High Strength Lightweight Research Articles

Nanotechnology-Enabled Innovations in High-Strength Lightweight Vehicle Design for Enhanced Safety and Energy Efficiency

Global warming and resource depletion are two of the most pressing issues confronting modern society, with the automotive industry being a significant contributor to energy consumption and environmental impact. Additionally, rising fatalities from traffic accidents have highlighted the need for improved vehicle safety. This paper explores the transformative role of nanotechnology in developing high-strength, lightweight materials that enhance both vehicle safety and fuel efficiency. By incorporating nanocomposites, known for their low density, superior strength, heat resistance, and scratch resilience, vehicles can achieve significant weight reductions without compromising performance. These advancements reduce vehicle failure rates, increase passenger survival in accidents, and contribute to energy savings, whether in electric or internal combustion engine vehicles. The paper also discusses the potential of lightweight vehicles in reducing fuel consumption and carbon emissions, making them key players in combating climate change and addressing resource shortages. Through a comprehensive analysis of nanotechnology’s impact on material science, this study highlights its critical role in shaping the future of sustainable vehicle design.

Light-weight high strength porous thermal insulation materials based on dolomite-granite waste

The first choice for the treatment of solid waste is its industrial utilization. Therefore, in the present study, dolomite tailings and granite waste are used as the basic raw materials, along with silicon carbide as a high-temperature foaming agent, to prepare a light-weight, high-closed porosity thermal insulation material. The effects of (i) the chemical compositions of the main raw materials and (ii) the relationship between the sintering process and the properties, microstructure and crystalline phase of the samples are systematically investigated. At the same time, the formation mechanism of high closed porosity of the thermal insulation material is analyzed. The results showed that when sintering temperature, time, and heating rate are 1200 °C, 30 min, and 3 °C/min, respectly, the sample density, compressive strength, true porosity, and closed porosity are 0.7 g/cm3, 6.62 MPa, 74.21%, and 66.36%, respectively. In addition, due to the high closed porosity, relative to traditional inorganic thermal insulation materials, the water absorption and thermal conductivity are significantly reduced to as little as 1.5%, and 0.30 W/(m·K), respectly. This research not only realizes the recovery and utilization of granite waste and dolomite tailings, but also provides a new prospect for energy saving and consumption reduction in the construction industry.

Development of a high-strength lightweight geopolymer concrete for structural and thermal insulation applications

Investigating the thermal insulation properties of lightweight geopolymer concrete is essential. This paper aims to develop a lightweight aggregate geopolymer concrete (LWAGC) with good density, compressive mechanical and thermal insulation properties. The dry density of LWAGC was adjusted by incorporating expanded perlite (EP). The variation in physical and mechanical properties of LWAGC with different EP content was discussed, including dry density, P-wave velocity, ultimate compression strength and elastic modulus. Based on infrared thermal imaging technology, a rapid measurement method was proposed to simulate the indoor temperature change of buildings at high ambient temperatures. The thermal insulation performance of the LWAGC with different EP contents was further evaluated. The findings show that as the EP content in LWAGC increases, there is a corresponding decrease in P-wave velocity, dry density, ultimate compressive stress, and elastic modulus. The lowest dry density of LWAGC reaches 1209kg/m3 while the ultimate compressive stress is still larger than 25.0MPa, which can used as LC25 building materials in load-bearing structures. The results also show that the addition of EP can improve the thermal insulation properties of LWAGC. The LWAGC with 50% EP content has the highest reduction rate of temperature and can maintain the indoor temperature lower than 35 °C under high ambient temperature, which have potential application prospects in the load-bearing structures and thermal insulation of tall buildings.

