Potential For Weight Reduction Research Articles

Design and experiment on light weight hydraulic cylinder made of carbon fiber reinforced polymer

Hydraulic cylinders are widely used in mobile equipment such as aircraft, construction machinery, and heavy-duty robots. The large weight of the hydraulic cylinder seriously restricts the performance of the whole machine in terms of maneuverability, carrying capacity, endurance time, and energy saving. Using CFRP instead of metal can improve the weight reduction potential of a hydraulic cylinder. The law was found from the requirement for internal leakage prevention of hydraulic cylinder to the design of CFRP layer parameters. According to this law, the design method of radial stiffness of CFRP hydraulic cylinder is proposed. The composite structure of CFRP hydraulic cylinder was designed for the specific requirements of using CFRP to manufacture hydraulic cylinders. As an example, the prototype developed based on the radial stiffness design method and composite structure has reduced weight by 56.86% while maintaining the same performance as the conventional metal hydraulic cylinder. The light weighting of hydraulic cylinders brings considerable economic and environmental benefits.

Tribological Behavior of High-Strength Aluminum Alloys in Combination with Dry Lubricants at High Forming Temperatures

High-strength aluminum alloys provide great potential for weight reduction in vehicle and aircraft production. Nevertheless, forming of these materials is limited at room temperature. Thermally supported forming operations such as hot forming and quenching (HFQ®) allow forming of components without failure and reduced springback. Currently, the adhesive wear and high friction limit the use of HFQ®-operations for high-strength aluminum alloys. Out of this reason, the present paper describes the tribological performance of new developed dry lubricants at elevated temperatures for the alloy AA7075. For this purpose, strip drawing tests were carried out in a modified open tribological system at temperatures between 20 °C and 400 °C. Additionally, the melting behavior of these lubricants, as well as the variation of the lubricant thickness, were investigated. The results show a reduction of the coefficient of friction at elevated temperatures.

Methodical approach for manufacturing-oriented concept development for Tailored Textiles

Tailored Textiles (TT) are load-optimized fiber-based composites, providing a high potential for weight reduction as well as cost-saving compared to conventional composites. Compared to isotropic materials (e.g. most metals and plastics), anisotropic fiber-based composites require the definition of their internal fiber orientation. This additional development step results in strong interdependencies between the different disciplines: structural engineering, material engineering, and manufacturing planning. This provides a high complexity in the Product Development Process (PDP) and prevents the utilization of TT’s potential in industrial applications.This paper presents a customized PDP to develop TT structures, optimized for weight and cost reduction simultaneously. By linking the expert models for structural and cost engineering the necessity of iteration loops can be minimized. To meet the best compromise between a wide solution and the required development effort, customized model-fidelities are assigned to the different milestones during the PDP. This approach enables an early cost and performance evaluation and supports the engineer in his decisions in all phases of the PDP, such as the decision whether to design the component as a fiber-reinforced plastic (FRP) or the selection of the manufacturing technology for TT. Thus, based on this cost and performance evaluation, early decisions can be made about possible manufacturing technologies, reducing the complexity for the subsequent iterations of the detailed development process. Furthermore, the relevant development tasks and responsibilities of the involved entities are defined. The core entities are represented by project planning, production planning, structural engineer and manufacturing planning. The PDP’s scope covers the process from the initial definition of product requirements to manufacturing planning.

Preformado rápido para aplicaciones de automoción mediante instalaciones flexibles y automatizadas

The use of polymer matrix composites and, in particular, based on carbon fiber, is awakening more and more interest in the automotive sector, due to the great weight reduction potential they offer for the lightening of vehicle structures. The case of the BMW (with the i3, i8 and 7 Series) and some other manufacturers, represent the first cases of use of "large scale production" with these materials, with a growth perspective provided by the electric vehicle. To achieve a mass implementation of these new materials it is a key factor the development of processes and equipment that allow manufacturing with very short cycle times. Preforming is the key stage where the fiber stacking takes the form of the injection mold in which it will be introduced later. This stage of the process is the one that has a greater impact on the cost of the overall process, so it is especially necessary to develop optimization and automation techniques for rapid preforming. In this context, Fagor Arrasate, with the aim of offering its customers a competitive installation, has created and led a project in which it has collaborated with Tecnalia to develop pre-forming installations for the automotive sector.. A fast preforming process based on preheating and cold stamping has been developed combined with an automatic material feeding based on a transfer system and also completed with the automation of the initial stacking and the trimming of the final preform. The capabilities of this installation have been validated for an automotive demonstrator.

