N.R. Chapman, B. Micklethwaite and G.A. Pickup
Summary A study has been made of the oxidation of a range of chromized and chrome‐aluminized alloys in flowing air and flue gas atmospheres in the temperature range 500°C—900°C…
Abstract
Summary A study has been made of the oxidation of a range of chromized and chrome‐aluminized alloys in flowing air and flue gas atmospheres in the temperature range 500°C—900°C. Oxidation data for the full range of alloys are given but only chromized and chrome‐aluminized mild steel are covered in depth.
Toni Edgell and Hannah Lorimer
Research indicates the challenges indeterminate sentenced prisoners (ISPs) face within open prison may have a potentially devastating impact on rehabilitation and prison sentence…
Abstract
Purpose
Research indicates the challenges indeterminate sentenced prisoners (ISPs) face within open prison may have a potentially devastating impact on rehabilitation and prison sentence progression. The authors conducted a study in an English open prison to explore whether the closed prison environment within England and Wales is sufficiently preparing ISPs for the transition to open conditions. There is currently a gap in existing research concerning this issue, which this paper aims to narrow for the purpose of informing good practice and improving sentence progression and rehabilitation outcomes within His Majesty’s Prison and Probation Service.
Design/methodology/approach
Qualitative and exploratory. Reflexive thematic analysis was conducted to identify themes (Braun and Clarke, 2019).
Findings
Findings indicated the need for policy in closed prisons to better prepare ISPs for open prison and the need for policy in open prisons to better support ISPs during the liminal phase.
Practical implications
Findings aimed to inform consideration for improvements to enhance preparation for, and transition to, open conditions. A 17-month follow-up after dissemination of the research found evidence for the practical application of the findings at a local level within HMPPS and potential for wider applications linking to strategy and ISP initiatives.
Originality/value
If applied more widely across HMPPS in both closed and open prisons, the research findings have the potential to improve sentence progression and rehabilitation outcomes for ISPs.
DISCUSSION The chromium coating thicknesses used in this work were comparable to those used commercially, being between 70 and 170 micrometres approximately. Even after oxidation…
Abstract
DISCUSSION The chromium coating thicknesses used in this work were comparable to those used commercially, being between 70 and 170 micrometres approximately. Even after oxidation for the temperatures and times stated the chromium concentrations at the metal‐oxide interface were between 20% and 60%. These concentrations fell steadily to approximately 13% over the approximate depth stated above before reducing sharply to zero at what was the ferrite‐austenite transformation boundary during the coating process. This is contrary to the structure observed in aluminized stainless steels where a complex structure is produced due to the existence of intermetallic phases. Hence during all the oxidation experiments performed the chromium level of the surface offered for oxidation was never below 13% and complete oxidative breakdown therefore did not occur, excluding spalling effects. Many workers have shown that the oxidation rate of iron‐chromium alloys initially drops sharply with increasing chromium but eventually reaches a minimum of about 20% chromium and then rises for more chromium rich alloys. From the graph of oxidation rate in pure oxygen against chromium content given by Mortimer et al., from 13% chromium to 100% chromium the oxidation rate increases by approximately 6 × 10−9 g.cm−2 sec.−1 It is reasonable to assume that for a diffusion coating the oxidation behaviour will be markedly affected by the composition at its outer surface layer and much less by the composition gradient. If oxidation was continued for sufficiently long periods the latter could affect the general availability of chromium ions for the oxidation process. Over the first 5?m the average chromium levels were between 63% and 20% for the chromised and chrome‐aluminized respectively. From the figures given by Mortimer et al the oxidation rate of the 63% chromium coating would be expected to be 0.5 × 10−9 g.cm−2 sec−1 greater than the 20% chromium coating on the chrome‐aluminized specimens at 600°C, on the basis of the chromium content alone. The results obtained here vary in this manner, hence it is reasonable to conclude that the general oxidation behaviour of the coatings will be very similar to that of pure iron‐chromium alloys containing the same chromium content as in the outer few micrometres of the respective coatings. Even though the true surface area is greater with diffusion treated specimens their oxidation rates are lower that for the corresponding pure alloys.