Experimental study on the shear behaviour of high-strength lightweight concrete beams incorporating graphene oxide

Graphene oxide (GO) has achieved significant progress in the material behaviour of cement-based materials. However, research on its structural behaviour in high-strength lightweight concrete (HSLWC) structures is limited, which restricts its engineering applications. This study focused on investigating the effects of low contents of GO on the shear behaviour of HSLWC beams. A total of four HSLWC beams with GO contents of 0, 0.01, 0.03 and 0.05% (by weight of cement) were designed to observe failure modes, load‒deformation curves, shear capacities, crack behaviour and load‒strain curves under four-point loading by a 300 kN servo loading device. The results revealed that all the beams exhibited shear compression failure. GO improved the shear capacity of the HSLWC beams, and this strengthening effect increased with increase in GO content. When the content of GO was 0.05%, the ultimate load of the beam reached a maximum, which was 39.2% greater than that of the control beam. GO can endow the HSLWC beams with a certain degree of ductility. In addition, a modified JGJ 12-2006 model was proposed to predict the shear capacity of HSLWC beams containing different GO contents on the basis of a comparison of typical models. This study can provide exploratory engineering practice for evaluating and designing GO-reinforced HSLWC structures.

Development of high strength light weight concrete for RC beams by using optimum replacement level of pumice aggregate

Development of high strength light weight concrete for RC beams by using optimum replacement level of pumice aggregate

Numerical simulation of post fire-behaviour of high strength lightweight reinforced concrete beams strengthened with basalt fiber-reinforced polymer grid and engineered cementitious composites jacket

Numerical simulation of post fire-behaviour of high strength lightweight reinforced concrete beams strengthened with basalt fiber-reinforced polymer grid and engineered cementitious composites jacket

Composition driven machine learning for unearthing high-strength lightweight multi-principal element alloys

High-strength, lightweight alloys are highly desired in the aerospace, automotive and marine industries. The optimization of such alloys is a multifaceted process, characterized by the consideration of diverse objectives and constraints. Various optimization methodologies exist, spanning from intricate first-principle approaches to the application of sophisticated machine learning algorithms. These algorithms might incorporate input features encompassing elemental composition, microstructural attributes, and thermodynamic properties to enhance prediction accuracies. In this work, we aim to streamline this complexity by employing solely the alloy's elemental composition as the input feature for the machine learning algorithm, improving the hardness while reducing the density of the alloy. We have curated a comprehensive database comprising 544 multi-principal element alloys and developed a robust surrogate model based on these compositions. This composition-driven model is subsequently coupled with principal component analysis (PCA) to facilitate the selection process. Remarkably, through a mere three iterations involving 14 samples, we successfully identified an alloy with an effective specific hardness surpassing the training database maximum by 8.6 %. The proposed composition-driven machine learning delineates a simplified approach for conducting optimization across multiple target material properties.

Investigation of hot deformation behavior and three-roll skew rolling process for hollow stepped shaft of Al–Zn–Mg–Cu alloy

The increasing demand for high-strength lightweight hollow shafts in transportation highlights the need for advanced fabrication techniques. Al–Zn–Mg–Cu alloys, noted for their superior properties, are selected for three-roll skew rolling (TRSR). In TRSR, the material undergoes combined axial tensile and radial compressive stresses. This study evaluates the feasibility of TRSR for producing high-strength lightweight hollow stepped shafts from Al–Zn–Mg–Cu alloy. An integrated approach, including constitutive modeling, hot processing map development, and TRSR numerical simulations/experiments, is employed to optimize the TRSR forming process. The constitutive model was established based on 300°C–450 °C & 0.01–10 s−1 hot compression and 350°C–430 °C & 0.1–5 s−1 high-temperature tensile test data. The established Johnson-Cook optimization by genetic algorithms (GA-JC) model and unified viscoplastic constitutive model, accurately capture the alloy's hot deformation behavior, exhibiting minimal average absolute relative errors (AARE) of 5.431% and 5.808%, respectively. Microstructure evolution analyses shed light on the predominant softening mechanisms, emphasizing dynamic recovery (DRV) at elevated strain rates and diminishing texture intensity with escalating deformation temperatures. The composite hot processing map delineates optimal process parameters (400°C–450 °C & 0.1s−1-1s−1), facilitating informed decision-making in manufacturing practices. The validation of numerical simulations through TRSR forming experiments with initial temperature of 450 °C for the billet and axial moving speed of 10 mm/s for the chuck in affirms the feasibility of producing hollow stepped shafts from high-strength Al–Zn–Mg–Cu alloy. Close agreement was found between simulated and experimental wall thickness variations. This study enhances understanding and optimization of TRSR forming for high-strength lightweight alloys, advancing industrial manufacturing methodologies.

