Conference Paper

Preliminary investigations of active disassembly using shape memory polymers

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Abstract

This paper reports initial results in the application of shape memory polymer (SMP) technology to the active disassembly of electronic products. The smart material SMP of polyurethane (PU) composition was employed. Created for these experiments were novel SMP releasable fasteners, with which it is possible to effectively disassemble products at specific triggering temperatures at the end of their life (EoL). This disassembly technique is termed active disassembly using smart materials (ADSM), and has been successfully demonstrated on a variety of products using other smart materials. Whilst developed primarily as a universal disassembly technique, cost effectiveness is apparent. Heat sources of +70, +100 and +225°C were employed to raise the releasable fasteners above their trigger temperatures: in the case of SMP this would be the glass transition temperature (Tg). The development of releasable fasteners and applications in electronic products is described

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... A number of factors during the design phase must be considered to make ADSM a feasible EoL option. These factors include: functional requirements of the SMM component, the method of triggering, and the cost of the component, and ease for servicing [3,19,[21][22] . ...
... This may mean that an assembly with SMM components may be more expensive compared to traditional assemblies, but with the use of two-way SMAs and SMPs this may not be the case. These two-way SMAs and SMPs can be retrained and thusly reused in subsequent assemblies meaning the cost of use for these SMM may in fact become much lower than regular engineering materials [19] . Of the two SMMs, SMPs exhibit a higher range of reusability and because they are often the least expensive of the SMMs; SMPs have become the most feasible option for ADSM [26] . ...
... SMP MPL Screws[18] SMP MPL screw in Product Assembly[18] Disassembled Sony CD Player using MPL screws[19] ...
... Product-embedded disassembly gives a product the ability to take itself apart. Chiodo et al [2] demonstrated the feasibility of a self-disassembly strategy for consumer electronic products using fastener screws made of a special shape memory alloy (SMA) polymer. ...
... Product-embedded disassembly gives a product the ability to take itself apart. Chiodo et al [2] demonstrated the feasibility of a self-disassembly strategy for consumer electronic products using fastener screws made of a special shape memory alloy (SMA) polymer. Masui et al [1] demonstrated the self-disassembly of a CRT using nichrome wire embedded in the component glass along the desired boundary for separation. ...
Conference Paper
Full-text available
Disassembly is a fundamental process needed for component reuse and material recycling in all assembled products. Integral attachments, also known as "snap" fits, are favored fastening means in design for assembly (DFA) methodologies, but are not necessarily a favored choice for design for disassembly. Several prototype designs of a new class of integral attachments are presented, where the snapped joints can be disengaged by the application of localized heat sources. The design problem of reversible integral attachments is posed as the optimization of compliant mechanisms actuated with localized thermal expansion of materials. The Homogenization Design Method is utilized to obtain an optimal structural topology that realizes a desired deformation of snapped features for joint release. The obtained optimal topologies are simplified to enhance the manufacturability for the conventional injection molding technologies. Results of the example designs are verified by finite element analyses
... Throughout the six weeks of the summer that this program lasted, I was working on a research project titled "Study of the behavior of Shape Memory Polymers in the Active Disassembly Process" under the supervision of Dr. Hua Li. This project focused on active disassembly using smart materials (ADSM) as an alternative, with the potential to enable a broad range of electronic devices to be actively disassembled at the same time, reducing the cost of the manual labor or machine operation needed to disassemble the products [1][2][3][4][5] . One of the main aspects of this project that excited and motivated me the most was to be working with smart materials such as Shape Memory Polymers 6 (SMPs). ...
... [1][2][3] Since 1990s, active disassembly, as a non-destructive, low-cost and environment-friendly dismantling technique, has been widely researched, and applied to a variety of small-sized electrical and electronic products. [4][5][6][7][8][9][10][11][12] However, present researches almost focus on the active disassembly in single physical field, especially in temperature field. These methods can achieve disassembly easily, but hardly guarantee that products will not be accidentally triggered during normal use. ...
Article
The paper put forward to active disassembly, multi-step active disassembly methods and design criteria based on electro and heat stimulation. General design method of active disassembly product based on electro and heat stimulation was explained through the case analysis. Finite element analysis results are compared with experimental ones, electro and heat stimulation experiments were compared with the traditional heat stimulation experiments, and then the feasibility of method was proved. Active disassembly method and the design criterion were used in active disassembly design of products, disassembly efficiency for products are improved obviously.
