Abrasive wear resistance of electroless Ni-P coated aluminium after post treatment

Electroless nickel (EN) coatings are recognised for their hardness and wear resistance in automotive and aerospace industries. In this work, electroless Ni–P coatings were deposited on aluminium alloy substrate LM24 (Al–9 wt.% Si alloy) and the effect of post treatment on the wear resistance was studied. The post treatments included heat treatment and lapping with two different surface textures. Scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD) and micro-abrasion tester were used to analyse morphology, structure and abrasive wear resistance of the coatings. Post heat treatment significantly improved the coating density and structure, giving rise to enhanced hardness and wear resistance. Microhardness of electroless Ni–P coatings with thickness of about 15 μm increased due to the formation of Ni3P after heat treatment.

Deposit-feeding mechanisms and resource partitioning in tropical holothurians

Aspidochirote holothurians found on tropical reef flats feed on particulate deposits which form a variety of substrata. The synaptid holothurian Opheodesoma grisea (Semper) feeds in a similar manner by scraping deposits from the surfaces of sea grasses. Distributional and gut content analyses showed that species partitioning is on the basis of substratum and particle size preference. Scanning electron microscopy revealed that the tentacles of aspidochirotes have a nodular surface while those of O. grisea have a tessellated surface structure. The twelve different species examined were shown to have different tentacular surface textures which bore an apparent relationship with the mean particle sizes selected by the different species. Light microscope studies of tentacle sections confirmed earlier observations on the extent of the water vascular system in aspidochirote and pinnate tentacles. From these observations a functional interpretation is proposed for tentacular operation and the means of particle selection in such holothurians.

Fauna

Stapleton’s self designed instrument, the BoSS (Bonsai Sound Sculpture, 2010) combines with Rose’s circular breathed baritone, multi-phonic and harmonic textures, to explore other sound worlds through real time interaction/composition. The method of exploration commits to a free improvisation aesthetic whereby the music is created at the point of performance. Encountering one another’s music while performing at the ‘Call them Improvisers’ performance at SARC, an ensemble directed by Evan Parker (November 2010) an affinity to the possibilities of one another’s particular approach became immediately apparent. This strongly identified connection led them to further explore the musical possibilities within the parameters created by the duo setting. Duo activities include concerts at Ausland (Berlin), SARC (Belfast), Sowieso (Berlin), Wendel (Berlin), and a recording with Elmar Susse in Hoffnungskirche, Pankow released by the California-based pfMENTUM record label in 2013.

This output is published in the form of an audio CD on the pfMENTUM record label.

Microstructure evolution of 6061 O Al alloy during ultrasonic consolidation:An insight from electron backscatter diffraction

6061 O Al alloy foils were welded to form monolithic and SiC fibre-embedded samples using the ultrasonic consolidation (UC) process. Contact pressures of 135, 155 and 175 MPa were investigated at 20 kHz frequency, 50% of the oscillation amplitude, 34.5 mm s sonotrode velocity and 20 °C. Deformed microstructures were analysed using electron backscatter diffraction (EBSD). At all contact pressures deformation occurs by non-steady state dislocation glide. Dynamic recovery is active in the upper and lower foils. Friction at the welding interface, instantaneous internal temperatures (0.5-0.8 of the melting temperature, T), contact pressure and fast strain rates result in transient microstructures and grain size reduction by continuous dynamic recrystallization (CDRX) within the bonding zone. Bonding occurs by local grain boundary migration, which allows diffusion and atom interlocking across the contact between two clean surfaces. Textures weaken with increasing contact pressure due to increased strain hardening and different grain rotation rates. High contact pressures enhance dynamic recovery and CDRX. Deformation around the fibre is intense within 50 μm and extends to 450 μm from it. © 2009 Acta Materialia Inc.

Infrastructure and the Architectures of Modernity in Ireland 1916-2016

At the formation of the new Republic of Ireland, the construction of new infrastructures was seen as an essential element in the building of the new nation, just as the adoption of international style modernism in architecture was perceived as a way to escape the colonial past. Accordingly, infrastructure became the physical manifestation, the concrete identity of these objectives and architecture formed an integral part of this narrative. Moving between scales and from artefact to context, Infrastructure and the Architectures of Modernity in Ireland 1916-2016 provides critical insights and narratives on what is a complex and hitherto overlooked landscape, one which is often as much international as it is Irish. In doing so, it explores the interaction between the universalising and globalising tendencies of modernisation on one hand and the textures of local architectures on the other.

The book shows how the nature of technology and infrastructure is inherently cosmopolitan. Beginning with the building of the heroic Shannon hydro-electric facility at Ardnacrusha by the German firm of Siemens-Schuckert in the first decade of independence, Ireland became a point of varying types of intersection between imported international expertise and local need. Meanwhile, at the other end of the century, by the year 2000, Ireland had become one of the most globalized countries in the world, site of the European headquarters of multinationals such as Google and Microsoft. Climatically and economically expedient to the storing and harvesting of data, Ireland has subsequently become a repository of digital information farmed in large, single-storey sheds absorbed into anonymous suburbs. In 2013, it became the preferred site for Intel to design and develop its new microprocessor chip: the Galileo. The story of the decades in between, of shifts made manifest in architecture and infrastructure from the policies of economic protectionism, to the opening up of the country to direct foreign investment and the embracing of the EU, is one of the influx of technologies and cultural references into a small country on the edges of Europe as Ireland became both a launch-pad and testing ground for a series of aspects of designed modernity.

Ravel’s Gaspard de la Nuit: Extra-musical subtext, and its role within interpretive performance

Few works within the realm of the piano repertoire have amassed a reputation as formidable as Gaspard de la Nuit. These three pieces, each unique in character and pianistic requirements, arguably represent a pinnacle of early 20th-century French piano music. This paper seeks to illuminate points for consideration for the pianist who wishes to embark upon studying the work for performance, and for the musicologist.

I shall first consider the three character poems of Aloysius Bertrand that inspired the suite, as an understanding of these Diabolic creations is essential to understanding the piece analytically and programmatically. I shall then explore the subtitle of Bertrand’s Gaspard de la Nuit: ‘Fantaisies À La Manière De Rembrandt Et De Callot’, as an acknowledgement of these artists helps us better to engage with Bertrand’s poetry, and provides us with a direct link to the visual stimuli for Ravel’s compositions.

Finally, using Ondine as a case study, I shall explore how the composer unifies his inspirations to paint a musical portrait of both the character and the content of Bertrand’s poem. I shall focus on three particular aspects of Ravel’s style: the refined textures that create washes of watery colour, subtle rhythmic variations that imply the ‘deep, rolling currents of the sleeping lake’, and the simple melodic lines sung by the water nymph in the manner of a French air. Each element plays its part in the thematic development that illustrates Ondine’s seductive powers.