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This paper presents the results of an extensive experimental investigation concerning size effects on surface generation by ball nose and flat end micro milling hardened tool steel. Cutting parameters were selected on the basis of a modular description of the uncut chip geometry. A theoretical model of the generated surfaces was used as a reference and compared with measurement results and visual inspection using an SEM. Two main effects have been observed on the tool-work material interaction at micro scale. These are responsible for the limited reduction of the roughness amplitude parameters with tool diameter and occur when the cutting edge radius to uncut chip thickness ratio becomes critical.

Eco-friendly packaging such as moulded pulp products have gained commercial importance in the recent years. However, it remains a greatly under-researched area, and there is an arising need to consolidate the best practices from research and industry in order to increase its implementation. The goal of this paper is to give an overview of the main aspects involved in the manufacture of moulded pulp products. This includes a classification of moulded pulp products, historical and current applications, production processes, materials, mechanical properties and environmental sustainability. Moreover, based on the latest research in the field, an innovative drying technique that utilizes concepts derived from impulse drying is presented, and the implementation of this process technology is discussed. Copyright © 2017 John Wiley & Sons, Ltd. INTRODUCTIONMoulded pulp products, also referred to as moulded pulp or moulded fibre products, are primarily used for the packaging of manufactured products and for food-related carriers, such as food containers and serving trays. Because of form (geometry) and aesthetic limitations, moulded pulp products have mostly been limited to the egg tray market for many years. However, demand is now increasing because of their sustainable qualities.1 Environmental, social and economic concerns result in a growing search for more sustainable products and industrial processes. As it consists simply of water and wood fibres (i.e. primarily cellulose), moulded pulp is a renewable material and a biodegradable solution. The manufacturing process includes the recovery of discarded materials from manufactured and recycled products made of wood fibres, such as cardboard, newspapers and magazines. These qualities have enabled growing adoption within the packaging industry. Companies are eager to embrace alternatives to oil-based forms of packaging, because of government regulations and customer demands. Increasing R&D effort for standardizing design and testing practices is essential in order to meet the growing demand for eco-packaging with high-quality features.Reviews of the historical development in industrial applications of moulded pulp packaging, recent manufacturing innovations in the field and an overview of an industrial scenario in the UK are 5 While these articles give great insight into historical developments, they are outdated, and they report few of the recent innovations within the field. Consequently, not enough attention has been given to the different manufacturing processes, and there is a gap related to environmental considerations. By means of a comprehensive review, this paper fills the identified research gap by describing wide-ranging aspects of the manufacturing process of moulded pulp. The research method adopted in collecting and reviewing the publications focused the literature survey exclusively to moulded pulp. It excluded similar products used in the packaging industry, such as cardboard or honeycomb panels.The content has been organized to present the main aspects ...

We report results of extensive experimental and numerical studies of the anisotropy of water drops deposited on single rectangular posts of mesoscopic size sculpted on different materials. Drops of different volume deposited on the top face of the posts assume an elongated shape along the post direction. Systematic investigations show that while the angle measured along the direction parallel to the post does not change, the one measured across them increases monotonically with the drop volume. The difference in these two angles is found to be proportional to the contact line eccentricity even for very elongated drops, regardless of the post size and material. Results obtained with the lattice Boltzmann method are consistent with these observations and indicate useful trends on the evolution of the drop shape with the system main parameters. We argue that drops deposited on single posts having a very sharp profile represent an ideal model system to investigate anisotropic wetting.

We report results of extensive experimental and numerical studies on the suspension of water drops deposited on cylindrical pillars having circular and square cross sections and different wettabilities. In the case of circular pillars, the drop contact line is pinned to the whole edge contour until the drop collapses due to the action of gravity. In contrast, on square pillars, the drops are suspended on the four corners and spilling along the vertical walls is observed. We have also studied the ability of the two geometries to sustain drops and found that if we compare pillars with the same characteristic size, the square is more efficient in pinning large volumes, while if we normalize the volumes to pillar areas, the opposite is true.

We report a study of the correlation between three optical methods for characterizing surface roughness: a laboratory scatterometer measuring the bi-directional reflection distribution function (BRDF instrument), a simple commercial scatterometer (rBRDF instrument), and a confocal optical profiler. For each instrument, the effective range of spatial surface wavelengths is determined, and the common bandwidth used when comparing the evaluated roughness parameters. The compared roughness parameters are: the root-mean-square (RMS) profile deviation (Rq), the RMS profile slope (Rdq), and the variance of the scattering angle distribution (Aq). The twenty-two investigated samples were manufactured with several methods in order to obtain a suitable diversity of roughness patterns. Our study shows a one-to-one correlation of both the Rq and the Rdq roughness values when obtained with the BRDF and the confocal instruments, if the common bandwidth is applied. Likewise, a correlation is observed when determining the Aq value with the BRDF and the rBRDF instruments. Furthermore, we show that it is possible to determine the Rq value from the Aq value, by applying a simple transfer function derived from the instrument comparisons. The presented method is validated for surfaces with predominantly 1D roughness, i.e. consisting of parallel grooves of various periods, and a reflectance similar to stainless steel. The Rq values are predicted with an accuracy of 38% at the 95% confidence interval.