Joseph Chiodo

Shape memory alloy actuators for active disassembly using ‘smart’ materials of consumer electronic products

Abstract 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.

An initial investigation into active disassembly using shape memory polymers

Abstract The aim of the work was to demonstrate an alternative to conventional end-of-life (EOL) disassembly strategies such as robotic or hand dismantling. This initial investigation reports the disassembly of consumer electronic products using smart materials in the design of embedded releasable fasteners. A series of products was tested in a variety of different ways using shape memory polymers (SMPs). Tests were run on macroassemblies and subassemblies of telecommunications goods. The devices designed with SMP used two distinct properties of the material suited to active disassembly: the mechanical property loss (MPL), in this case a loss of rigidity in the thread of the SMP screws; the shape memory effect (SME), a change in form, resulting in this case in the loss of moulded thread from SMP shape memory effect screws. Once SMP components were developed and embedded into the candidate products, timed disassembly experiments were conducted. These tests used infrared, air jet and water bath methods for applying heat to trigger the SMP devices. Once the trigger temperature was reached, shape change and property loss occurred in the screws and brackets, allowing assembly release.

Active disassembly using shape memory polymers for the mobile phone industry

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/spl deg/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.

Preliminary investigations of active disassembly using shape memory polymers

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/spl deg/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.

Electrically self-powered active disassembly

Abstract Active disassembly using smart materials is a concept developed at Brunel University for the design of assemblies with the built-in capability for easy separation of components for recycling on exposure to certain triggering conditions. Such assemblies incorporate shape memory alloy (SMA) actuators in the product housings. These actuators in the form of clips can undergo a shape change (shape memory effect) on going above a transition temperature, and exert a force to effect disassembly. Hitherto, such a change in temperature has been effected by direct heat input external to the assembly. It is now shown in the case of assemblies that contain battery power sources, firstly, that disassembly can be achieved using the residual electrical energy in waste batteries to heat the SMA actuator electrically and, secondly, that there is enough energy left in end-of-life batteries of mobile phones and end-of-life vehicles to trigger at least 4 and 16 devices respectively.

Smart materials use in active disassembly

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 po...

Designing a better tomorrow today with self-disassembling electronics

Publisher Summary .The use of active disassembly using smart materials (ADSM) is an alternative that has the potential to be used for enabling a wide variety of consumer electronics that could be actively assembled, or self-disassembled nondestructively on the same generic dismantling line. This novel form of disassembly has shown considerable promise during the initial tests on the macro- and subassemblies of consumer electronic products. The designer can incorporate smart materials early in the design process, ensuring that at its end-of-life (EOL), perhaps 5 to 10 years later, the product contains all the necessary information and mechanisms to disassemble itself following a single generic triggering event such as heat. Currently, two basic families of smart materials lend themselves to active disassembly: groups of metallic materials known as shape-memory alloys (SMAs) and shape-memory plastics or polymers (SMPs). Most of the active disassembly devices are inexpensive and could prove to be a very valuable investment. Additionally, the smart material actuators and devices are highly reusable.