... Incorporation of these screws has been seen in Chiodo et al. [10], where Nokia 6110 and Nokia Populus cell phones were retrofitted and disassembled by the screws. Chiodo et al. [11] also used these screws in a retrofitted game controller, clock radio, and CD player for disassembly. Beyond SMP compression sleeves and SMP MPL screws the Cleaner Research group has also looked at other designs that go beyond retrofitting existing products. ...
Conference Paper
Full-text available
Disassembly is becoming a mandatory step in the end-of-life processing for electronic products. More and more regulations call for the removal of hazardous materials and mandate the recovery of components and recyclable materials. It is then no surprise that research has continually looked for more efficient methods of disassembly. Of these methods, active disassembly is at the forefront. Active disassembly incorporates innovative fasteners, which under a special environmental condition will exhibit a disassembling or releasing action. The use of smart materials, more specifically shape memory alloys and shape memory polymers, has been extensively documented. For shape memory polymers, past research has shown innovative designs, such as thread-losing screws and deformable brackets. What has not been shown with shape memory polymers, however, is one of the most basic and common fasteners-the snap-fit. This paper examines the design and processing method for creating a shape memory polymer snap-fit and demonstrates its effectiveness as an actively disassembling fastener.
... Taya et al. fabricated the SMA/SMP composite by mixing epoxy resin and curing agent in a Teflon mold and curing overnight [29]. Chiodo et al. fabricated a small number of screws (less than 1000) used for fast disassembly by potting and curing in a silicone mold [30]. ...
Article
Full-text available
This article presents a novel method of shape memory polymer (SMP) processing for additive manufacturing, in particular, fused-deposition modeling (FDM). Critical extrusion process parameters have been experimented to determine an appropriate set of parameter values so that good-quality SMP filament could be made for FDM. In the FDM process, effects of different printing parameters such as extruder temperature and scanning speed on object printing quality are also studied. In all the process studies, we aim to achieve good-quality parts by evaluating part density, tensile strength, dimensional accuracy, and surface roughness. Based on these studies, sample SMP models have been successfully built. Due to the thermal sensitive nature of the printed SMP parts, they can potentially be used as fasteners in active assembly/disassembly, smart actuators, deployable structures for aero-space applications, etc.
... In recent years, with the deep research and extensive application of smart materials, the method of Active Disassembly using Smart Materials (ADSM) is getting more and more concerns [6][7][8][9][10]. The technology of ADSM was put forward by Dr. Chiodo in Brunel University at 1997. ...
... Moreover, it was predicted that only active disassembly has the potential to shift an EoL treatment with systematic disassembly from a cost factor to a profit generating activity [40,42]. The most extensive research on active disassembly yet is based on shape memory materials [43][44][45][46][47][48][49]. Both the use of thermally triggered Shape Memory Alloys (SMA) and Shape Memory Polymers (SMP) for the concept of AD have been thoroughly investigated in prior research [43,44,47,[50][51][52][53][54][55]. ...
Article
This paper presents a number of novel active fasteners developed to significantly lower disassembly costs during reconditioning, remanufacturing, and recycling of products. In the initial stage of the fastener development process, the applicability of distinct trigger signals for active disassembly (AD) is evaluated. Based on this evaluation, the high robustness of using a pressure increase or decrease as a nondestructive trigger for AD is demonstrated. Since previously proposed pressure-sensitive fasteners face considerable drawbacks upon implementation in electronic products due to the ongoing trend of miniaturization, a second generation of pressure-based active fasteners is developed. Evaluation of these fasteners by means of axiomatic design techniques and prototyping demonstrates that the presented snap-fits, which make use of a closed-cell elastomer foam, are most robust. Subsequently, the contraction forces that closed-celled foams can exert as a function of an increase in ambient air pressure are experimentally determined. Furthermore, the implementation of pressure-sensitive foam-based snap-fits in both a modem and a payment terminal is described. Results of these experiments demonstrate that the contraction force of a cross-linked metallocene polyethylene closed-cell foams can reach up to 6 N/cm2 at an overpressure of 2 bar and that the foam-based snap-fits can be released at a pressure increase of 2 bar.
