ETCbrunel provides a highly regarded consultancy and research service in engineering and environmental investigations, including expert witness statements for legal purposes. http://bura.brunel.ac.uk/handle/2438/272 2013-05-21T21:27:31Z 2013-05-21T21:27:31Z Huda, Z Shi, KW Bulpett, R http://bura.brunel.ac.uk/handle/2438/7346 2013-04-08T14:04:20Z 2009-01-01T00:00:00Z

Title: Failure analysis of a steel motorcycle kickstand Authors: Huda, Z; Shi, KW; Bulpett, R Abstract: A fractured steel motorcycle kickstand was metallurgically investigated using a range of failure analysis tools [visual examination, energy dispersive X-ray (EDX) analysis, electron microprobe analysis (EPMA), scanning electron microscopy (SEM), fractography, optical microscopy, hardness testing and non-destructive testing (NDT)]. The steel kickstand’s composition, its microstructure, electron fractographs, and mechanical test results have been critically interpreted. Some evidence of wear damage, in the failed kickstand, was observed. The microstructural and fractographic analyses showed pre-existing micro-cracks which were believed to have grown to result in ductile failure followed by acceleration of corrosion. Recommendations have been made to avoid the failure of the motorcycle kickstand. Description: Copyright @ 2009 Springer US.

2009-01-01T00:00:00Z Bacon, Simon Richard http://bura.brunel.ac.uk/handle/2438/7039 2012-12-17T10:49:42Z 2012-01-01T00:00:00Z

Title: Interactions between latent fingermarks, deposition surfaces and development agents Authors: Bacon, Simon Richard Abstract: Fingerprints have provided a crucial source of forensic evidence for well over a century. Their power lies in an inherent ability for human identification and individualisation, which is based on two fundamental properties: uniqueness and lifelong permanence. Latent fingermarks represent by far the most evidentially common and challenging form of deposition, whereby an invisible copy of the unique friction ridge fingertip pattern is left as an amalgamated secretory residue on any surface that is touched. Dry powder dusting, the first and most iconic method for visualising or developing these deposits, was developed in the latter part of the 19th Century. In the period since, a great number of additional techniques, utilising physical, chemical and optical interactions in isolation or combined, have been devised for the same purpose. By selecting the correct technique in the correct order, it is now possible to extract significant print details from an unprecedented variety of surfaces. In the UK, such operational choices are recommended via Home Office issued protocol tables, which offer an optimum guide based on substrate type, substrate properties and fingermark conditions. Development technique specificity has improved in the last half-century alongside increased biochemical understanding of residue composition, however, the shear variety of potential deposition substrates that exist within a heavily industrialised world inevitably causes disparities in efficiency, even within single protocol classifications. These effects are compounded by the enormous potential for pre- and post-deposition residue composition variation, relating to donor factors (age, sex, diet, lifestyle, etc.) and time dependant changes (environmental, biological, etc.) respectively. As a result, routine technique application can cause sub-optimal development. This research utilises high resolution imaging and analysis techniques to demonstrate how subtle surface chemistry and topography features can selectively influence routine technique efficiency within a single protocol classification (smooth, nonporous plastics). Titanium dioxide, a widely used white pigment, has been shown as prevalent in a range of polymers following SEM and EDX analysis, either in a patchy or ubiquitous distribution. SEM analysis demonstrates a strong interaction between the pigment and carbon powder suspension, which causes detrimental overdevelopment effects in off-ridge areas. ToF-SIMS mapping of a Formica substrate places a significant amount of patchy distributed titanium dioxide in the top 30nm of the surface. Mapping also indicated the presence of an aluminosilicate pigment coating; however, it’s involvement in the possible surface potential or surface energy interaction mechanism is unknown The effects of linear surface features, which have previously been implicated in off-ridge cyanoacrylate overdevelopment on two operationally relevant polymers, were also analysed by creating a silicon wafer model for micro-FTIR analysis. Fingermark residues, including hydroxyl groups, have been shown to migrate significant distances along induced scratches in the model substrate over a 48hr period. It is likely that observed overdevelopment along large valley-like features (uPVC) and scratches (polyethylene) in the operationally relevant polymers is caused by a similar migration of residues. Description: This thesis was submitted for the degree of Master of Philosophy and awarded by Brunel University.

2012-01-01T00:00:00Z Podgoric, S Jones, BJ Bulpett, R Franks, J Troisi, G http://bura.brunel.ac.uk/handle/2438/6729 2012-09-25T10:56:31Z 2009-01-01T00:00:00Z

Title: Structure and tribological performance of diamond-like carbon based coatings for aerospace component processing Authors: Podgoric, S; Jones, BJ; Bulpett, R; Franks, J; Troisi, G Abstract: This work examines diamond-like carbon (DLC) coatings deposited by plasma enhanced chemical vapour deposition (PECVD) as an environmentally friendly alternative to chromium plating in restoration of worn or damaged aircraft components. DLC coatings offer superior mechanical properties; however, high internal stresses and poor adhesion can prevent the deposition of thick films. This work examines a series of layered structures based on epoxy-resin interlayers with DLC applied as a surface film. Wear testing and examination with scanning electron microscopy and atomic force microscopy lead to the development of an optimum DLC/epoxy system with wear characteristics superior to those of chromium-plated steel. This new coating system has a great potential in restoring aircraft components in a more efficient and environmentally friendly manner. Description: Copyright @ 2009 The Surface Science Society of Japan

2009-01-01T00:00:00Z Glot, AB Sandoval-García, AP Gaponov, AV Bulpett, R Jones, BJ Jimenez-Santana, G http://bura.brunel.ac.uk/handle/2438/5636 2012-01-23T10:58:35Z 2009-01-01T00:00:00Z

Title: Electronic properties of SnO2-based ceramics with double function of varistor and humidity sensor Authors: Glot, AB; Sandoval-García, AP; Gaponov, AV; Bulpett, R; Jones, BJ; Jimenez-Santana, G Abstract: Tin dioxide based varistor ceramics SnO2-Co3O4-Nb2O5-Cr2O3-xCuO (x=0; 0.05; 0.1 and 0.5) were made and their electrical properties were studied. The highest nonlinearity coefficient and electric field (at current density 10-3 A cm-2) were obtained for 0.1 mol.% CuO addition. It was observed that low-field electrical conductivity is increased with relative humidity, therefore, materials obtained exhibit double function of varistor and humidity sensor. The highest humidity sensitivity coefficient is found for SnO2-Co3O4-Nb2O5-Cr2O3 ceramics (without CuO). Observed varistor and humidity-sensitive properties are explained in the frames of grain-boundary double Schottky barrier concept as a decrease of the barrier height with electric field or relative humidity. Using suggested simple theory and data obtained on isothermal capacitance relaxation, the energy of the grain-boundary monoenergetic trapping states were estimated. These values are less than found for activation energy of electrical conduction (as a measure of the barrier height). These observations confirm the barrier concept. Description: This is the post-print version of the article. The official published version can be obtained from the link below - Copyright @ 2010 AD-Tech.

2009-01-01T00:00:00Z