeling of sulfide compositions in low mineralized dunite based on quantitative sulfide mineralogy
(Springer-Verlag, 2016) Ariskin, A.; Kislov, E.; Danyushevsky, L.; Nikolaev, G.; Fiorentini, M.; Gilbert, S.; Goemann, K.; Malyshev, A.
The geology and major types of sulfide mineralization in the Yoko-Dovyren layered massif (northern Transbaikalia, Russia) are presented. This study focuses on the structure, mineralogy, and geochemistry of poorly mineralized plagiodunite and dunite in the lower part of the intrusion. Assuming these rocks contain key information on the timing of sulfide immiscibility in the original cumulate pile, we apply a novel approach which combines estimates of the average sulfide compositions in each particular rock with thermodynamic modeling of the geochemistry of the original sulfide liquid. To approach the goal, an updated sulfide version of the COMAGMAT-5 model was used. Results of simulations of sulfide immiscibility in initially S-undersaturated olivine cumulates demonstrate a strong effect of the decreasing fraction of the silicate melt, due to crystallization of silicate and oxide minerals, on the composition of the intercumulus sulfide liquid. Comparison of the observed and modeled sulfide compositions indicates that the proposed modeling reproduces well the average concentrations of Cu, Cd, Ag, and Pd in natural sulfides. This suggests the sulfide control on the distribution of these elements in the rocks. Conversely, data for Pt and Au suggest that a significant portion of these elements could present in a native form, thus depleting the intercumulus sulfide melt at an early stage of crystallization.
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Deformation of electrodeposited gradient Co/Sn multilayered coatings under micro-pillar compression
(Elsevier, 2018) Kurdi, A.; Basak, A.
Compositionally modulated multilayer (CMM) Co-Sn coating were successfully deposited with the help of electrodeposition on copper substrate. The coating microstructure was homogeneous, nanostructured in nature with smooth and distinct interfaces as confirmed by SEM and TEM investigation. In this study, micro-mechanical properties of such CMM Co-Sn coatings has been investigated by means of micro-pillar compression. Micro-mechanical properties of electrodeposited monolithic sole Co and sole Sn coatings was also investigated for comparison purpose. CMM Co-Sn coating shows high flow strength of about 330 MPa, which is about 1.2 and 5 times higher than that of sole Co and sole Sn coating, respectively. Such enhanced mechanical properties are the result of intermixing of several thin Co-Sn layers to form a single broad layer to accommodate deformation of material and to minimize system’s energy as evident by detail transmission electron microscopy investigation on deformed micro-pillars.
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Density changes around phosphorus granules and fluid bands in a calcareous soil
(Soil Sci Soc Amer, 2006) Hettiarachchi, G.; Lombi, E.; McLaughlin, M.; Chittleborough, D.; Self, P.
We employed x-ray computed microtomography (X-ray CT) to observe differences in moisture around fertilizer P granules (monoammonium phosphate, MAP) versus injection zones of fluid P fertilizer (technical grade monoammonium phosphate, TG MAP) in a calcareous soil over time. X-ray CT allows nondestructive visualization of small columns containing soils and fertilizers. We were able to visualize the increase in density around the highly hygroscopic fertilizer granule over time. It appeared that both water flow toward the granule and precipitation of P could be responsible for the development of about 1 mm thick high density zone immediately adjacent to the granule. The mass flow of water toward the granule may have slowed or restricted the diffusion of fertilizer P from the granule, thus increasing the chances for P fixation through precipitation reactions. Also, the granule became less dense with time indicating the progress of granule dissolution. In contrast, injection of fluid fertilizer (TG-MAP) in soil did not result in moisture changes over time as evidenced by a lack of X-ray CT detectable density differences in the soil column. These data support previous findings that, when P is supplied in granular form, P diffusion and isotopic lability in calcareous soils are reduced compared with equivalent liquid fertilizer formulations, probably due to precipitation reactions induced by osmotically induced flow of soil moisture into the fertilizer granule.
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Developments of rubber material wear in conveyer belt system
(Elsevier, 2017) Hakami, F.; Pramanik, A.; Ridgway, N.; Basak, A.
Regular degradation of rubbers contribute frequent maintenance of conveyer belt system. This paper investigates wear rate and mechanisms of rubber and associated influential parameters based on the information available in literature. Abrasion, fatigue and roll formation are dominate wear mechanisms that are influenced by load, sliding velocity, hardness and friction. Correlations among influential parameters and their effect on rubber wear was established in details. Archad's equation does not work for rubber wear but researchers have proposed equations similar to that. Adhesion wear forms roll in the smooth surface when tear strength of rubber is low. Wear caused by adhesion is abrasion when surface texture is harsh. Hysteresis enhances fatigue wear if the substrate asperities are round or blunt.