... TRIZ, a problemsolving, analysis and forecasting tool derived from the study of patterns of inventions in the global patent literature, contains different interesting trends which can be related to the evolution of fasteners and electronic products, such as [19]: -Smart materials: from passive to fully adaptive fasteners, e.g. made out of shape memory materials. The most advanced research on active disassembly yet is based on materials which are able to return to an initial shape when heated above the trigger temperature [20][21][22][23][24][25]. -Object segmentation: from monolithic solid fasteners to a segmented solid up to a vacuum to hold an assembly together. ...
Article
Full-text available
The principle of Active Disassembly (AD), in which innovative reversible fasteners can be simultaneously activated by an external trigger signal, enables a promising End-of-Life (EoL) treatment for electric and electronic products. Therefore, the economic and environmental constraints for implementing AD are discussed, as well as the information requirements for AD. Furthermore, the potential benefits of properly implementing active fasteners in a Liquid Cristal Display (LCD) and a Plasma Display Panel television are presented based on a case study.
... In the early attempts for active assembly/disassembly, conventional SMMs were applied. For instance, the feasibility studies for active disassembly of various electrical devices conducted at Brunel University, UK, Katholieke Universiteit Leuven, Belgium and Nokia Research Center are based mainly on SMAs and SMPs (occasionally using engineering polymers around 2000-2002 at Brunel University) (Chiodo et al., 1998b(Chiodo et al., , 1999(Chiodo et al., , 2000(Chiodo et al., , 2001Tanskanen, 2003;Carrell et al., 2009;Duflou et al., 2006). ...
Article
Full-text available
Purpose – This paper aims to present a review on utilizing shape memory technology (SMT) for active assembly/disassembly, i.e. assembly/disassembly without physically touching. Design/methodology/approach – The fundamentals behind the shape memory effect (SME) in materials, in particular shape memory alloys (SMAs) and polymers, which are the cornerstones of SMT, are introduced, together with the possible approaches to implement this effect in active assembly/disassembly. Example applications for not only active assembly/ disassembly, but also programmed active disassembly are presented. Findings – The advantages of utilizing SMT over conventional assembly/disassembly techniques are identified. Originality/value – The paper introduces the fundamentals behind the SME and the basic approaches to implement the SMT in not only active assembly/disassembly, but also programmed active assembly.
... Their first studies used SMA alloy coils and rods that would forcefully open and separate a product's components upon a thermal trigger [1][2][3][4][5]. Their AD studies with SMPs have used manufactured screws that lose their threading upon a thermal trigger and LCD brackets that will release a LCD upon a thermal trigger [6][7][8][9]. ...
Article
Full-text available
This paper explores a means to control the active disassembly (AD) process for designed and manufactured heat-activated shape memory polymer snap-fits. Testing was performed for demonstration of the active release of the SMP snap-fits and for analysis of AD control factors. Robust design methodologies with Taguchi methods were used to analyze the AD process factors, including heating method and disassembly temperature. The results from this research show the successful demonstration of the SMP snap-fits. AD process analysis shows that both the heating method and temperature affect the AD process. The analysis determines that by increasing the heat exchange rate the snap-fit disassembly time is shortened. From the performed experiments, it was seen that an Oil bath at 150°C produced the best results in regards to disassembly time and signal-noise ratio.
... At ambient temperatures, the SMP screws function like regular screws, and at elevated temperatures, the screws lose their threading to release from the product. Retrofitting of these screws has been done in a number of AD studies for electronic products (Chiodo et al.,1999a,b;Chiodo et al.,inpress). Beyond retrofitting with SMP compression sleeves screws, the Cleaner Research group has also looked at original element designs for specific product applications, such as an LCD bracket that will release upon a thermal trigger (Chiodo et al., 2000). ...
... Productembedded disassembly gives a product the ability to take itself apart. Chiodo et al [30]demonstrated the feasibility of a self -disassembly strategy for consumer electronic products using fastener screws made of a special shape memory alloy (SMA) polymer. Masui et al [31] demonstrated the self disassembly of a CRT using nichrome wire embedded in the component glass along the desired boundary for separation. ...
