title: Effect of combined lean additions of isomorphous and eutectoid beta stabilisers on the properties of titanium

authors: Bolzoni, Leandro

abstract: Reduction of the manufacturing cost of titanium and the development of new alloys are crucial to effectively harvest the benefits derived by the use of titanium in industrial applications. Therefore, we considered the creation of new Ti-2X-2Z alloys via the combined lean additions of isomorphous (i.e. Nb) and eutectoid (i.e. Cu, Mn, and Fe) beta stabilisers, and systematically analysed their effect on the manufacturability and mechanical response of titanium produced via powder metallurgy. It is found that the addition of the alloying elements reduces the compressibility of the powder blend but enhances the densification. The microstructure of titanium is transformed into a Widmanst€atten structure composed of a grain boundaries and aþb lamellae where the stronger the beta stabilisers the more refined the microstructural features, and no intermetallic phases are precipitated despite the use of eutectoid stabilisers. Consequently, the combined addition of isomorphous and eutectoid beta stabilisers has a significant effect on the mechanical response with the material becoming stronger, harder and less tough with the increment of the potency of the added beta stabilisers; however, the Ti-2X-2Z alloys share similar strengthening mechanisms. A more accurate theoretical equation for developing titanium alloys through the molybdenum equivalent parameter should be developed

text: Effect of combined lean additions of isomorphous and eutectoid beta stabilisers on the properties of titanium Reduction of the manufacturing cost of titanium and the development of new alloys are crucial to effectively harvest the benefits derived by the use of titanium in industrial applications. Therefore, we considered the creation of new Ti-2X-2Z alloys via the combined lean additions of isomorphous (i.e. Nb) and eutectoid (i.e. Cu, Mn, and Fe) beta stabilisers, and systematically analysed their effect on the manufacturability and mechanical response of titanium produced via powder metallurgy. It is found that the addition of the alloying elements reduces the compressibility of the powder blend but enhances the densification. The microstructure of titanium is transformed into a Widmanst€atten structure composed of a grain boundaries and aþb lamellae where the stronger the beta stabilisers the more refined the microstructural features, and no intermetallic phases are precipitated despite the use of eutectoid stabilisers. Consequently, the combined addition of isomorphous and eutectoid beta stabilisers has a significant effect on the mechanical response with the material becoming stronger, harder and less tough with the increment of the potency of the added beta stabilisers; however, the Ti-2X-2Z alloys share similar strengthening mechanisms. A more accurate theoretical equation for developing titanium alloys through the molybdenum equivalent parameter should be developed

year: 2022-11

title: A high resolution full-field range imaging system for robotic devices

authors: Carnegie, Dale A.

subjects: robot sensing

abstract: There has been considerable effort by many researchers to develop a high resolution full-field range imaging system. Traditionally these systems rely on a homodyne technique that modulates the illumination source and shutter speed at some high frequency. These systems tend to suffer from the need to be calibrated to account for changing ambient light conditions and generally cannot provide better than single centimeter range resolution, and even then over a range of only a few meters. We present a system, tested to proof-of-concept stage that is being developed for use on a range of mobile robots. The system has the potential for real-time, sub millimeter range resolution, with minimal power and space requirements.

text: A high resolution full-field range imaging system for robotic devices There has been considerable effort by many researchers to develop a high resolution full-field range imaging system. Traditionally these systems rely on a homodyne technique that modulates the illumination source and shutter speed at some high frequency. These systems tend to suffer from the need to be calibrated to account for changing ambient light conditions and generally cannot provide better than single centimeter range resolution, and even then over a range of only a few meters. We present a system, tested to proof-of-concept stage that is being developed for use on a range of mobile robots. The system has the potential for real-time, sub millimeter range resolution, with minimal power and space requirements.

year: 2005

title: Exploring the constitution of environment education as situated, critical processes of learning and change: A collaborative synthesis across diverse regional contexts

authors: Eames, Chris W.

subjects: Critical approaches

abstract: This article offers a set of unique vignettes or stories that attempt to illustrate examples of critical approaches to environmental education (EE) in diverse contexts. It draws from the experiences of five environmental educators in four different regions of the world. We detail the history of the emergence of critical consciousness in education in Brazil, and its application in a Brazilian region, then move to examples of critical educational responses to oppression in New Zealand and Zimbabwe, before closing with a critical examination of innovative teaching and research in Europe. Through this breadth of endeavour, we identify commonalities across these contexts such as the importance of participatory action and research to examine peopleenvironment relations, particularly as constituted by indigenous peoples, and to interpret realities in ways that empower through learning-led social-ecological change. We argue that this critical approach can foster emancipation through individual and collective learning in EE processes within very different contexts.

text: Exploring the constitution of environment education as situated, critical processes of learning and change: A collaborative synthesis across diverse regional contexts This article offers a set of unique vignettes or stories that attempt to illustrate examples of critical approaches to environmental education (EE) in diverse contexts. It draws from the experiences of five environmental educators in four different regions of the world. We detail the history of the emergence of critical consciousness in education in Brazil, and its application in a Brazilian region, then move to examples of critical educational responses to oppression in New Zealand and Zimbabwe, before closing with a critical examination of innovative teaching and research in Europe. Through this breadth of endeavour, we identify commonalities across these contexts such as the importance of participatory action and research to examine peopleenvironment relations, particularly as constituted by indigenous peoples, and to interpret realities in ways that empower through learning-led social-ecological change. We argue that this critical approach can foster emancipation through individual and collective learning in EE processes within very different contexts.

year: 2018