Research progress, application and development of high performance 6000 series aluminum alloys for new energy vehicles

For the development of new energy automobile industry and the trend of automobile lightweight have put forward a huge demand for high-strength lightweight materials, so developing high strength aluminum alloys is particularly momentous. As the most widely used aluminum alloy, 6000 series aluminum alloys (Al–Mg–Si alloys) have the advantages such as better mechanical properties, outstanding welding properties, excellent formability and fine processing capability, and therefore have obtained great attention as the structural materials. In addition, the Al–Mg–Si alloys with low density and corrosion resistance not only reduce the total weight of the car, but also extend the service life when subjected to chemical corrosion, which effectively achieve energy saving and emission reduction. This paper summarizes the research progress of 6000 series aluminum alloys, in particular, and reviews the methods of microalloying and particle strengthening, and their effects on the microstructure and properties of the alloy, thus providing a reference for the subsequent development of high-performance aluminum alloys in automobile and aerospace industries.

Alternating Cu segregation and its stabilization mechanism for coherent [formula omitted] precipitates in Al–Zn–Mg–Cu alloys

The 7000 series (Al–Zn–Mg) Al-alloys are renowned for their exceptional “lightweight-high strength” properties, primarily owing to nano-sized meta-stable η′ precipitate as the main strengthening phase. However, these η′ precipitates are susceptible to transforming into the stable η2 phase at elevated temperatures, resulting in a decline in strength. To mitigate this, Cu-segregation has been long proposed as a promising method for stabilizing these meta-stable precipitates. However, the mechanisms involved have not been fully understood. In this study, we conducted a thorough investigation on the structural and energetic changes between Cu-free and Cu-segregated η' and η2 precipitates. Utilizing DFT calculations and HAADF-STEM characterizations, we uncovered a distinctive alternating Cu-segregation pattern. This pattern induces significant structural modifications within the bulk of η' precipitates and at the precipitate-matrix interface, markedly enhancing their interfacial and bulk energetics. We believe these modifications are the key factor in improving precipitate stability. Based on our findings, the underlying mechanism of solute segregation was elucidated and a novel strategy for optimal design of Al–Zn–Mg alloys was proposed.

Optimisation of mechanical properties and pore structure of lightweight geopolymer concrete

Lightweight geopolymer has good physical and mechanical properties, thermal and chemical stability and low carbon dioxide emissions. The development of high-strength lightweight geopolymer concrete (LGC) for load-bearing structures can expand geopolymer applications. The use of ground granulated blast-furnace slag (GGBFS) to improve the mechanical properties and pore structure of LGC was investigated. The ultimate compressive stress of LGC containing GGBFS were analysed, as well as the variation in microscopic pore structure. Specimens of LGCs with different strengths (LC20, LC30 and LC40) were investigated. As the GGBFS content increases, the ultimate compressive stress and specific strength of LGC increases, while the strain corresponding to the peak stress decreases, indicating that the mechanical properties and deformation resistance of LGC are improved. The carbon dioxide emissions of LGC are less than those of cement-based lightweight concrete, indicating that LGC has good sustainability. Moreover, the addition of GGBFS can produce more gel and reduce the volume proportion of capillary pores and air pores, resulting in LGC densification. Recommended GGBFS contents for strength grades LC20, LC30 and LC40 are 0–12.7%, 12.7–24.6% and 24.6–30%, respectively. The LGC is lightweight and has high strength, and has potential for application in civil engineering.

Exploratory Study on the Application of Graphene Platelet-Reinforced Composite to Wind Turbine Blade.