A geometrical parametric study of side door reinforced beams under lateral impact load

In this work, crash characteristics of side door reinforced beams under low speed impact were investigated. The side door panels of three different cross-sections, namely, circular, U and W shapes were considered. The advanced high strength (AHS) steel grade 1000 was used and both quasi-static and dynamic tensile tests were carried out for obtaining the rate-dependent flow stress behaviour. The geometries of all panels were modified with a specified design space constraint. FE simulations of profile variants under lateral impact load were carried out and resulting peak forces and maximum intrusions were afterwards determined. The most effective geometrical parameters for enhancing impact resistance of each reinforced beam were identified. The Wshape panel exhibited the greatest compromise of increasing crushing force efficiency, potential of weight reduction and minimizing structural damage. Finally, side door beams with combined best configurations were proposed and their crashworthiness including normalized specific energy absorptions were compared.

Exploring the feasibility of thermal digestion process: A novel technique, for the rapid treatment and reuse of solid organic waste as organic fertilizer

The study developed a holistic approach based on the thermal digestion (TD) technique for the rapid conversion of solid organic waste (SOW) into nutrient-rich organic fertilizer. The effect of digestion temperatures (110oC–170 °C) on the weight reduction from the SOW and the availability of the nutrients were thoroughly investigated. The potential weight reduction of 75.2% was achieved at a temperature of 150 °C for 135 min, as illustrated by response surface methodology (RSM). Scanning electron microscope (SEM) study was carried out to analyze the changes into surface morphology of the sample before and after the digestion. Fourier transform infrared (FTIR) analysis was conducted to study the mineralization process. Thermogravimetric-Differential thermal analysis (TG-DTA) was conducted to study the thermal decomposition behavior of the untreated and digested SOW. The digested SOW resulted high nutrient-rich end product (N-2.08 ± 0.01%, P-0.42 ± 0.00%, & K-1.65 ± 0.06%), which have potential to be used as organic fertilizer. Fertilizing potential of the digested SOW complied with the delineated norms of the organic fertilizer given by the Fertilizer Association of India (2019). Maturity and phytotoxicity of the digested SOW were explored on the basis of C:N ratio (18.07 ± 0.17), humification index (3.43 ± 0.02), heavy metals content, as well as through seed germination index (>90%). The proposed technology may lead to the paradigm shift in waste management and provides an efficient alternative for the recycling of nutrients.

Syntactic Iron Foams' Properties Tailored by Means of Case Hardening via Carburizing or Carbonitriding.

Metal foam inserts are known for their high potential for weight and vibration reduction in composite gear wheels. However, most metal foams do not meet the strength requirements mandatory for the transfer of sufficiently high levels of torque by the gears. Syntactic iron and steel foams offer higher strength levels than conventional two-phase metal foams, thus making them optimum candidates for such inserts. The present study investigates to what extent surface hardening treatments commonly applied to gear wheels can improve the mechanical properties of iron-based syntactic foams. Experiments performed thus focus on case hardening treatments based on carburizing and carbonitriding, with subsequent quenching and tempering to achieve surface hardening effects. Production of samples relied on the powder metallurgical metal injection molding (MIM) process. Syntactic iron foams containing 10 wt.% of S60HS hollow glass microspheres were compared to reference materials without such filler. Following heat treatments, the samples’ microstructure was evaluated metallographically; mechanical properties were determined via hardness measurements on reference samples and 4-point bending tests, on both reference and syntactic foam materials. The data obtained show that case hardening can indeed improve the mechanical performance of syntactic iron foams by inducing the formation of a hardened surface layer. Moreover, the investigation indicates that the respective thermo-chemical treatments can be applied to composite gear wheels in exactly the same way as to monolithic ones. In the surface region modified by the treatment, martensitic microstructures were observed, and as consequence, the bending limits of syntactic foam samples were increased by a factor of three.

