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Thermoplastic fibre metal laminates (FMLs) increasingly attract attention in manufacturing parts that must present high strength-to-weight and stiffness-to-weight ratios. In addition, their polymer matrix's recyclability meets sustainability needs that conventional thermosetting-based FMLs cannot encounter. Mechanical drilling is one of the most used manufacturing operations they are subjected to, but it can still be a source of damage in the drilled zone, which, in turn, can impair the part service performance. In particular, the interface conditions between the metal skins and composite core significantly determine the drilling performance. In this framework, the paper investigates how the metal sheet surface modification treatments and composite polymer matrix characteristics can affect the drilling operation performance. It has been proved that rough metal surfaces and a polymer matrix with enhanced thermal resistance are the best combinations to ensure the integrity and quality of drilled holes. [ABSTRACT FROM AUTHOR]

This paper explores the feasibility of adopting additive manufacturing followed by heat treatment and finish machining to fabricate Nitinol components with enhanced surface integrity and more favourable superelastic characteristics. The most suitable manufacturing approach is demonstrated to achieve these characteristics by establishing appropriate bulk and surface conditioning. New insights are presented on the correlation of process chain parameters and Nitinol superelastic response focusing on the role of the microstructural constituents and surface integrity generated from finish machining with different cooling conditions. The wear behaviour of Nitinol components fabricated by the proposed manufacturing approach is also evaluated to demonstrate bearing applications. [ABSTRACT FROM AUTHOR]

This paper takes the broad topic of geometrical surface imperfections on manufactured surfaces and provides an overview of how they affect component functionality and how they may be detected and classified as defects or not. The presented overview considers both human visual inspection and machine vision-based approaches along with their evolving roles. Of note is that the paper takes a highly granular field consisting of customized solutions for customized applications and frames the discussion around fundamental considerations for each of the tasks; search/acquisition, sensing/detection, processing, classification and decision. Future trends and areas still requiring attention are highlighted. [ABSTRACT FROM AUTHOR]

The request for more resistant but still light components has focused the manufacturing industry's interest in composite materials. The manufacturing of parts made of composite may require drilling operations; nevertheless, assuring a good hole quality still represents a challenge for these materials. The present work provides, for the first time, a comparison between different drilling technologies, namely ultrasonic drilling and cryogenic drilling, proposing them as alternatives to dry drilling. After drilling, the hole surface quality is characterized in terms of geometrical accuracy and delamination. Results show that innovative cutting methods can significantly improve the drilling performances within a well-defined process parameters window. [ABSTRACT FROM AUTHOR]

On-machine and in-process surface metrology are important for quality control in manufacturing of precision surfaces. The classifications, requirements and tasks of on-machine and in-process surface metrology are addressed. The state-of-the-art on-machine and in-process measurement systems and sensor technologies are presented. Error separation algorithms for removing machine tool errors, which is specially required in on-machine and in-process surface metrology, are overviewed, followed by a discussion on calibration and traceability. Advanced techniques on sampling strategies, measurement systems-machine tools interface, data flow and analysis as well as feedbacks for compensation manufacturing are then demonstrated. Future challenges and developing trends are also discussed. [ABSTRACT FROM AUTHOR]

Additive Manufacturing (AM) techniques are more and more employed in the biomedical industry to produce surgical implants made of Ti6Al4 V alloy. After the AM process, some finishing machining operations are still required to obtain the final product geometry. In recent years, cryogenic cooling has been adopted to improve the Ti6Al4 V poor machinability, but mainly in rough machining operations. This paper investigates the feasibility of cryogenic cooling when finishing turning AM acetabular cups made of Electron Beam Melted (EBM) Ti6Al4 V, focusing on the obtainable surface integrity and geometrical quality, compared to dry cutting. Experimental outcomes highlight that cryogenic cooling is feasible for short turning lengths to limit tool holder contractions. [ABSTRACT FROM AUTHOR]

Geometrical distortions due to inappropriate setting of process parameters are one of the main causes of variability in manufacturing hot forged thin parts. Their identification and measurement at the earliest steps of the process chain may permit significant benefit especially in case of small batch production. The paper presents a coordinate measuring system for fast inspection of freeform parts at elevated temperatures through high-speed laser triangulation. Main error sources are discussed, including a new method for the correction of systematic errors due to imperfect laser planes alignment. A procedure for testing the metrological performances at elevated temperature is also presented. [ABSTRACT FROM AUTHOR]

Abstract: Micro injection molding is a key technology for mass-production of micro-structured surfaces, such as optical and microfluidic devices. However, the complete replication of high aspect ratio micro features is challenging even using state-of-the-art high-speed injection systems, rapid heat cycle molding and vacuum mold venting. In this work the technological limits of micro-injection molding in replicating high aspect ratio micro-structured surfaces are experimentally investigated, using the molding of a bio-MEMS for erythrocytes depletion as a case study. The obtained results show how these limits are inherently related to an uneven distribution of cavity pressure during mold filling. [Copyright &y& Elsevier]