With the growth of the wind energy market and the increase in the size of wind turbines, the demand for advanced composite materials with high strength and low density for wind turbine blades has become imperative. Graphene platelets (GPLs) stand out as highly premising reinforcements due to their exceptional physical properties, resulting in their widespread adoption in the composite industry in recent years. The present study aims to analyze the applicability of a graphene-platelet-reinforced composite (GPLRC) to wind turbine blades in terms of structural performance. A finite element blade model is constructed by referring to the National Renewable Energy Laboratory (NREL) 5 MW wind turbine, and its reliability is verified through a convergence test. The performance of the wind turbine blade is quantitatively examined in terms of the deflection and stress, natural frequencies, and twist angle. The applicability of the GPL-reinforced wind blade is explored through a comparison with wind blades manufactured with glass fiber and carbon nanotubes (CNTs). The comparison indicates that the performance of a wind blade can be remarkably improved by reinforcing with GPLs instead of traditional fillers, and the weight of not only the wind blade itself but also the wind turbine system can be remarkably reduced. The present results can be useful in the development of next-generation high-strength lightweight wind turbine blades.

Strengthening fire damaged light weight high strength reinforced concrete beams through BFRP grid and ECC jackets

Strengthening fire damaged light weight high strength reinforced concrete beams through BFRP grid and ECC jackets

Compressive Properties of Basalt Fibers and Polypropylene Fiber-Reinforced Lightweight Concrete.

With the development of high-rise and large-scale modern structures, traditional concrete has become a design limitation due to its excessive dead weight. High-strength lightweight concrete is being emphasized. Lightweight concrete has low density and the characteristics of a brittle material. This is an important factor affecting the strength and ductility of the lightweight concrete. To improve these shortcomings and proffer solutions, a three-phase composite lightweight concrete was prepared using a combination of tumbling and molding methods. This paper investigates the various influencing factors such as the stacking volume fraction of GFR-EMS, the type of fiber, and the content and length of fiber in the matrix. Studies have shown that the addition of fibers significantly increases the compressive strength of the concrete. The compressive strength of concrete with a 12 mm basalt fiber (BF) (1.5%) admixture is 9.08 MPa, which is 62.43% higher than that of concrete without the fiber admixture. The compressive strength was increased by 27.53 and 21.88% compared to concrete containing 3 mm BF (1.5%) and 0.5% BF (12 mm), respectively. Fibers can fill the pore defects within the matrix. Mutually overlapping fibers easily form a network structure to improve the bond between the cement matrix and the aggregate particles. The compressive strength of lightweight concrete with the addition of BF was 16.71% higher than that with the addition of polypropylene fiber (PPF) with the same length and content of fibers. BF has been shown to be more effective in improving the mechanical properties of concrete. In this work, the compressive mechanism and optimum preparation parameters of a three-phase composite lightweight concrete were analyzed through compression tests. This provides some insights into the development of lightweight concrete.

Atomic-Scale Insights into the Effects of the Foaming Degree on the Glass-Ceramic Matrix Derived from Waste Glass and Incineration Bottom Ash.

Precise management of the inverse correlation between the total porosity and compressive strength is crucial for the progress of foaming glass-ceramics (FGCs). To deeply understand this relationship, we investigated the atomic-level transformations of five CO2-foaming FGC samples using molecular dynamics simulation. The short-range and intermediate-range structures of the FGCs with varying total porosities (36.68%, 66.28%, 66.96%, 72.21%, and 79.88%) in the system were elucidated. Na cations were observed to exhibit a strong interaction with CO2, accumulating at the surface of the pore wall and influencing the oxygen species. Therefore, the change in the atomic structure of the matrix was accompanied by an increase in the total porosity with an increasing CO2 content. Specifically, as the total porosity increased, the bridging oxygen content within the FGCs rose accordingly. However, once the total porosity exceeded 66.96%, the bridging oxygen content began to decline. This observation was significant considering the role of the bridging oxygen content in forming a continuous cross-linked network of chemical bonds, which contributed to the enhanced mechanical strength. Consequently, the influence of the total porosity on the oxygen species resulted in a two-stage reduction in the compressive strength. This study offers valuable insights for the development of high-strength lightweight FGCs.