Reversion of natural ageing and restoration of quick bake-hardening response in Al-Zn-Mg-Cu alloy

The high-strength Al-Zn-Mg-Cu alloy provides much better dent resistance and weight-reduction potential compared to the conventional Al alloys used for the automobile body panels. However, natural ageing (NA) significantly reduces the formability of Al-Zn-Mg-Cu alloy. The reversion of natural ageing has been systematically investigated by hardness test, tensile test, differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). Substantial reversion of natural ageing and thus hardness decrease occurs immediately upon thermal treatment at 120–210 °C in an Al-Zn-Mg-Cu alloy. Although the hardness of the most reverted state decreases with increasing temperature, the lowest hardness is still higher than the as-quenched state by 30HV. As revealed by the complementary DSC and TEM observations, this is ascribed to the synchronization of the dissolution and the re-precipitation of the solutes in the NA clusters during reversion ageing. Reversion at 180–210 °C for less than 30 s leads to a hardness decline of 40HV. The hardening kinetics during NA after reversion is slower than that during first-time NA due to the reduced vacancy concentration. Artificial ageing at 180 °C for 30 min after secondary NA of less than 24 h induces intensive precipitation of plate-like pre-η phases and a giant strength increase of 188–204 MPa. Potential use of high strength Al-Zn-Mg-Cu alloy in automobile body panels could be realized by appropriate reversion treatment improving the formability and the quick bake hardening response.

A design concept of active cooling for tailored forming workpieces during induction heating

The demand for lightweight construction is constantly increasing. One approach to meet this challenge is the development of hybrid components made of dissimilar materials. The use of the hybrid construction method for bulk components has a high potential for weight reduction and increased functionality. However, forming workpieces consisting of dissimilar materials requires specific temperature profiles for achieving sufficient formability. This paper deals with the development of a specific heating and cooling strategy to generate an inhomogeneous temperature distribution in hybrid workpieces. Firstly, the heating process boundaries with regard to temperature parameters required for a successful forming are experimentally defined. Secondly, a design based on the obtained cooling strategy is developed. Next a modelling embedded within an electro-thermal framework provides the basis for a numerical determination of admissible cooling rates to fulfil the temperature constraint. Here, the authors illustrate an algorithmic approach for the optimisation of cooling parameters towards an effective minimum, required for applicable forming processes of tailored forming.

Effects of Graphite Oxide Nanoparticle Size on the Functional Properties of Layer-by-Layer Coated Flexible Foams.

The exploitation of self-assembled coatings comprising graphite oxide (GO) nanoplates has been recently demonstrated as a promising route to improve the fire safety of flexible polyurethane (PU) foams. However, limited knowledge has been gathered on the correlations between the physical and chemical properties of different GO grades and the performance obtained in this application. This work addresses the effects of the nanoparticle dimensions on the layer-by-layer (LbL) assembly and flame-retardant properties of GO-based coatings deposited on PU foams. To this aim, three GO bearing different lateral sizes and thicknesses were selected and LbL-assembled with chitosan (CHIT). Coating growth and morphology were evaluated by FTIR and FESEM, respectively. The resulting CHIT/GO assemblies were demonstrated to be capable of slowing down the combustion of the PU both in flammability and forced combustion tests. In addition, compressive stress/strain tests pointed out that the LbL-coated foams (22–24 kg/m3) could easily replace denser commercial PU foam (40–50 kg/m3) with weight reduction potentials in the transport field. These results are correlated with the properties of the employed GO. The production of assemblies characterized by a high density of CHIT/GO interfaces is identified as the main parameter controlling the FR efficiency and the mechanical properties of the coatings.

