The formation of ultrafine grained steel microstructures through thermomechanical processing.

The formation of ultrafine grained steels is an area of intense research around the World. There are a number of methods to produce grain sizes of approximately 1 µm, ranging from extreme thermal and deformation cycles to more typical thermomechanical processes. This paper reviews the status of the production of ultrafine grained steels through relatively simple thermomechanical processing. It is shown that this requires deformation within the Ae3 to Ar3 temperature range for a given alloy. The formation of ultrafine ferrite involves a dynamic transformation of a significant volume fraction of the austenite to ferrite. This dynamic strain induced transformation arises from the introduction of additional intragranular nucleation sites. It is possible that the deformation also hinders the growth or coarsening of the ferrite and may also lead to dynamic recrystallization of the ferrite. The most likely commercial exploitation of ultrafine ferrite would appear to rely on the formation of a critical volume fraction of dynamic strain induced ferrite followed by controlled cooling to ensure this is maintained to room temperature and to also form other secondary phases, such as martensite, bainite and/or retained austenite to improve the formability.

Development, implementation, and evaluation of a continence education package in acute and subacute care settings

OBJECTIVE: The objective of the study was to trial and evaluate the effect that a discharge Continence Education Package (CEP) had on patients' continence awareness and management preferences.
DESIGN: An exploratory descriptive design was used.
SETTINGS AND SUBJECTS: A total of 631 participants were included in the study: 352 females (55.8%) and 279 males (44.2%) from 4 rural and regional settings in Victoria, Australia.
INSTRUMENTS AND METHODS: A specifically designed questionnaire was used to assess participants' knowledge of incontinence and its management and also to investigate their treatment preferences and intentions if they experienced this type of problem. Data were collected at 2 time periods. Specifically, patients were interviewed before discharge from acute and subacute settings identified as Time 1 (T1). Then the participants were given the CEP and asked to complete a similar questionnaire.
RESULTS: The findings revealed that fewer than 25% of participants had received information on continence before the study being conducted, yet the majority had indicated that they had experienced continence symptoms. The majority of participants found the CEP easy to understand (98.2%) and helpful (95.3%). Most participants said it provided them with information about types of actions to take and/or treatment options for incontinence problems. It also raised their awareness of the signs and symptoms associated with incontinence and provided them with a useful self-administered gauge with which to assess their continence status.
CONCLUSIONS: These findings suggest that the CEP may be a useful educational tool for use in the general population.

Formation of a W-25%Cu nanocomposite during high pressure torsion

A coarse-grained W–25%Cu composite is subjected to high pressure torsion (HPT) at room temperature, 200 °C, and 400 °C, to different very large strains. The evolution of microstructure with increasing strain is investigated. It is shown that the HPT causes a strong refinement of W particles. No significant influence of the deformation temperature on the microstructure is revealed at small strains (64). A strong effect of the HPT temperature on the microstructure is found at larger strains (>64). It is demonstrated that the HPT can be successfully used to fabricate a W–25%Cu nanocomposite.

The formation of ultrafine ferrite in low C steels through thermomechanical processing

Ultrafine ferrite can be formed in steels through relatively simple thermomechanical processes. The ferrite nucleates intragranularly within the austenite grain on deformation features, which are favoured by heavy shear and large effective strains. It is also possible to produce ultrafine microstructures under multipass deformation conditions, although these may be due to dynamic recovery rather than strain induced transformation.

Back from the brink: reclaiming `quality` in the pursuit of a transformative education agenda

Discussions about ‘quality’ and ‘quality assurance’ abound in contemporary Australian universities. Since 1992, the Australian federal government has ‘promoted’ and/or mandated the use of particular quality assurance mechanisms within higher education and in 2001 The Australian University Quality Agency began to conduct the first of a series of ‘audits’ aimed at determining how well particular institutions meet standards and achieve
outcomes overseen, at least indirectly, by government agencies.

Effectiveness of fire safety education in primary school children

Young children have been identified as a high-risk group in relation to fire-related deaths because of their limited ability to understand the intinsic dangers of fire, to foresee the consequences of playing with fire, or to manage a fire if it were to become out of control.  Children are also not equipped to respond in a meaningful way in the event of a fire.  It is therefore essential that fire safety education be imparted to children in an effective manner so as to equip them to deal with a fire efficiently.  The objective of the present study was to evaluate the 'Fire Ed' program conducted by the Melbourne Metropolitan Fire Brigade for primary school children to determine whether exposure to the curriculum will influence children's knowledge of fire safety behaviours.  Although the program has numerous positive features, its overall effectivenedd has not been evaluated.  It was hypothesised that: a) children will not be aware of essential fire safety information prior to attending the 'Fire Ed' program, and b) children will display a significant gain in fire safety knowledge after participation in the program.  Sixty children from six primary schools participated in the study and they were tested on their level of fire safety knowledge prior to and after partcipation in the 'Fire Ed' program.  Results show that the children's knowledge of fire safety procedures improved significantly after participation in the program when tested after three weeks, however, when their knowledge was examined after five weeks, a significant decline was seen.  The findings show that regular evaluations of fire safety programs are required and that they could be improved by considering the different stages of cognitive development in children.