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Effect of nanostructuring and Al alloying on friction and wear behaviour of thermal sprayed WC-Co coatings
(Elsevier, 2012) Basak, A.; Celis, J.; Vardavoulias, M.; Matteazzi, P.
Abstract not available
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Effects of chemical functional groups on the polymer adsorption behavior onto titania pigment particles
(Academic Press Inc Elsevier Science, 2004) Farrokhpay, Saeed; Morris, G.; Fornasiero, Daniel; Self, Peter Geoffrey; Adelaide Microscopy
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Electrical discharge machining of 6061 aluminium alloy
(Elsevier, 2015) Pramanik, A.; Basak, A.; Islam, M.; Littlefair, G.
The wire electrical discharge machining (EDM) of 6061 aluminium alloy in terms of material removal rate, kerf/slit width, surface finish and wear of electrode wire for different pulse on time and wire tension was studied. Eight experiments were carried out in a wire EDM machine by varying pulse on time and wire tension. It is found that the material removal rate increases with the increase of pulse on time though the wire tension does not affect the material removal rate. It seems that the higher wire tension facilitates steady machining process, which generates low wear in wire electrode and better surface finish. The surface roughness does not change notably with the variation of pulse on time. The appearance of the machined surfaces is very similar under all the machining conditions. The machined surface contains solidified molten material, splash of materials and blisters. The increase of the pulse on time increases the wear of wire electrode due to the increase of heat input. The wear of wire electrode generates tapered slot which has higher kerf width at top side than that at bottom side. The higher electrode wear introduces higher taper.
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Evaluation of high power ultrasound porous cleaning efficacy in American oak wine barrels using X-ray tomography
(Elsevier BV, 2011) Porter, G.; Lewis, A.; Barnes, M.; Williams, R.
This study presents a novel cleaning application which investigates the ability of high power ultrasound (HPU) to remove crystalline potassium hydrogen tartrate sediment from the porous structure of American oak wine barrels. Tartrate deposits within stave samples were imaged by X-ray tomography. Volumetric reconstruction software enabled tartrate volumes to be quantified after successive treatments at varied solvent temperatures by re-imaging samples and modelling obtained tomographic projections. The removal of microscopic tartrate crystals from stave surfaces by HPU was also investigated. It was demonstrated that HPU can significantly remove tartrate deposits from the first two millimetres of oak surfaces however such ability at depth 2-8 mm was not reproducible. An average of 89% total tartrate volume was removed from the surface layer in the first treatment but was further increased to 98% by increasing solvent temperature and irradiation time. A highly significant removal of stave surface tartrate crystals with this cleaning technique was also demonstrated at temperatures studied. Industrial Relevance: Fouling of the interior surface and porous membranes of wine barrels is a significant problem encountered by every wine maker. This problem occurs in white and red wine production by precipitated tartrate crystallisation which forms a robust scale inhibiting oak compound extraction by wine, additionally harbouring spoilage microorganisms and contaminants. Tartrate scale is typically removed by spray techniques, but often with less than optimal results. Ultrasonic cleaning is a well established practice in many industries; this industrial scaled study demonstrates a high power ultrasonic (4 kW/20 kHz) application in the effective and efficient removal of tartrate sediment from the surface of staves, and to a depth of two millimetres, with a relatively short treatment time (12 min) at mild temperatures (40-60 °C). Such outcomes are expected to benefit the wine industry, consumers and environment by increased barrel functionality and less frequent replacement, an improvement in oak compound extraction rate and concentration in wine, increased product quality, as well as the minimisation of cleaning water consumption and excessive use of preservatives. © 2011 Elsevier Ltd. All rights reserved.
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Fractionation of sulphur relative to iron during laser ablation-ICP-MS analyses of sulphide minerals: implications for quantification
(Royal Society of Chemistry, 2014) Gilbert, S.; Danyushevsky, L.; Goemann, K.; Death, D.