In connection with the launching as a new British Standard of the revised “Code of Practice for Protective Coating of Iron and Steel Structures Against Corrosion”, the Association…
Abstract
In connection with the launching as a new British Standard of the revised “Code of Practice for Protective Coating of Iron and Steel Structures Against Corrosion”, the Association of Metal Sprayers published a “Plain Guide to BS 5493: 1977”. The “Plain Guide” introduces the new Code of Practice to owners and managers of structures, consulting engineers, designers, architects and all specifiers of protective systems for steel; it enables them to take advantage of the wealth of information which has been assembled in BS 5493 and which initially might appear to the engineer not intimately involved in corrosion protection. The Guide, main details of which are published below, charts the way through the Standard and should enable everybody more readily to make full use of the information and advice contained within BS 5493. Full copies of “Plain Guide to BS 5493” can be obtained from the Association of Metal Sprayers, Chamber of Commerce, Ward Street, Walsall WS1 2AG, at a cost of 40p each including postage.
A.N. Mukherji and P. Prabhakaram
In the present work, the authors carried out siliconizing, chromizing, aluminizing and chrome‐aluminizing of mild steel in a pack cementation process with a view to evaluate the…
Abstract
In the present work, the authors carried out siliconizing, chromizing, aluminizing and chrome‐aluminizing of mild steel in a pack cementation process with a view to evaluate the optimum experimental conditions to obtain satisfactory coatings which possess high resistance to oxidation. It is visualised to adopt some of the experimental conditions in later experiments where diffusion coating treatments are carried out using pastes containing the various diffusion elements. Some of the findings of the authors in siliconizing, chromizing, aluminizing and chrome‐aluminizing of mild steel in pack process are reported. It was observed that there is excess grain growth during siliconizing by the pack process and the coatings are porous and lack good oxidation resistance compared to coatings in the gas phase carried out by other workers. Chromized, aluminized and chrome‐aluminized samples are superior to 18/8 stainless steel and even Inconel in their oxidation resistance. Chromizing followed by aluminizing makes the coating layer less brittle as observed by the micro hardness measurements across the layer and hence chrome‐aluminizing will improve the spoiling resistance of the coatings.
Gihan Anuradha Tennakoon, Raufdeen Rameezdeen and Nicholas Chileshe
Timber waste from construction is downcycled into non-structural products, incinerated for energy generation or disposed of in landfills. Existing literature highlights that the…
Abstract
Purpose
Timber waste from construction is downcycled into non-structural products, incinerated for energy generation or disposed of in landfills. Existing literature highlights that the use of reprocessed timber for structural purposes is limited. Therefore, this study aims to focus on identifying factors limiting reprocessed structural timber (RST) uptake amongst construction professionals in Australia.
Design/methodology/approach
Current literature shows that the use of reprocessed materials (RMs) depends on user-specific personal factors and broader contextual factors. Therefore, data collection and analysis were based on the attitude-behaviour-context (ABC) theory, which affirms this relationship between personal and contextual factors in determining pro-environmental behaviours (PEBs). A qualitative research approach was adopted, considering limitations with industry expertise and the need for developing an in-depth understanding of limiting factors. Twenty semi-structured interviews were conducted amongst construction professionals experienced in using reprocessed materials, while the thematic analysis technique was used to analyse interview findings.
Findings
Personal factors that limit the uptake of RST include negative cost and quality perceptions, risk appetite, the tendency to maintain the status-quo, limited decision-making capability and lack of skills and expertise, while contextual factors include higher prices, poor and uncertain quality, limitations with information availability, under-developed supply and drawbacks in the regulatory environment.
Originality/value
The current study is amongst the first to explore the uptake of reprocessed timber for structural uses in Australia. The findings can be utilised to create a stronger demand for RST by directly addressing personal and contextual factors that constrain construction professionals from using RST.
