Andrew Rees

• Swansea University

This study provides insights into the effect of different process parameters on the precision of inkjet printing when producing micro scale features. The parameters examined are printing resolution (which controls the droplets center-to-center distances), printing speed as well as printing mode, whether it is unidirectional or bidirectional. The re...

Reverse engineering (RE) has played a key role in producing low demands parts, especially with the recent advent of robust additive manufacturing (AM) techniques. The synergistic interaction of both cutting-edge RE and AM techniques significantly enhance part re-producing and minimize the product development cycle time, even if there is no blueprin...

This paper aims to identify the capability of a highly flexible industrial robot modified with a high-speed machine spindle for drilling of aluminum 6061-T6. With a focus on drilling feed rate, spindle speed, and pecking cycle, the hole surface roughness and exit burr heights were investigated using the Taguchi design methodology. A state of the ar...

This paper studies the forces acting upon the Intraosseous Transcutaneous Amputation Prosthesis, ITAP, that has been designed for use in a quarter amputated femur. To design in a failure feature, utilising a safety notch, which would stop excessive stress, σ, permeating the bone causing damage to the user. To achieve this, the topology of the ITAP...

This paper aims to identify the capability of a highly flexible industrial robot modified with a high-speed machine spindle for drilling of Aluminum 6061-T6. With a focus on drilling feedrate, spindle speed and pecking cycle, the hole surface roughness and exit burr heights were investigated using the Taguchi design methodology. A state of the art...

The foot orthotic insole market is forecast to surpass a value of 3.6 billion USD by 2021. This vast industry continues to rely on foam milling and other subtractive methods of manufacturing, which have proven to be wasteful and inefficient. Leaps in digital manufacturing have enabled the technology to enter a plethora of industries, with the promi...

During the design and development of ethylene propylene diene monomer (EPDM) exterior automotive seals, prototype components can only manufactured through production tooling platforms by either injection molding or extrusion. Consequently, tooling is expensive and has long lead times. This paper investigates whether additive layer manufacture is a...

The pursuit of polymer parts produced through foam injection moulding (FIM) that have a comparable surface roughness to conventionally processed components are of major relevance to expand the application of FIM. Within this study, 22% talc-filled copolymer polypropylene (PP) parts were produced through FIM using both a physical and chemical blowin...

Recent research in the area of advanced polymer processing has demonstrated the potential of foaming agents to introduce additional functionality within injection molded components. In this research, Talc filled Copolymer Polypropylene (PP) ISO standard tensile bars were produced through low- and high-pressure foam injection molding (FIM). Two chem...

Micro-injection moulding (µ-IM) is a fabrication method that is used to produce miniature parts on a mass production scale. This work investigates how the process parameter settings result in adiabatic heating from gas trapped and rapidly compressed within the mould cavity. The heating of the resident air can result in the diesel effect within the...

Injection moulding is a well-established replication process for the cost-effective manufacture of polymer-based components. The process has different applications in fields such as medical, automotive and aerospace. To expand the use of polymers to meet growing consumer demands for increased functionality, advanced injection moulding processes hav...

Unfilled and Talc filled Polypropylene (PP) tensile bars were produced through low-pressure foam injection molding (FIM). A commercial chemical foaming agent (CBA) was used for the process with varying percentages of 1%, 2% and 5%, of the CBA. The resulting component weight saving was then matched by supercritical N2; a physical blowing agent (PBA)...

Unfilled and talc-filled Copolymer Polypropylene (PP) samples were produced through low-pressure foam-injection molding (FIM). The foaming stage of the process has been facilitated through a chemical blowing agent (C6H7NaO7 and CaCO3 mixture), a physical blowing agent (supercritical N2) and a novel hybrid foaming (combination of said chemical and p...

Direct digital manufacture and additive manufacture have allowed designers the ability to design components without the design limitations witnessed in subtractive manufacturing process routes. In particular, designers can now design parts that fully utilize material usage resulting in a more sustainable and environmentally friendly application of...

Due to the increasing demands on automotive components, manufacturers are relying on injection moulding components from fibre-reinforced polymers in an attempt to increase strength to weight ratio. The use of reinforcing fibres in injection moulded components has led to component failures whereby the material strength is hampered through the format...

Injection moulding (IM) is a well-established manufacturing process for cost-effective replication of polymer-based components. Advanced IM processes have been developed; modifying the final polymer part produced to create microcellular structures. Through the creation of microcellular materials, not only can the final weight be reduced but also, t...

Micro-injection moulding (µIM) is a key technology for scaling down larger geometry components and can include functional features at the micrometre scale and as far as the sub-micrometre length scale. Thermal cycling of amorphous hydrogenated carbon (aC:H) coated Stainless Steel (SS) has been investigated to simulate long-term micro-injection moul...

Advances in additive manufacturing have resulted in significant growth of such materials, including the medical sector. It is particularly applicable to manufacture of prosthetics and implants, where design freedoms and complex geometries afforded by additive manufacturing are especially suited to such products. With this growth it is timely to con...