Formation of ultra-fine ferrite in hot rolled strip: potential mechanisms for grain refinement

A novel single-pass hot strip rolling process has been developed in which ultra-fine (<2 μm) ferrite grains form at the surface of hot rolled strip in two low carbon steels with average austenite grain sizes above 200 μm. Two experiments were performed on strip that had been re-heated to 1250°C for 300 s and air-cooled to the rolling temperatures. The first involved hot rolling a sample of 0.09 wt.%C&ndash;1.68Mn&ndash;0.22Si&ndash;0.27Mo steel (steel A) at 800°C, which was just above the Ar3 of this sample, while the second involved hot rolling a sample of 0.11C&ndash;1.68Mn&ndash;0.22Si steel (steel B) at 675°C, which is just below the Ar3 temperature of the sample. After air cooling, the surface regions of strip of both steel A and B consisted of ultra-fine ferrite grains which had formed within the large austenite grains, while the central regions consisted of a bainitic microstructure. In the case of steel B, a network of allotriomorphic ferrite delineated the prior-austenite grain boundaries throughout the strip cross-section. Based on results from optical microscopy and scanning/transmission electron microscopy, as well as bulk X-ray texture analysis and microtextural analysis using Electron Back-Scattered Diffraction (EBSD), it is shown that the ultra-fine ferrite most likely forms by a process of rapid intragranular nucleation during, or immediately after, deformation. This process of inducing intragranular nucleation of ferrite by deformation is referred to as strain-induced transformation.

The effect of multiple deformations on the formation of ultrafine grained steels

A C-Mn-Nb-Ti steel was deformed by hot torsion to study ultrafine ferrite formation through dynamic strain-induced transformation (DSIT) in conjunction with air cooling. A systematic study was carried out first to evaluate the effect of deformation temperature and prior austenite grain size on the critical strain for ultrafine ferrite formation (&epsilon; C,UFF) through single-pass deformation. Then, multiple deformations in the nonrecrystallization region were used to study the effect of thermomechanical parameters (i.e., strain, deformation temperature, etc.) on &epsilon; C,UFF. The multiple deformations in the nonrecrystallization region significantly reduced &epsilon; C,UFF, although the total equivalent strain for a given thermomechanical condition was higher than that required in single-pass deformation. The current study on a Ni-30Fe austenitic model alloy revealed that laminar microband structures were the key intragranular defects in the austenite for nucleation of ferrite during the hot torsion test. The microbands were refined and overall misorientation angle distribution increased with a decrease in the deformation temperature for a given thermomechanical processing condition. For nonisothermal multipass deformation, there was some contribution to the formation of high-angle microband boundaries from strains at higher temperature, although the strains were not completely additive.

The formation of ultrafine ferrite through static transformation in low carbon steels

A novel approach was used to produce an ultrafine grain structure in low carbon steels with a wide range of hardenability. This included warm deformation of supercooled austenite followed by reheating in the austenite region and cooling (RHA). The ultrafine ferrite structure was independent of steel composition. However, the mechanism of ferrite refinement hanged with the steel quench hardenability. In a relatively low hardenable steel, the ultrafine structure was produced through dynamic strain-induced transformation, whereas the ferrite refinement was formed by static transformation in steels with high quench hardenability. The use of a model Ni&ndash;30Fe austenitic alloy revealed that the deformation temperature has a strong effect on the nature of the intragranular defects. There was a transition temperature below which the cell dislocation structure changed to laminar microbands. It appears that the extreme refinement of ferrite is due to the formation of extensive high angle intragranular defects at these low deformation temperatures that then act as sites for static transformation.

Encouraging small firm up-take of SCM using education: a future research agenda

The success of supply chain management (SCM) practices often depends on small firms in the supply chain adopting these practices, yet they are often reluctant to do so. The existing literature mostly explores SCM adoption barriers rather than approaches to encourage adoption. This paper argues that an educational perspective has promise, and proposes a research agenda which should guide future studies by all researchers studying small firm SCM up-take. The agenda encompasses the diversity of small firms, the major educational players, appropriate types of education approaches and the theoretical framework to underpin this research. The paper then gives an example of how this research agenda can be applied to a specific research project which will explore the impact of the Supply Chain Knowledge Centre (SCKC), a state of the art SCM education facility developed by GS1 Australia, on small firm SCM up-take.

Effect of process variables on formation of dynamic strain induced ultrafine ferrite during hot torsion testing

Ultrafine grain sizes were produced using hot torsion testing of a 0.11C-1.68Mn-0.20Si (wt-%) steel, with ultrafine ferrite (<1 µm) nucleating intragranularly during testing by dynamic strain induced transformation. A systematic study was made of the effect of isothermal deformation temperature, strain level, strain rate, and accelerated cooling during deformation on the formation of ultrafine ferrite by this process. Decreasing the isothermal testing temperature below the Ae<sub>3sub> temperature led to a greater driving force for ferrite nucleation and thus more extensive nucleation during testing; the formation of Widmanstätten ferrite prior to, or early during, deformation imposed a lower temperature limit. Increasing the strain above that where ferrite first began 0.8 at 675C and a strain rate of 3 s¯<sup>1sup> increased the intragranular nucleation of ferrite. Strain rate appeared to have little effect on the amount of ferrite formed. However, slower strain rates led to extensive polygonisation of the ferrite formed because more time was available for ferrite recovery. Accelerated cooling during deformation followed by air cooling to room temperature led to a uniform microstructure consisting of very fine ferrite grains and fine spherical carbides located in the grain boundaries regions. Air cooling after isothermal testing led to carbide bands and a larger ferrite grain size.

Pennsylvanian (Carboniferous) brachiopods from the Itaituba Formation of the Amazon Basin, Brazil

A new brachiopod fauna is described from the lower Itaituba Formation at the Caima Quarry 2 section in the Itaituba area, Amazon Basin, Brazil. The Amazonoproductus amazonensis-Anthracospirifer oliveirai Assemblage is proposed for this fauna, which is considered early Pennsylvanian (Morrowan) as constrained by associated conodont and fusulinacean faunas. Nine brachiopod taxa are described herein, including Amazonoproductus amazonensis gen. et sp. nov., and Buxtonioides itaitubensis sp. nov. and Linoproductus caima sp. nov. The new tribe Marginovatini of the Linoproductoidea (the Productida) is also proposed.