In this study we investigate the effect that the mineral composition has on the quantification of sulphur by Laser Ablation ICP-MS (LA-ICP-MS) between a range of sulphide minerals: pyrite, pyrrhotite, bornite, chalcopyrite, sphalerite, pentlandite and tetrahedrite. The amount of S fractionation, relative to Fe, was compared between three different nano-second pulse width laser ablation systems: a 213 nm Nd:YAG, a 193 nm Nd:YAG and a 193 nm excimer. Significant matrix effects were seen for some minerals. With the 213 nm Nd:YAG laser, the yield (sensitivity per µg g⁻¹) of S relative to Fe is up to 50% higher for tetrahedrite and approximately 30% higher for bornite and chalcopyrite when compared to the yields of pyrite, whereas no fractionation was seen between Cu and Fe. For analyses on a fixed position on the sample, significant down-hole fractionation (DHF) occurred where S/Fe ratios increased during an analysis. The rate of DHF is also mineral specific, enhancing the need for matrix matched standards for accurate S analysis. The ablation properties of the minerals were also investigated by characterising the shape of the ablation craters and the composition and morphology of the deposited aerosol material around the ablation site using a field emission scanning electron microscope (FE-SEM). At fluences below 3.5 J cm⁻², pyrite is ablated efficiently by all laser systems with minimal melting around the ablation site, producing steep sided ablation craters. However, some melting occurs in and around the craters for most other sulphide minerals. The amount of melting is mineral specific and primarily dependent on its physical properties (e.g., bond strength and melting point). The greater the extent of melting, the more S fractionation occurs, consistent with the higher volatility of S relative to Fe.
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Fracture and fatigue life of Al-based MMCs machined at different conditions
(Elsevier, 2018) Pramanik, A.; Basak, A.
This study investigates fracture and fatigue performance of metal matric composites (MMCs) without any reinforcement and, 0.7 and 13 μm particle (10 vol%) reinforced which were machined at different feeds and speeds. Fractured surface as well as fatigue generated cracks were investigated in details. The effect of interactions among input machining parameters with their variations on fatigue life has also been analysed. It was found that fatigue cracks don’t follow machining traces. Moreover, the cracks are almost straight and sharp when reinforcing particles are smaller but change the course, and surface along the crake is highly damaged when the reinforced particles are bigger. The appearance of fractured surfaces of the samples are very similar regardless of particles size and machining conditions. Though compressive residual stress is generated on the machined MMC surfaces, fatigue life of MMCs are much shorter than that of corresponding matrix material due to the fracture and detachment of reinforcing particles from matrix. Fatigue life has an initial decreasing trend with the rise of feed-rate and then it increases significantly with further increase of feed-rate in the absence of particles machine at low speed. However, fatigue life remains almost constant with the increase of feed-rate for larger particle reinforced MMC machined at high speed. With the increase of speed, opposite trends on fatigue life were noticed for MMCs and matrix material when machined at low and high feeds, respectively. The larger reinforced particles reduces the fatigue life of machined specimens at every interacting combinations of parameters.
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Gun shot residue analysis and distinguishing the formation of GSR from environmental particles
(Springer-Verlag, 2009) Sarvas, I.; Kobus, H.; Green, L.; Kotula, P.; Wuhrer, R.; Adelaide Microscopy
Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009
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Inclusion-localised crystal-plasticity, dynamic porosity, and fast-diffusion pathway generation in zircon
(Pergamon-Elsevier Science Ltd, 2012) Timms, N.; Reddy, S.; John, D.; Green, L.; Muhling, J.; Adelaide Microscopy
A population of oscillatory zoned, igneous zircon grains in a Javanese andesite contains fluid and mineral inclusions (up to 10μm across) trapped during zircon growth. Orientation contrast imaging and orientation mapping by electron backscatter diffraction reveal that crystal-plastic deformation overprints growth zoning and has localized around 1-10μm pores and inclusions. Cumulative crystallographic misorientation of up to 25° around pores and inclusions in zircon is predominantly accommodated by low-angle (<5°) orientation boundaries, with few free dislocations in subgrain interiors. Low-angle boundaries are curved, with multiple orientation segments at the sub-micrometer scale. Misorientation axes associated with the most common boundaries align with the zircon c-axis and are consistent with dislocation creep dominated by <100>(010) slip. A distinctly different population of sub-micron pores is present along subgrain boundaries and their triple junctions. These are interpreted to have formed as a geometric consequence of dislocation interaction during crystal-plasticity. Dislocation creep microstructures are spatially related to differences in cathodoluminescence spectra that indicate variations in the abundance of CL-active rare earth elements. The extent of the modification suggests deformation-related fast-pathway diffusion distances that are over five orders of magnitude greater than expected for volume diffusion. This enhanced diffusion is interpreted to represent a combination of fast-diffusion pathways associated with creep cavitation, dislocations and along low-angle boundaries. These new data indicate that ductile deformation localised around inclusions can provide fast pathways for geochemical exchange. These pathways may provide links to the zircon grain boundary, thus negating the widely held assumption that inclusions in fracture-free zircon are geochemically armoured once they are physically enclosed. © 2011.

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