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The effects of plasma intensity and powder particle size on wear and erosion resistance have been evaluated for WC-12 wt.%Co coatings deposited by Air Plasma Spraying. Coatings were deposited from micrometric and nanostructured powders. SEM and XRD characterization showed the presence of WC, W 2C, W, and an amorphous Co-rich matrix. The performance of the different coatings was compared in sliding wear tests (ball-on-disk), under dry friction conditions. Wear debris and tracks were analyzed by SEM. The debris generated during the test was found to have a great influence on the sliding properties. Wear follows a "three-body abrasive mechanism" and is dominated by coating spallation because of sub-surface cracking. In order to evaluate erosion behavior, solid particle erosion tests were conducted. Eroded coatings were analyzed by SEM, and erosion mainly occurs by a "cracking and chipping mechanism." The study shows that wear and erosion behavior is strongly affected by plasma arc intensity. © 2010 ASM International.

The effects of plasma intensity and powder particle size on wear and erosion resistance have been evaluated for WC-12 wt.%Co coatings deposited by Air Plasma Spraying. Coatings were deposited from micrometric and nanostructured powders. SEM and XRD characterization showed the presence of WC, W 2C, W, and an amorphous Co-rich matrix. The performance of the different coatings was compared in sliding wear tests (ball-on-disk), under dry friction conditions. Wear debris and tracks were analyzed by SEM. The debris generated during the test was found to have a great influence on the sliding properties. Wear follows a "three-body abrasive mechanism" and is dominated by coating spallation because of sub-surface cracking. In order to evaluate erosion behavior, solid particle erosion tests were conducted. Eroded coatings were analyzed by SEM, and erosion mainly occurs by a "cracking and chipping mechanism." The study shows that wear and erosion behavior is strongly affected by plasma arc intensity. © 2010 ASM International.

The largest single point CO2 emitter in Ireland, the Moneypoint Power Station (3.95 Mt CO2 per annum), is located in Co. Clare and geologically lies within the Clare Basin. In terms of the economics of transportation of CO2 from Moneypoint, a possible local storage site would be favoured. The study investigated a number of critical criteria with respect to potential geological storage of CO2 within the onshore portion of the Clare Basin. In a screening study of this nature, the objective is to search for subsurface reservoirs that have sufficient storage capacity, good injection properties and sufficient confining potential. These properties depend on a number of geological parameters for each of the targeted formations. Reservoir size (CO2 storage capacity) depends on, among other factors, the pore volume that is available and reservoir depth. The rate at which CO2 can be injected into the reservoir is determined by the permeability and thickness of the reservoir formation(s). Confining potential depends on the seal rock type, thickness, the presence of faults and the type of trap structures. Other geological properties that are relevant for aquifer size, injectivity and seal quality also need to be considered in site characterisation studies. This study examined these key parameters using a modular approach. Extensive data collection was followed by several interpretational programmes including a detailed re-logging programme of deep historical boreholes to maximise the sub-surface data available to the project. The resultant datasets were assimilated into a Petrel geological model for the area. Two boreholes were completed at key sites within the Clare Basin. A primary objective of the drilling programme was to provide fresh material for porosity/permeability test work. Results from the rock characterisation studies were integrated into the geological model. This allowed a final assessment of the potential storage volume and suitability, revealing that the onshor

In this study, a regional scale gravity data set has been inverted to infer the structure (topography) of the top of the basement underlying sub-horizontal strata. We apply our method to this real data set for further proof of concept, validation and benchmarking against results from an earlier forward modelling done elsewhere.Our aim is to carry out implicit structural inversion, i.e., to obtain a geologically reasonable model, without specifically solving for structure. The 2.5D volume of interest is parametrized with homogeneous horizontal prisms and a two-lithology medium is assumed. A possible regional linear trend and a general floating reference are also inverted for. Using a gridded parametrization, linear programming is used to minimize the L1-norm of the data misfit, relative to a floating reference.Given a known density contrast between the lithologies, an inversion using linear programming has the intrinsic advantage that a relatively sharp image of the sub-surface is retrieved instead of a smooth one. The model recovered is almost bi-modal and its general features seem to be robust with respect to several parametrization scenarios investigated. The floating reference and a linear trend in the data were also retrieved simultaneously. The inversion results, indicating two depressions in the basement, are robust and agree with those obtained earlier based upon detailed 2D forward modelling using many narrow, near-vertical prisms. © 2010 European Association of Geoscientists & Engineers.