Article
Full-text available
Thermal transducers, which can be interpreted as thermally actuated compliant mechanisms, have found a wide range of applications, due to the reason of accessible source, easy controllability and reliability. During the past decade topology optimization techniques have been developed as efficient tools to design distributed type of complaint mechanisms. The generated results have been accepted and applied in practical applications. There has been research done to synthesize design of thermal actuation embedded electrical-thermal-compliant mechanisms, in which the non-uniform joule heating was generated through non-uniform electric current. In this research, time transient effect of heat transfer is proposed to produce the localized thermal actuation, while only simple forms of boundary heating is considered. Therefore non-uniform temperature distribution can be achieved by controlling the heating time before steady state is reached. This technique can be applied to design a novel type of integral attachment mechanisms to realized product-embedded disassembly. Design of heat-activated reversible snap-fit is posed as a topology optimization problem of compliant mechanism actuated with localized thermal expansion of materia ls through time transient heat transfer within the structure. Homogenization Design Method is utilized to calculate the effective material properties during the material distribution. Optimal configuration is presented, and in order to enhance manufacturability, simplification scheme and adjustment are applied to obtain realizable model. Final design is further verified with commercial FEA software.
Chapter
Waste Electrical and Electronic Equipment (WEEE) is one of the most significant waste streams in modern societies. In the past decade, disassembly of WEEE to support remanufacturing and recycling has been growingly adopted by industries. With the increasing customization and diversity of Electrical and Electronic Equipment (EEE) and more complex assembly processes, full disassembly of WEEE is rarely an ideal solution due to high disassembly cost. Selective disassembly, which prioritizes operations for partial disassembly according to the legislative and economic considerations of specific stakeholders, is becoming an important but still challenging research topic in recent years. In order to address the issue effectively, in this chapter, a particle swarm optimization (PSO)-based selective disassembly planning method embedded with customizable decision-making models and a novel generic constraint handling algorithm has been developed. With multi-criteria and adaptive decision-making models, the developed method is flexible to handle WEEE to meet the various requirements of stakeholders. Based on the generic constraint handling and intelligent optimization algorithms, the developed research is capable to process complex constraints and achieve optimized selective disassembly plans. Industrial cases on liquid crystal display (LCD) televisions have been used to verify and demonstrate the effectiveness and robustness of the research in different application scenarios.
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In this article, we present a brief review about polymeric shape memory materials (SMMs) and typical applications of these materials for functioning as actuators. A couple of generic working mechanisms to enable the shape memory effect (SME) in materials are introduced, together with some relatively new shape memory phenomena, such as the multiple-SME, temperature memory effect (TME), mechano-responsive SME, etc. It is revealed that now we are able to not only design/syntheses a polymeric material, but also to tailor its performance to well meet the requirement(s) of a particular application. It is concluded that the shape memory technology (SMT) provides us a powerful tool to produce far greater impact to reshape both product design and fabrication.
Article
Full-text available
Reversible fasteners suited for Active Disassembly (AD), which can be simultaneously released by an increase in ambient air pressure, have been developed in prior research. However, the implementation of these active fasteners in electronic consumer products is hampered as a result of the ongoing trend of miniaturization. Therefore, a second generation of pressure based fasteners was developed in line with the evolutionary TRIZ trends. This paper presents a novel pressure sensitive snap-fit for electronic products which makes use of closed cell elastomer foam and releases at an overpressure of 2 bar.
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Active disassembly products often use active disassembly structures triggered by single temperature or pressure field as reversible joints. These structures can be triggered automatically in extreme or accidental circumstances, thus causing the low reliability of products. For improving the reliability of active disassembly products, working mechanisms of active disassembly structure triggered by temperature-pressure coupling is presented in this article. Through analyzing some typical active disassembly structures, this article presents the design criteria and methods of active disassembly structure triggered by temperature-pressure coupling. The feasibility of these design methods is proved by a case analysis. The results of research shows that the reliability of active disassembly structures triggered by temperature-pressure coupling is improved greatly, which can lay the foundation for the industrial applications of active disassembly methods.
Article
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Article
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Article
Due to the characteristic that shape memory materials can quickly return to their original shape and have large deformation, such materials can be used as the connection in active disassembly devices. However, existing active disassembly devices typically require two moulding steps and complicated machining processes that result in high manufacturing cost. The active disassembly device based on the proposed decapitated head method has only one moulding step and lower manufacturing cost. Its disassembly mode is local damage disassembly, which can decrease the active disassembly cost and improve disassembly efficiency. This paper describes the active disassembly theory and the design methodology based on the decapitated head method, and then analyses the design criteria and feasibility of this method with a real case study.
