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The purpose of this study is to investigate the microstructural evolution of high-strength 2024 Al alloy prepared by the laser powder bed fusion (L-PBF) additive manufacturing (AM) route. The high-strength wrought Al alloy has typically been unsuitable for AM due to its particular solidification characteristics such as hot cracking, porosity and columnar grain growth.

In this research work, samples were fabricated using L-PBF under various laser energy densities by varying laser power and scan speed. The microstructural features that developed during the solidification are correlated with operating laser parameters. In addition, finite element modelling (FEM) was performed to understand the experimentally observed results.

Microstructure evolution and defect formation have been assessed, quantified and correlated with operating laser parameters. Thermal behaviour of samples was predicted using FEM to support experimental observations. An optimised combination of intermediate laser power and scan speed produced the least defects. Higher energy density increased hot tearing along the columnar grain boundaries, while lower energy density promoted void formation. From the quantitative results, it is evident that with increasing energy density, both the top surface and side wall roughness initially reduced till a minimum and then increased. Hardness and compressive strength were found to decrease with increasing power density due to stress relaxation from hot tearing.

This research work examined how L-PBF processing conditions influence the microstructure, defects, surface roughness and mechanical properties. The results indicates that complete elimination of solidification cracks can be only achieved by combining process optimisation and possible grain refining strategies.

This study aims to investigate the demoulding characteristics of material-jetted rapid mould inserts having different surface textures for micro-injection moulding using in-line measurements and surface metrology.

Material-jetted inserts with the negative cavity of a circular test product were fabricated using different surface finishes and printing configurations, including glossy, matte and vertical settings. In-line measurements included the recording of demoulding forces at 10 kHz, which was necessary to capture the highly-dynamic characteristics. A robust data processing algorithm was used to extract reliable demoulding energies per moulding run. Thermal imaging captured surface temperatures on the inserts after demoulding. Off-line measurements, including focus variation microscopy and scanning electron microscopy, compared surface textures after a total of 60 moulding runs.

A framework for capturing demoulding energies from material-jetted rapid tools was demonstrated and compared to the literature. Glossy surfaces resulted in significantly reduced demoulding forces compared to the industry standard steel moulds in the literature and their material-jetted counterparts. Minimal changes in the surface textures of the material-jetted inserts were found, which could potentially permit their prolonged usage. Significant correlations between surface temperatures and demoulding energies were demonstrated.

The research presented here addresses the very topical issue of demoulding characteristics of soft, rapid tools, which affect the quality of prototyped products and tool durability. This was done using state-of-the-art, high-speed sensing technologies in conjunction with surface metrology and their durability for the first time in the literature.

The purpose of this study is to demonstrate and characterise a soft-tooled micro-injection moulding process through in-line measurements and surface metrology using a data-intensive approach.

A soft tool for a demonstrator product that mimics the main features of miniature components in medical devices and microsystem components has been designed and fabricated using material jetting technique. The soft tool was then integrated into a mould assembly on the micro-injection moulding machine, and mouldings were made. Sensor and data acquisition devices including thermal imaging and injection pressure sensing have been set up to collect data for each of the prototypes. Off-line dimensional characterisation of the parts and the soft tool have also been carried out to quantify the prototype quality and dimensional changes on the soft tool after the manufacturing cycles.

The data collection and analysis methods presented here enable the evaluation of the quality of the moulded parts in real-time from in-line measurements. Importantly, it is demonstrated that soft-tool surface temperature difference values can be used as reliable indicators for moulding quality. Reduction in the total volume of the soft-tool moulding cavity was detected and quantified up to 100 cycles. Data collected from in-line monitoring was also used for filling assessment of the soft-tool moulding cavity, providing about 90% accuracy in filling prediction with relatively modest sensors and monitoring technologies.

This work presents a data-intensive approach for the characterisation of soft-tooled micro-injection moulding processes for the first time. The overall results of this study show that the product-focussed data-rich approach presented here proved to be an essential and useful way of exploiting additive manufacturing technologies for soft-tooled rapid prototyping and new product introduction.

The aim of this study is to demonstrate the benefit of design flexibility afforded by the Arcam free‐form fabrication process in the direct manufacture of injection mould inserts with complex cooling channel configurations and the process efficiency and quality gains achieved through using such inserts.

The manufacturing process of a flood cooled injection mould insert using the Arcam EBM S12 layered manufacturing process is presented. The insert is then evaluated against two other inserts (one un‐cooled and one traditionally baffle cooled (BC)) in the manufacture of test components, with the temperature of the insert and components recorded. The process conditions were adjusted (reduced cooling time) to increase the core and component temperatures to identify the operational limits of the inserts. Thermal imaging was employed to visualize the thermal distribution within the BC and flood cooled (FC) inserts.

The cooling efficiency of the FC insert was found to be significantly higher than that of the other two inserts, and the homogeneity of the heat distribution of the FC insert was more even than the BC insert. It was possible to manufacture non‐deformed components using the FC insert with zero cooling time (ejection immediately after removal of holding pressure), this was not possible with the BC insert.

Provides a basis for the development of more efficient and thermally homogeneous inserts through the Arcam EBM process.

