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Today, far too many products are scrapped due to surface related issues, products with perfect function but with minor surface blemishes. The complaints are often offset by goodwill commitments from suppliers at great cost to them and delivery delays and lead time costs for customers. The reason is that the industry relies on several non-standardized classification systems for surface quality that are based on various combinations of and designations for surface defects, assessed by visual inspections at a defined distance to determine the severity of any detected surface deviations. These similar classification systems provide far too much scope for subjective and non-repeatable assessments causing communication problems between customer and producer at all stages in the supply chain. To challenge this situation, a common toolbox to communicate, describe and define surface quality should be developed, i.e. a standardisation of surface quality assessment including various effects and defects with a jointly established nomenclature and evaluation parameters. This work presents the first step of a research project bringing together 11 suppliers and OEMs along the supply chain, from the delivery of raw aluminium to finished alumina profiles included in consumer products. The final goal of the project is to develop an ‘objective classification of visual requirements’ on alumina profiles towards increased sustainability and decreased material wastage. Presented result is a common terminology with links to the process chain, surface defect geometry and visual appearance aiming at making the communication between producers and buyers of the aluminium profiles clearer and more unambiguous when it comes to specification and requirements of profile surfaces in each of the supply-chain links. Future work will add measurable parameters specifying surface quality.

Large costs and lead-time losses are created by returned aluminum products - to a great extent unnecessarily. Much of the metal product complaints are due to visual surface defects. Today, the aluminum industry relies on several non-standardized classification systems for surface quality assessments which provides far too much scope for subjective and non-repeatable surface estimations. To challenge this situation, a common toolbox to describe and define surface quality in a more objective way needs to be developed. A first step towards such standardization is to speak the same language, thus this study is based on a state-of-the-art survey covering terminology and descriptions of surface defects in literature, and a round-robin assessment collecting terms used by employees at seven companies within the aluminum industry. The literature study showed that most attempts to catalog and categorized various types of defects on commercial aluminum extrusions are based on the origin of defects and how to prevent and/or reduce them, thus the vocabulary is production-oriented and most terms are not useful from the customers' nor the designers' point of view when coming to describe desired surface effect, i.e. perceived surface quality. The round-robin assessment confirmed the large variation of terminology used, and that defects were judged differently also within the same company due to experience and field of work. A common vocabulary is suggested to be based on the relationships between used expressions; from general terms at stages linked to consumers, designers and sale, tracing towards more technical terms the closer the stage where the origin of the defect can be found. This structure, in combination with e.g. manufacturing cost, is expected to guide customers towards more sustainable surface quality choices that, together with more consistent surface assessments along the production chain, is expected to strongly reduce unnecessary scrapping.

The manufacturing and finishing (honing) of cylinder liners for the automotive industry is a constant challenge in order to reduce friction losses and oil consumption. A better knowledge of surfaces generated during plateau honing is then required for optimization of the process. Despite a well-known and controlled honing process, variations in surface roughness appear due to honing tool wear and need to be mapped and analyzed. The following paper proposes to map the variations in roughness by using confocal 3D measuring equipment able to inspect any area of a cylinder liner. Six motor blocks, each with five cylinder liners, were evaluated with 20 topography measurements per liner (giving six hundred 3D measurements in total). In addition to standard 3D roughness parameters, tailor made parameters extracting honing texture information are computed. The results show that only a few parameters (Spk, Ssc and Sk) do correlate with the honing tool wear specific to each cylinder. Tailor made parameters indicate similar results. Indeed, as the honing tool wears down, the cylinder liner surface gets rougher plateau or peaks and sharper asperities indicating that ploughing occurs instead of cutting. In future, experimental models could be built in order to perform production and functional optimizations. © 2015 Elsevier Inc. All rights reserved., The authors wish to thank NanoFocus AG and T. Hoering, Volvo Car Corporation and L. Fahlgren, F. Strömstedt, F. Falck for their financial support, their contribution in man hours and material. The authors are also thankful for the collaboration with Digital Surf through Mount Shasta program.

New surface treatments, novel material developments, and improved quality control procedures and advanced metrology instrumentation create a possibility to further develop competitiveness by the selection of “optimal” surface features to a product. The customers’ first apprehension of a product and the creation of desire is a very complex but tempting process to learn to master. The product appearance plays an important role in the judgement of a product, and the surface is, among form, colour, and material of greatest importance in creating a whole impression of a product. This work addresses this “partly possible” and “to a great extent impossible” task and is a novel approach to develop and join a traditional physical metrology frame-work with qualitative gradings of apprehended impressions and feelings of products with varying surface properties. The aim of the study is to demonstrate the metrology framework linking measurable- and un-measurable properties of product surfaces to customer feeling/experience as exemplified by a set of industrial applications. The results based on three case studies show that the usage of the "Kansei" method leads to an improved knowledge about surface features in relation to the customers’ demand as exemplified with “the sauna-“ and “the building exterior” surface cases. Clear links between the expectations of the emotions linked to the products have been associated to the design variable -surface topography. Future studies will be initiated based on the results in this work to further explore the possibilities with the tactile- and colour properties to further utilize the properties of surfaces as a strategic tool for product developers.

Funding: Swedish Programme for Production Engineering Education and Research (PROPER)