Article
Purpose Smart materials (SMs) have the potential for facilitating active disassembly (AD). Select SMs are used in the design of devices to aid product disassembly. The purpose of this paper is to compare different AD approaches and highlight future work and potential. Design/methodology/approach This work is a survey of the collated AD research employing only Smart and “made Smart” materials work from various published work in the field from companies and academia since its original invention. The introduction gives general discussion of AD with cost implications and how the technology could offer very lean dismantling. An overview of the history of the work is given with the context of the implications for the need for a technology like AD to retain critical materials. Findings Besides a survey to date, comparisons were made of each AD technology application highlighting advantages and challenges. Comparisons were also made prior to this in alternative disassembly strategies to give context to the potential usefulness of the technology. Practical implications Only AD with SMs or “made Smart” were highlighted with some considerations for potential candidates. Originality/value A survey of AD work only employing SMs and “made‐Smart” materials to date. Comparisons of each AD application were made highlighting advantages and challenges. Comparisons were made between AD and alternative disassembly strategies to give context to the potential usefulness of the technology. The conclusion included an overview of work with consideration for future work. A candidate technology with the most potential was discussed.
Article
Full-text available
Disassembly has been widely accepted as a disadvantageous end-of-life activity, but with increasing pressures from directives, such as waste on electrical and electronic equipment, and with increasing pressures to become sustainable disassembly is becoming necessary. Current disassembly methods, including both manual and automated disassembly, need improvements to meet this necessity. This paper will introduce the improvements needed and suggest through literature the validity of active disassembly (AD) to provide these improvements. Past and current research will also be considered to provide a future path for AD. This future path for AD will consider a collaborative effort to solve problems with materials, environmental triggers and costs seen with AD.
Technical Report
Full-text available
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Full-text available
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Chapter
Active disassembly technology provides the designer a useful unmanned disassembly processes to achieve efficient recycling for products. Currently, many types of smart active fasteners are developed by using shape memory plastics (SMP). This technology has been testing in cell phones and LCD TVs to confirm the concepts. This paper presents an eco-innovative design methodology by using TRIZ method to innovate the new concepts of smart active fasteners for active disassembly at the end-of-life stage of products. The tools of TRIZ, such as contradiction matrix, inventive principles, and substance-field analysis, are chosen in this study to develop this eco-innovative design methodology. Examples are demonstrated to illustrate the capability of proposed methodology.
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Active disassembly using smart materials is a relatively new technology. Extensive tests have shown that the technology works. Analysis of product categories indicates that plastics dominated products as well as precious metals dominated products are most likely to benefit from including active disassembly in their end-of-life strategies. The economic implications of doing so are investigated. In principle, active disassembly will turn out much cheaper than conventional disassembly, and will greatly reduce processing times as well as improve specifications of output fractions. Further testing with respect to determining the ecological advantage is needed, but it is believed that considerable gains may apply here also.
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A series of cyclic thermo-mechanical measurements was conducted on segregated poly(ester urethane) to study substantial changes in triple-shape properties as a result of hydrolytic aging (80 °C). Prior to the analysis of aging effects, a concept of triple-shape testing was elaborated, starting with the implementation of two distinct programming units. The first one included a deformation at 60 °C to ɛm1 = 100% (temporary shape B) and its fixing through soft segment crystallization by cooling to −20 °C under constant strain. The second one consisted of a deformation at −20 °C to ɛm2 = 200% (temporary shape A) and its stabilization through soft segment vitrification as achieved by cooling to −60 °C under fixed strain constraint. Then, gradual heating of the polymer from below to above its thermal transition temperatures gave two independent shape recovery responses in the reverse order of shape fixing: A → B through passing the glass transition by heating from −60 to 23 °C and B → C (back to the permanent shape), when heating the material from 23 to 60 °C and thus above its soft segment melting temperature. In a progressive approach, the storage of loading history through the sequential fixing of two temporary shapes was proven by the development of shape recovery stresses under constrained environment. With the implementation of the two testing methods several aging-related effects could be detected. Good shape fixing abilities ≥90% for both shapes were found and contrasted by significant changes in shape recoverabilities and stress storage capacities. Further insights derived from differential scanning calorimetry (DSC) measurements, indicating an aging-related growth in soft segment crystallinity, and dynamic mechanical analysis (DMA), suggesting a plasticizer effect of water onto the polymer matrix and that aging favoured an increase in cross-linking density.