Details
Keywords
Kate Krueger, Adam Stoker and Gabrielle Gaustad
The construction, use and demolition of buildings carry enormous environmental burdens. As one step to reduce a building’s environmental impact, green building design guidelines…
Abstract
Purpose
The construction, use and demolition of buildings carry enormous environmental burdens. As one step to reduce a building’s environmental impact, green building design guidelines and certification programs, such as Leadership in Energy and Environmental Design, Cradle to Cradle and the Whole Building Design Guide, promote the specification of alternative, non-traditional building materials. Alternative materials carry a variety of potential benefits: reducing the amount of energy and other resources needed to create building materials; creating healthier indoor and outdoor environments; diverting or reducing waste from landfills; reducing the use of scarce, critical or economically volatile materials; and spurring innovation in the building industry. However, a lack of clarity surrounds alternative materials and creates a barrier to their usage. The purpose of this paper is to review definitions of alternative materials in various design guidelines in order to provide context to their specification and usage.
Design/methodology/approach
Through a survey of green building programs and guidelines, existing literature on alternative materials, and life-cycle assessment using multiple inventory databases, this study tackles the following questions: what constitutes an alternative building material; what are the current barriers to their specification; how are they specified in the most common design guidelines; and do alternative building materials present a “greener” alternative?
Findings
These results show that while often alternative materials do in fact show promise for reducing environmental impacts of the built environment, by how much can be a challenging question to quantify and depends on a variety of factors. While many green building guides and certification systems provide recommendations for use of alternative materials, the sheer diversity and uncertainty of these systems coupled with the complexity in understanding their impacts still present a significant barrier to their specification. Much work remains in a variety of disciplines to tackle these barriers. A clear emphasis should be on better understanding their environmental impacts, particularly with respect to the context within the built environment that their specification will provide energy, resource and emission savings. Other key areas of significant work include reducing costs, removing regulatory and code barriers, and educating designers, consumers, and end-users.
Originality/value
Alternative materials are defined and specified in a diversity of contexts leaving the design and construction communities hesitant to promote their use; other work has found this to be a key barrier to their widespread usage. By compiling definitions, barriers and design guidelines instructions while also exploring analytically the benefits of specific cases, this work provides a foundation for better understanding where new, more sustainable materials can be successfully specified.
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Balamuralithara Balakrishnan, Natalia Fedorova and Catherina Ugap
The aim of this study is to gauge the consideration toward sustainability and sustainable development in the creative process or activities in design practices among the design…
Abstract
Purpose
The aim of this study is to gauge the consideration toward sustainability and sustainable development in the creative process or activities in design practices among the design undergraduates of University A, Russia, and University B, Malaysia. The beliefs, attitudes and intentions toward all the dimensions of sustainability – environmental, social and economic – were assessed and compared between both institutions.
Design/methodology/approach
A questionnaire was administrated to 127 design undergraduates from University A, Russia, and 135 design undergraduates from University B, Malaysia, to assess their beliefs, attitudes and intentions toward sustainability and sustainability development in their creative practices.
Findings
The outputs of this investigation suggested that the courses related to education for sustainable development that preached in design programs at University A, Russia, have developed appropriate beliefs, attitudes and intentions toward sustainability and sustainable development in creative process or activities among the learners on environmental and social sustainability issues. The subject on sustainable development offered in design programs at University B, Malaysia, has mold positive beliefs, attitudes and intentions on the environmental sustainability issues in creative practices among the design undergraduates. The outcomes of this study shed some light on the effectiveness of the courses related to education for sustainable development of both institutions in building the appropriate mindset in the creative process during design activities.
Originality/value
This study on the consideration of sustainability and sustainable development in creative practices is novel and the outputs of this study can carve the path for an effective education for sustainable development courses in the design programs, specifically in the context of building the appropriate beliefs, attitudes and intentions toward sustainability and sustainable development in creative practices among the future designers.