International Journal of Lightweight Materials and Manufacture最新文献

The results of modeling and research of casting, rolling, and extrusion processes for producing wire from Al–Zr system alloys and determining its physical and mechanical properties have been presented. When implementing combined processes for processing aluminum alloys, the number of operations is significantly reduced, productivity and yield are increased.

As a result of the conducted research, the influence of alloy preparation modes and their chemical composition on the physical, mechanical and electrical properties of longish semifinished products from Al–Zr system alloys obtained by combined rolling-extrusion (CRE) and ingotless rolling-extrusion (IRE) methods were investigated.

The simulation of the CRE process for one of these alloys of the system was carried out in the DEFORM 3D software package using data on its rheological properties obtained by the hot torsion method. Based on the modeling results, the optimal modes for conducting experimental studies were selected.

The features of metal forming were experimentally studied, the temperature-velocity and technological parameters of combined processing were found, as well as the properties of cast billets, including those obtained using an electromagnetic mold (EMM). The results of experimental studies of the CRE and IRE processes suggest that it is possible to obtain longish deformed semifinished products from alloys Al–Zr system with a level of physical, mechanical and electrical properties that meet international standards.

At all technological stages, including drawing, the structure of the metal was studied, and data on the physical and mechanical properties of hot-extruded rods and wire in cold-deformed and annealed states was obtained.

The heat resistance of wire made from the investigated alloys was studied and it was found that after testing at a temperature of 280 °C and a holding time of 1 h, it satisfies the requirements of the AT3 type standard with a maximum permissible long-term operating temperature of 210 °C.

Recommendations are given for industrial implementation; alloys containing 0.15–0.20% zirconium and 0.10–0.15% iron are recommended for the manufacture of AT1 type wire without heat treatment, as well as 0.25–0.30% Zr and 0.2–0.25% Fe for AT3 wire type with heat treatment.

Production techniques used in processing alloy and composite materials have the propensity of improving their properties or deteriorating them. Therefore, appropriate choice of processing routes is a prerequisite for the development of top-notch high entropy alloys (HEAs). The types and forms of phase(s) developed in HEAs are also influenced by the processing technique. Incidentally, their properties are influenced by the phases present. So, the aim of this study was to investigate the characteristics of phases present in HEAs, and how they affect their properties and applications. More so, to investigate the processing techniques used in the development of HEAs and their influence on their properties and applications. The resource materials were sourced from Scopus database and google scholar website of articles published in the last ten years, laying more emphasis on the most recently published works. In the study, it was discovered that formation of the phases was dependent on: was dependent on: the type of the production process, present elements and the employed processing parameters. Hence, it was concluded that optimization of processing parameters and careful selection of elements are the key factors to develop HEAs of reputable properties.

A study was carried out to investigate and enhance the effects of friction stir welding on the mechanical characteristics of a flange composed of 6061-T3 aluminum alloy. The pipes possess an outer diameter and wall thickness of 6 mm, while the plates are sized at 100 x 100 × 6 mm. Nine unique experiments were planned using the Taguchi orthogonal array method, with the welding tool remaining constant. Three independent variables (travel speed, rotation speed, and shoulder diameter) were altered at three different levels for each variable. The research analyzed the influence of various FSW factors on the weld flange joint. Analysis of variance (ANOVA) and grey relational analysis (GRA) were employed to determine the impact of each FSW underwater parameter. Moreover, the statistical Taguchi technique (TM) was used to predict the optimal combination of welding parameters to improve tensile properties, including tensile strength (UTS), yield strength (YS), elongation (EI%), and bending load (BL) of welded joints. Additionally, the actual tests demonstrated a high level of agreement with the results obtained from the proposed mathematical model. The validation results obtained indicate that the optimization method is a dependable tool for enhancing the quality responses of friction stir welding.