Abstract: One of the factors contributing to limited reproducibility of coordinate measurements is the use of different inspection software. Time-consuming efforts for translation of part programmes are sometimes needed, and interoperability of inspection equipment has the potential to reduce these inefficiencies. The paper presents a methodology for an economic evaluation of interoperability benefits with respect to the verification of geometrical product specifications. It requires input data from testing and inspection activities, as well as information on training of personnel and licensing of software. The model is illustrated using an automotive case study and the related assessment of an investment in interoperability. [Copyright &y& Elsevier]

Abstract: Accurate quantification of volume is important in many different applications, including calibration of containers for fluids, wear evaluation, and inspection of cavities and medical dispensing devices. Volume assessment methods based on dimensional measurements have the potential to be more accurate than gravimetric ones. This paper proposes and compares different methods for obtaining traceable volume measurements, based both on contact and noncontact coordinate measuring techniques, including computed tomography. The focus is on the design of measurement procedures and their applicability for users in industry. Measurement methods are validated with reference to two case studies, using calibrated reference parts. [Copyright &y& Elsevier]

Abstract: Atomic Force Acoustic Microscopy (AFAM) is a scanning probe technique for advanced research in nanomechanical properties, using local elasticity to provide direct and non-destructive mapping of Young''s modulus and related surface parameters. In this work, an experimental study is presented, addressing the performance of quantitative AFAM characterization. Different influencing factors are analysed, mainly arising from probe characteristics (such as cantilever geometry, force constant and ultimately resonance frequency) and scan settings (speed and sample vibration frequency). Investigations encompassed a commercial instrument equipped with three different probes, featuring different dimensions and mechanical properties. [Copyright &y& Elsevier]

Abstract: An increasing number of manufactured parts are measured in industry using non-contact measuring systems. The paper describes an industrial comparison of coordinate measuring machines (CMMs) equipped with optical sensors, performed in Europe from August 2007 to January 2009 involving 21 optical CMMs. Participants, mainly small–medium size industrial companies, were asked to measure a set of calibrated artefacts with measurement tasks of different complexity. They include both 1D/2D standards (glass scale and optomechanical hole plate) and 3D injection moulded workpieces of different colours (four plastic Lego bricks). In addition to the evaluation of actual metrological performances of optical CMMs in industry, an important aim of the comparison was to investigate the validity of measurement uncertainty statements provided by participants. The focus of this investigation was on the additional error sources that emerge when using optical CMMs. Results demonstrate that: (i) the interactions of optical sensors with material and surface of parts are among the most important error sources; (ii) the users of optical CMMs in most cases are not aware of the magnitude of these effects; (iii) specific uncertainty evaluation procedures, suitable for industrial users of optical coordinate measurements, are needed. [Copyright &y& Elsevier]

Abstract: The paper presents a new concept of micro-artefact, the fiber gauge, consisting of a set of optical fibers sticking out from a flat surface. The fibers are arranged as a regular array of different height cylinders, with aspect ratios up to 20:1. The artefact is produced taking advantage of optical fibers manufacturing technology, featuring relatively high geometrical accuracy, combined with very good mechanical properties. The fiber gauge can be applied to calibration of most contact or non-contact instruments for characterization of surface topographies and 3D micro-geometries, such as micro- or nano-CMMs, optical instruments, etc. Different designs and dimensions allow for realization of structures that can be adapted to various instruments calibration needs. Development, analysis and application of prototype artefacts are reported. [Copyright &y& Elsevier]

Abstract: The scope of this keynote paper is to present the state of the art in the metrology of freeform shapes with focus on the freeform capabilities of the most important measuring techniques and on related metrological issues. Some examples of products are presented, for which the metrology of freeform shapes is important to guarantee the desired functional performance of the product. A classification of freeform measuring tasks and the corresponding metrological requirements are presented. A review of the most important measuring techniques is presented along with their capabilities for freeform measuring tasks. Specification and verification of freeform surfaces, including data evaluation and comparison to specifications are discussed, along with the measurement uncertainty and traceability of freeform measurements. [Copyright &y& Elsevier]

Abstract: In this paper a new measurement approach is presented; the probe is driven over the sample surface according to a feature-oriented measurement strategy, in order to scan with high resolution just the discrete features of interest. Such intelligent tip motion is made possible by re-programming of the actuation system through a software interface with the instrument control. This new approach optimizes the measurement operations, enabling the selection of higher resolutions where needed and allowing for considerable measurement time reduction. Furthermore, minimisation of the total scanned length allows a reduction of tip wear. The proposed method was tested on the characterization of complex microstructures. Results are discussed in terms of advantages and limitations in comparison to traditional raster scanning measurements. [Copyright &y& Elsevier]

Abstract: Performance verification of Coordinate Measuring Machines (CMMs) is a key task in quality assurance systems. Test results are influenced by various error sources that affect the test with their uncertainty contribution, therefore the correct identification and quantification of these error sources is a crucial task for a proper estimation of the test uncertainty. The paper discusses the identification of the uncertainty contributions to be taken into account for the estimation of the test uncertainty in connection to three tests for the verification of important CMM subsystems: i) rotary table test; ii) contact scanning probe test; iii) video probe test. [Copyright &y& Elsevier]