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This paper reports the preliminary to current development of Shape Memory Alloy (SMA) actuators within their application in ‘Active Disassembly using Smart Materials’ (ADSM). This non-destructive self-dismantling process is to aid recycling of consumer electronic products. Actuators were placed in single and multi-stage hierarchical temperature regimes after being embedded into macro and sub-assemblies of electronic product assemblies. Findings include active disassembly and a hierarchical dismantling regime for product dismantling using developed SMA actuators embedded into candidate products.
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Recent legislative and social pressures have driven manufacturers to consider effective part reuse and material recycling at the end of product life at the design stage. One of the key considerations is to design and use joints that can disengage with minimum labor, part damage, and material contamination. This paper presents a unified method to design a high-stiffness reversible locator-snap system that can disengage nondestructively with localized heat, and its application to external product enclosures of electrical appliances. The design problem is posed as an optimization problem to find the locations, numbers, and orientations of locators and snaps as well as the number, locations, and sizes of heating areas, which realize the release of snaps with minimum heating area and maximum stiffness while satisfying any motion and structural requirements. The screw theory is utilized to precalculate a set of feasible orientations of locators and snaps, which are examined during optimization. The optimization problem is solved using the multiobjective genetic algorithm coupled with the structural and thermal finite element analysis. The method is applied to a two-piece enclosure of a DVD player with a T-shaped mating line. The resulting Pareto-optimal solutions exhibit alternative designs with different trade-offs between the structural stiffness during snap engagement and the area of heating for snap disengagement. Some results require the heating of two areas at the same time, demonstrating the idea of a lock-and-key.
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The European Union draft Waste Electrical and Electronic Equipment (WEEE) directive calls for the removal and separate treatment of liquid crystal displays (LCD). This aspect of the legislation will potentially have an important impact upon the future `End of Life' (EoL) processing of much WEEE. Active Disassembly using Smart Materials (ADSM) has been proven to have applicability in self-dismantling, nondestructive and rapid disassembly of small electronic products. This paper investigates the technical feasibility of removing LCD screens from IT communication products using ASDM technology. In this paper an option is suggested to cleanly separate LCD screens from printed circuit boards, utilizing an LCD bracket made from `shape memory polymer'. The case study products employed are Nokia Japanese J-Phones. Demonstration experiments with initial results are presented, and future developments discussed. SMB glass transformation temperatures (Tg) and time efficiency in disassembly are considered
Conference Paper
This paper reports results the application of shape memory polymer (SMP) technology to the active disassembly of modern mobile phones. The smart material SMP of polyurethane (PU) composition was employed. Two different types of SMP fasteners were created for these experiments. With these smart material devices, it is possible for products to disassemble themselves at specific triggering temperatures at EoL. The two designs were compared for disassembly effectiveness. The disassembly technique is termed active disassembly using smart materials (ADSM), and has been successfully demonstrated on a variety of mobile phones. Whilst developed primarily as a universal disassembly technique, cost effectiveness and time performance is apparent. Heat sources of +90, +100 and a range of +67 to +120°C were employed to raise the releasable fasteners above their trigger temperatures: in the case of SMP this would be the glass transition temperature (Tg). The development of releasable fasteners and applications in electronic products is described
Conference Paper
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Industrial recycling is a practice of growing importance while impending `Take Back' European legislation and economic pressures are increasing. Landfill sites are becoming exhausted and the industry could benefit from a novel approach to recycling pre and post consumer waste. Cost constraints limit the number of different products that can be recycled. Recyclers are working on broadening the range of reusable components from this waste stream, but the proposed approach would significantly increase the volume of recyclable material used in manufacturing new products. This alternative could potentially reduce recycling cost per product in the event of mandatory recycling as a wide variety of consumer electronics could be actively or self disassembled on the same generic dismantling line. The use of Shape Memory Alloy (SMA) actuators in a wide variety of consumer electronic products in the same dismantling facility was tested. The candidate products had undergone a multi-stage hierarchical temperature regime on their macro and subassembly disassemblies and results reported. Two forms of SMA actuators were employed in the designs of actuators; these were one-way Nickel-Titanium (NiTi) and two-way Copper-Zinc-Aluminum (CuZnAl) actuators
Book
This is a new and up-to-date edition of a standard reference work in which the specialist terms of a wide range of sciences and technologies (including textile technology) are listed and explained. Such a reference work is of increasing importance in a world where the terminology of individual sciences and technologies is met with increasing frequency in other sciences and technologies. A number of appendices contain useful additional information including SI (internationally agreed basic units) conversion factors.
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