A novel approach to enhancing the efficacy and surface quality of magnetic polishing involves the incorporation of a magnetic liquid circulation system for abrasive particle regeneration in conjunction with a circular Halbach array. The continuous renewal of abrasive particles within the polishing zone is realised through a conveyor belt that transports new abrasive particles into the polishing liquid solution. This formation of a continuously circulating polishing system ensures uninterrupted magnetic finishing processes and maintains stability throughout the polishing operation. This study extensively explores polishing force distribution, magnetic field distribution and abrasive grain behaviour in the polishing area facilitated by the magnetic liquid solution. The application of the proposed polishing processes to polymethyl methacrylate, an optical lens material, aims to comprehend the characteristics and validate the feasibility of the polishing method. Key influencing factors in the magnetic polishing process, including abrasive grain size, magnetic particle, polishing distance and conveyor speed to surface quantity, are examined through experimental analysis. Results of the experimental polishing processes demonstrate that the utilisation of circular Halbach arrays with circulating abrasives produces a nanometric surface finish. Even in the polishing of polymethyl methacrylate with an initial rough surface (Ra = 464.895 nm), the process achieves an ultra-fine level with Ra below 9 nm without disruption in the material polishing processes of optical lenses.

This paper offers a comprehensive overview of recent advancements in digital twin technology applied to additive manufacturing (AM), focusing on recent research trends, methodologies, and the integration of machine learning. By identifying emerging developments and addressing challenges, it serves as a roadmap for future research. Specifically, it examines various AM types, evolving trends, and methodologies within digital twin frameworks, highlighting the role of machine learning in enhancing AM processes. Ultimately, the paper aims to underscore the significance of digital twin technology in advancing smart manufacturing practices. A total of 133 papers were identified for analysis through IEEExplore, ScienceDirect, Web of Science, and Google Scholar and web resource. Approximately 74% of the papers are journals and 21% are conferences and proceedings. Moreover, 78% of the journal papers were Q1 journals. The paper identifies the potential benefits of digital twins at different levels, the existing problems associated with implementing digital twin in additive manufacturing, recent advancements, the existing approaches, and the framework. This review provides a comprehensive overview of the current landscape of research in digital twin technology for additive manufacturing, utilizing the latest resources to identify cutting-edge developments and methodologies. Through an exploration of potential benefits and implementation challenges, the review offers valuable insights to researchers and practitioners in the field. Additionally, it contributes to the discourse by offering a nuanced discussion on future research directions, paving the way for further advancements.

Laser peen forming (LPF) is an appealing technique for forming metal sheets using high-energy, short-duration laser pulses. The deformation of the target metal plate is closely related to the magnitude and distribution of laser-induced residual stress. Consequently, the relationship between process parameters and residual stress is worth researching. In this research, two process parameters in LPF, laser energy and coverage ratio (spot distance essentially), and one workpiece parameter, plate thickness, were examined through an element method (FEM) of multiple square-spot laser shock peening (SSLSP). Corresponding experiments of SSLSP on aluminum alloy 2024-T351 test blocks were conducted, together with an X-ray diffraction (XRD) residual stress measurement and a surface morphology observation. The FEM simulation and experimental results show that congested laser spots had a significant influence on the magnitude of compressive residual stress; higher laser energy was beneficial to the depth of the compressive stress layer but could decrease its magnitude. Therefore, for better forming ability, higher laser energy and a higher coverage ratio are beneficial; for surface strengthening, laser energy should not be too large, and the coverage ratio should be larger than 100% to ensure that the residual stress on the treated surface is compressive, resulting in better surface integrity.

There is a real demand for sustainable lightweight structures because of the growing environmental concerns. One important solution is developing structures through recycled scrap/waste thermoplastic materials. The current work studies the friction stir spot weldability of recycled thermoplastics, which will help to analyze the potential of friction stir-based welding techniques towards developing these sustainable structures. The combined behavior of recycling-welding procedures is investigated, as they may cause degradations; to ensure that the base thermoplastic polymer's chemical, thermal, and mechanical properties are retained. Scrapped milk bottles made from HDPE material are used as a case study. The highest lap-shear load of 1528 N was achieved at the optimum welding conditions of 1600 rpm rotational speed, 1 mm plunge depth, and 60 s dwell time. Fractographic studies (macroscopic and SEM-based) suggested four types of fracture morphologies depending on welding conditions used. The DSC results showed no significant differences in melting temperature and crystalline content of the polymeric material. The TGA tests showed no significant thermal degradations. The FTIR analysis of all the samples (bottle, recycled sheet, weld material) exhibited characteristic HDPE peaks. All these results suggest combined-welding recycling had a minimal impact on the polymeric structure. Thus, friction stir spot welding (FSSW) technique joins recycled thermoplastic scrap/waste materials with high lap-shear load and without any significant polymer degradations.