Resource recovery of sludge incineration residue in lightweight aggregate: Performance mechanism, and environmental safety analysis

In response to escalating global environmental concerns and the need for sustainable waste management, this study explores the transformative potential of high-temperature sintering in converting sludge incineration residues (SIR) into lightweight aggregates. The research investigates the influence of sintering temperature and time on the physical, mechanical, and environmental characteristics of the resulting aggregates. High-strength lightweight aggregates with optimal properties are achieved at 1085 ℃ and 10 minutes, exhibiting favorable freeze-thaw resistance. Microscopic analyses reveal the presence of glassy substances in the aggregates, with higher sintering temperatures leading to increased glassy content but also more substantial pores. Importantly, high-temperature sintering significantly reduces the leaching rate of heavy metal ions. This study contributes valuable insights into the micro-characteristics and environmental safety of SIR-sintered lightweight aggregates, providing a sustainable solution for waste utilization in the development of high-performance construction materials.

Failure mechanisms of lightweight high strength Si/SiC non-uniform lattice structures by SLS/RMI

Silicon Carbide (SiC) ceramic lattice structures were pivotal in advancing space technology and other sectors by merging structural lightness with high strength. This study explored non-uniform lattice designs tailored for specific load-bearing applications to maximize lightness, although machining such SiC structures proved challenging due to their high hardness and wear resistance. Selective Laser Sintering (SLS) was employed to fabricate non-uniform lattice structures featuring graded volume fractions. Micro computed tomography (Miro-CT) characterized the geometric characteristics of the macroscopic non-uniform lattice structure. Extensive investigations were conducted on the impact of these gradient structures on the quasi-static compressive behavior and mechanical properties of SiC ceramics, revealing that the R-A structure achieved a maximum compressive strength of 14.989 MPa and a specific strength of 13.268 × 10³ N·m/kg, approximately double that of a uniform structure. Furthermore, a finite element model (FEM) was established to verify and predict the mechanical and fracture responses of SiC-based structures, showing effective dispersion of stress concentration along the outer rim of the R-A structure, markedly alleviating the usual stress concentration found in traditional lattices and averting catastrophic failure. The alignment between experimental and simulation outcomes substantiated these findings.

Validation of a ray-tracing-based guided Lamb wave propagation methodology in aerostructures

Validation of a ray-tracing-based guided Lamb wave propagation methodology in aerostructures

Development of an eco-friendly high-strength lightweight concrete using pre-treated coconut shell aggregate and ground-granulated blast furnace slag

Development of an eco-friendly high-strength lightweight concrete using pre-treated coconut shell aggregate and ground-granulated blast furnace slag

Microstructure and properties of high-strength lightweight ceramsites customised with ultra-fine copper tailings

The accumulation of copper tailings not only consumes a significant amount of land resources but also incurs substantial treatment expenses and causes environmental pollution. This article presents an investigation on the feasibility of utilizing ultra-fine copper tailings (CTs), polishing slag (PS), and fly ash (FA) to produce customised high-strength ceramsites for treating and reusing copper tailings.Additionally, the effects of raw material mass ratio and sintering temperature on the physical properties, thermal properties, chemical structure, and expansion mechanism of the high-strength ceramsites were investigated. The experimental results revealed that the well-formed ceramsites exhibited an apparent density of 486–2304 kg/m3, a bulk density of 288–1659 kg/m3, a 1-h water absorption rate of 0.13–3.9 %, and a particle compressive strength of 0.87–22.4 MPa with copper tailings content of 50∼100 % under preheating temperature 950 ℃ for 40 min and sintering temperature 1195–1225 ℃ for 40 min. The XRD analysis of crystal phases indicated that the mineral compositions of ceramsites contained quartz, anorthite, albite, and mullite. Moreover, the FTIR spectra displayed that [AlO4] and [SiO4] were interconnected into a complementary network which enhanced the strength of ceramsites. Additionally, the microstructure analysis revealed that more evenly distributed and smaller pore structures and rougher matrix were associated with higher compressive strength. The temperature difference between the interior and exterior led to the preferential formation of a slag phase which exerted a bonding effect on the composite feldspar phase. These findings suggest that ultra-finecopper tailings could be recycled in artificial aggregate technology in concrete engineering, and provide theoretical support for the large-scale utilization of tailings.