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Building a technology-driven world appears to be the main motivational force behind students choosing to undertake engineering studies. The first year of engineering education plays a significant role in demonstrating sufficient mathematical and scientific rigor to satisfy these motivational factors. The common applied mechanics courses play a central role in achieving this. At the same time, a vast majority of students suffer from a lack of the necessary mathematical skills and analytical orientation for various reasons. Due to different educational philosophies and teaching pedagogies, a lack of proper integration between mathematics and applied mechanics is common. Several efforts were made to build better curriculum, teaching, and learning systems, resulting in widely varied solutions, but most of them require drastically different implementation approaches. With sufficient rigor in teaching and assessment, the first-year applied mechanics (common) courses designed for engineering students can solve students' mathematical and motivational lapses and help bridge the gaps between pre-university and university education endeavours. This paper presents evidence supporting this argument. In particular, datasets collected from the direct experiences delivering the first-year static and dynamics courses to many students over the past decade and a half are analysed to establish the proposition.

Scalmalloy is an Al–Mg alloy with additions of Sc and Zr originally developed as a high‐strength aluminum alloy with σ0.2 ≥ 450 MPa for aerospace industry. It is now well understood that the alloy is amendable for processing by laser powder bed fusion (LPBF). However, the mechanism of formation of the equiaxed‐columnar bimodal grain structure during LPBF is not ascertained yet, fully. Herein, this gap is addressed with special focus on the distributions of critical elements such as Sc and various particles that form during LBPF. It is found that strong and weak segregation of Mg and Sc, respectively, occurs in the final solidification areas of the fine‐ and equiaxed‐grain regions. The coarser and columnar grain regions show weak segregation of Mg and no Sc segregation. A priori knowledge on the Al–Sc eutectic reaction, its dependence on cooling rates, and the well‐known thermal and solidification conditions related to the track location during LPBF is used to ascertain the mechanism of formation of the bimodal grain structure. The mechanism suggested is substantiated by the location‐dependent elemental distributions and the various particles that are observed. [ABSTRACT FROM AUTHOR]

Duplex stainless steels are well known for their high corrosion resistance, strength, and other useful characteristics, but mainly suffer from a lack of machinability. Selective laser melting, one of the additive manufacturing technologies was recently shown to be suitable for processing duplex stainless steels. However, the point-by-point consolidation of the powders and the complex thermal variations convert the biphasic ferrite plus austenite structures into predominantly ferritic structures. Ferritic stainless steels were traditionally known for better machinability. The research question, if selective laser melting route can be used first to convert duplex powders into ferritic printed forms to improve the machinability is answered here, through experimental investigations machining laser melted and wrought duplex stainless-steel specimens. Comparative assessments of the mechanisms of machining by means of metallographic and micro-hardness evaluations together with preliminary insights into torque and temperature variations proved the hypothesis that selective laser melting is a promising route to alleviate the machinability problems in duplex stainless-steel systems, while also allowing to reap all the benefits of additive manufacturing. This research not only considers a nonstandard material for laser melting but addresses the machinability limitations. [ABSTRACT FROM AUTHOR]

The advent of additive manufacturing technologies presents a number of opportunities that have the potential to greatly benefit designers, and contribute to the sustainability of products. Additive manufacturing technologies have removed many of the manufacturing restrictions that may previously have compromised a designer's ability to make the product they imagined. Products can also be extensively customized to the user thus, once again, potentially increasing their desirability, pleasure and attachment and therefore their longevity. As additive manufacturing technologies evolve, and more new materials become available, and multiple material technologies are further developed, the field of product design has the potential to greatly change. This paper examines how aspects of additive manufacturing, from a sustainable design perspective, could become a useful tool in the arsenal to bring about the sustainable design of consumer products. Keywords: Sustainable product design, Additive manufacturing, Design quality, Mass customization, 1. Introduction The past decade has seen a surge in awareness for environmental conservation and the preservation of the earth's natural resources and environment. Sustainability is rapidly emerging as an [...]

In the paper, the results obtained for the fire-retardancy of ULTEM 9085 polymer composites manufactured by the fused deposition modelling (FDM) are summarized. The effects of processing parameters of FDM such as the percentage of infill, thickness of the sample, and the number of the solid layers on either side were experimentally evaluated against fireretardancy parameters (burn length and heat release rate). Based on the results, all test samples of ULTEM 9085 were observed to have passed the test requirements specified in Federal Aviation Regulation (FAR) & EASA Certification Specifications (CS) Part 25 of Airworthiness standards for the aviation sector. The maximal burn length (approx. 80 mm) was registered for 30 % infill samples with zero solid layers on either side. Based on the results obtained it was concluded that the burn length was almost the same in all build directions. Moreover, inconsistent results were obtained for the heat release rate as a function of the thickness of the sample for different build directions. Though, certain clear effects were obtained regarding burn length as a function of infill percentage proving that fire-retardancy is the most effective at higher infill percentages. [ABSTRACT FROM AUTHOR]