Provides a technology/process for the manufacture of highly efficient core inserts for injection moulding, offering the industry a competitive advantage through the potential for time and cost savings and higher quality components.

This is the first direct comparison of an Arcam EBM manufactured insert with complex cooling geometries against traditionally cooled inserts, particularly novel is the thermal imaging analysis of the cooling efficiency and distribution.

While international learning programs have received a great deal of attention and have been found to provide valuable learning experiences for participants interested in developing global leadership competencies (GLCs), they are resource-intensive and variably effective. This chapter examines the relatively unexplored use of assessment center (AC) methodology as a complementary avenue for developing students’ GLCs. Scholarly literature sources pertaining to GLCs and their development, experiential learning theory, and AC methodology are reviewed to develop a conceptual model and propositions related to participants’ learning in an AC designed to develop GLCs. An example is described of one university’s design and facilitation of an AC used to develop students’ GLCs. The role of AC methodology, along with international and other learning experiences for developing students’ GLCs, and recommendations for future research, are discussed.

This chapter demonstrates how the reception, adaption and development of gender studies in Brazil and subsequent law reform have created a new theoretical field of feminist criminology with a Southern approach. During the 1980s, Brazilian literature discussed gender violence according to three theories: male domination (Chauí), patriarchal domination (Saffioti) and relational violence (Gregori). Gender theories were introduced and developed during the 1990s. Decolonial studies stressed the deeper intersection of gender with race, social class and other vectors of discrimination, which increases the vulnerability of minority women, particularly black and indigenous women. The increase in gender studies supported political feminist advocacy to promote law reform, such as the Maria da Penha Law, the criminalisation of femicide, reforms related to sexual violence and women in prison. Feminist criminology has both criticised law and used it to promote gender equality on society. Judicial practices indicate the conservative resistance of the juridical field to assimilating gender debates and feminist critical theories as a whole.

OWING to the comparatively early date in the year of the Library Association Conference, this number of THE LIBRARY WORLD is published so that it may be in the hands of our readers before it begins. The official programme is not in the hands of members at the time we write, but the circumstances are such this year that delay has been inevitable. We have dwelt already on the good fortune we enjoy in going to the beautiful West‐Country Spa. At this time of year it is at its best, and, if the weather is more genial than this weather‐chequered year gives us reason to expect, the Conference should be memorable on that account alone. The Conference has always been the focus of library friendships, and this idea, now that the Association is so large, should be developed. To be a member is to be one of a freemasonry of librarians, pledged to help and forward the work of one another. It is not in the conference rooms alone, where we listen, not always completely awake, to papers not always eloquent or cleverly read, that we gain most, although no one would discount these; it is in the hotels and boarding houses and restaurants, over dinner tables and in the easy chairs of the lounges, that we draw out really useful business information. In short, shop is the subject‐matter of conference conversation, and only misanthropic curmudgeons think otherwise.

Prior to widespread social insurance, European governments experimented with a variety of programs to protect workers from income loss due to illness. This paper examines the consequences for worker absenteeism of making sickness insurance coverage voluntary or compulsory. Medical benefits appear to have reduced absenteeism for all workers. The effect of paid sick leave depended on insurance fund membership status. Better-paid workers found it easier to take time off in compulsory than in voluntary funds. Distinctive information problems plagued voluntary systems, and eventually were resolved by rejecting the voluntary ideal and forcing all workers into a single risk pool.

The author takes a comprehensive look at the accessibility of e-resources for all people, including those with disabilities, in the context of collection development (CD).

Employing a combination of research methodologies—policy analysis, content analysis, and phone survey—the author explores the extent to which the needs of people with disabilities are considered.

Several professional library organizations recommend accessibility-sensitive selection and procurement procedures. However, not all students enrolled in library school programs might learn about the issue. Few books on the subject cover the issue adequately. Nationwide, CD policies requiring conformance to accessibility standards are the exception; and when librarians meet to make decisions about the selection of specific e-resources, the needs of people with disabilities are rarely on their radar screens.

Researchers conducting similar surveys in the future might want to not only select a statistically more representative sample of academic libraries but also widen their focus and include both accessibility and usability in their investigations.

Textbook authors and course instructors in the area of CD need to address accessibility and usability. Librarians need to raise the issue with database and e-book vendors during license negotiations.

The acquisition of e-resources designed to be accessible and usable for all will enable people with disabilities to participate more fully in our information-driven society.

The data collected provide for a broad discussion of the extent to which the needs of people with disabilities are considered in connection with CD.

This work was performed within IMI Spray Mould, an EPSRC joint funded programme, aimed at developing a manufacturing route for large aerospace composite forming tooling, based on metal spray technologies. Assesses the mechanical properties of Invar steel coatings, deposited using electric arc spraying, and correlates these properties to the spray parameters and processes used so as to offer coatings with characteristics appropriate to the tooling requirements. In particular, two processing methods, inert and air atomisation, and three arc spray gun configurations (air cap design) are evaluated. The mechanical properties of the coatings are found to be low compared to bulk Invar, regardless of the spray parameters and hardware used. Inert arc spraying affords more consistent coating characteristics but this comes with a compromised durability. The spray hardware is found to be more significant in determining the coating properties than the parameters employed.