Microinjection moulding is a key enabling technology for replicating miniaturized components and parts with functional features at the micrometer and even sub-micrometer length scale. The micro moulding tools used in the process chain are critical for delivering high quality parts for the duration of the product life cycle, and recently tool coatin...

Direct digital manufacture and additive manufacture has expanded from rapid prototyping into rapid production and has the possibility to produce personalised high quality products with the batch size of one. Affordable additive manufacturing machines and open source software enables a wide spectrum of users. With a populace empowered with the possi...

As additive manufacturing expands from rapid prototyping into rapid production, it is becoming more important to consider the mechanical performance of candidate products in addition to their functional attributes as a prototype. This study demonstrates how a design of experiments approach can be used to optimise the tensile and notched bending pro...

Pulsed ytterbium-doped fibre lasers based on a Master Oscillator Power Amplifier (MOPA) architecture possess attractive characteristics over their Q-switched diode-pumped solid-state counterparts. These include a relatively low cost of ownership and a flexible operating window with respect to the pulse duration, shape and repetition rate. For micro...

Condition monitoring of micro injection moulding is an effective way of understanding the processing effects of variable parameter settings. This paper reports an experimental study that investigates the characteristics of the demoulding behaviour in micro injection moulding (µ-IM) with a focus on the process factors that affect parts’ quality. Usi...

The paper reports an experimental study that investigates part demoulding behavior in micro-injection moulding with a focus on the effects of pressure and temperature on the demoulding forces. In particular, the demoulding performance of a representative microfluidics part was studied as a function of four process parameters, melt temperature, moul...

This paper investigates the effect that a novel texturing of replication tools by applying amorphous hydrogenated carbon (aC:H) coating has on the processing conditions in micro injection moulding. Texturing usually increases the surface area of tools leading to higher demoulding forces acting on the component during the ejection stage of the proce...

This paper investigates the effect that a novel texturing of replication tools by applying diamond like carbon (DLC) coating has on the processing conditions in micro injection moulding. The research studies the effect that a textured DLC coating with nano scale structures has on the resulting demoulding forces in comparison to an untreated tooling...

In this study the principles of lean manufacture were utilised to generate an improvement plan for an automotive company. In particular, Single Minute Exchange of Dies (SMED) and Value Stream Mapping (VSM) methodologies were combined to enhance the value-added activities time and reduce the non-value added activities within the context of injection...

The effect of adding anti-reflective structures to a PCPDTBT : PCBM organic solar cell on a flexible substrate using a one-step thermal-nanoimprint lithography process has been studied. In order to process nanostructures onto polyethylene terephthalate (PET) substrates, a low glass transition polymer was used. The power conversion efficiency (PCE)...

This paper investigates the technological capabilities of a hybrid micro machining process for performing wire electro-discharge grinding (WEDG). In particular, micro wire electrical discharge machining (μWEDM) is employed in combination with a rotating submergible spindle to perform WEDG. In this research, first a machining strategy for workpiece...

The machining response of metallurgically and mechanically modified materials when processed by employing the microwire electrical discharge machining (microWEDM) technology is reported in this paper. In particular, the effects of the material microstructure on resulting surface integrity of Al5000 series aluminium alloys after microWEDM processing...

The machining response of metallurgically and mechanically modified materials when they are processed by employing the micro wire EDM (μWEDM) technology is reported in this paper. In particular, the effects of the material microstructure on resulting surface integrity of Al5083 series aluminium alloys after μWEDM processing is investigated. The mac...

The introduction of a technique for on-the-machine electrode generation, utilizing wire electro -discharge grinding (WEDG) has broadened the application area of the microelectrode discharge machining ( LEDM) process. The present paper studies the capabilities of the VVEDG process for manufacturing micro -electrodes. 'The influence of electrode mate...

This paper studies the effects of ultrasonic vibration of the tool electrode on the surface integrity of tungsten carbide (WC-10%Co) in the electro-discharge machining (EDM) process. Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), optical microscopy, micro hardness testing and white light interferometery were employed in the...

From among all the different techniques currently applied for micro-manufacturing, this paper focuses on those techniques that can be considered as conventional techniques because of their direct relationship with standard machine tools. The following processes are discussed: ultra-precision milling, thin-wire EDM, die-sinking micro-EDM and diamond...

This paper investigates the technological capabilities of a micro machining process for performing Wire Electro Discharge Grinding (WEDG). In particular, micro Wire Electrical Discharge Machining (µWEDM) is employed in combination with a rotating submergible spindle to perform WEDG. In this paper, the effects of different factors on the achievable...

Apart from the important role that Micromachining and Ultraprecision machining has provided to the development of improved or innovative miniaturised products, these techniques have also attracted the interest of the researchers to obtain the highest accuracy and a thorough analysis of the principles governing the material removing mechanisms. The...