Design of a composite nose wheel for commercial aircraft

Innovative approaches for lightweight design of components can contribute significantly to reduced fuel consumption and emissions of future aircraft. Within the framework of the European aviation research program Clean Sky 2, an innovative design of an aircraft nose wheel for the A320 is developed using carbon fiber reinforced plastics (CFRP) in order to demonstrate a weight reduction potential of 27% compared to conventional designs. In the present paper, the approach of the development process and the final detailed design of the composite aircraft wheel as well as a manufacturing concept are presented, various design challenges are highlighted and the solutions developed to meet them are discussed. Within a concept phase different structural design principles for the wheel are analyzed, taking into account the challenging load cases during different phases of aircraft operation. The selected innovative design principle is further elaborated into a detailed design considering design challenges such as space, installation, and safety requirements, as well as integration of bearings, seals and joint solutions. Also, structural analysis of the composite components via FEA and experimental validation of the joints are discussed. In addition, the manufacturing concept for the complex wheel geometry via resin transfer molding (RTM) using carbon non-crimp fabrics is presented and an outlook on the future manufacturing and testing of wheel prototypes is given.

55 - Comparative Analysis of A1c and Weight Reduction Potential of Subcutaneous GLP-1 Receptor Agonists in a Real-World Setting

55 - Comparative Analysis of A1c and Weight Reduction Potential of Subcutaneous GLP-1 Receptor Agonists in a Real-World Setting

Cardiovascular outcomes trials with glucagon-like peptide-1 receptor agonists: A comparison of study designs, populations and results.

Despite treatment advances leading to improved outcomes over the past 2 decades, cardiovascular (CV) disease (CVD) remains the leading cause of morbidity and mortality in people with diabetes. People with type 2 diabetes (T2D) have a 2‐ to 4‐fold increased risk of CVD and CV death. Individuals with T2D have not seen the same improvements in CV morbidity and mortality as those without T2D. Given this, it is important to understand the CV impact of drugs used to treat T2D. In patients with T2D, glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) have shown a reduction in HbA1c and body weight regardless of their differences in chemical structure and pharmacokinetic variables. Glycaemic efficacy, accompanied by the potential for weight reduction and a low risk of hypoglycaemia, has moved GLP‐1 RAs to the first treatment of choice following metformin monotherapy in the latest American Diabetes Association treatment guidelines. Additionally, all GLP‐1 RAs have shown CV safety and several have proven CV benefit. GLP‐1 RAs have been evaluated in cardiovascular outcomes trials (CVOTs) of varying sizes, designs and patient populations with differing reported effects on CV outcomes. The purpose of this article is to review the completed GLP‐1 RA CVOTs with special attention to how their design, size, patient populations and conduct may influence the interpretation of results.

Self-healing composites structure using multiple through-thickness microvascular channels

Self-healing composites using microvascular channel networks have been intensively studied. Microvascular networks in composite in-plane directions are normally utilized to deliver healing agents to damaged areas. However, this channel configuration is not optimal to form robust networks and to infuse large damaged areas. This study proposes a self-healing system using multiple short microvascular channels in the through-thickness direction. First, the advantage of using this channel configuration was confirmed through delamination filling tests. Next, the feasibility of this channel configuration was evaluated by tensile tests and four-point bending tests. Double cantilever beam tests were then conducted to confirm its healing function. Finally, this system was applied to composite stiffened panels and the healing performance was evaluated using compression testing following panel indentation. The healing system almost fully recovered the original strength, confirming its high potential under practical conditions. Additionally, the weight reduction potential of the self-healing system was discussed through a strength comparison of specimens with different thicknesses.

The Modelled Population Obesity-Related Health Benefits of Reducing Consumption of Discretionary Foods in Australia.

Over one third of Australians’ daily energy intake is from discretionary foods and drinks. While many health promotion efforts seek to limit discretionary food intake, the population health impact of reductions in the consumption of different types of discretionary foods (e.g., sugar-sweetened beverages (SSBs), confectionery, sweet biscuits) has not been quantified. This study estimated the potential reductions in body weight, obesity-related disease incidence, and healthcare cost savings associated with consumption of one less serving per week of different discretionary foods. Reductions in the different types of discretionary food were modelled individually to estimate the impact on energy consumption and population body weight by 5-year age and sex groups. It was assumed that one serving of discretionary food each week was replaced with either a serving of fruit or popcorn, and a serving (375 mL) of SSBs was replaced with coffee, tea, or milk. Proportional multi-state multiple-cohort Markov modelling estimated likely resultant health adjusted life years (HALYs) gained and healthcare costs saved over the lifetime of the 2010 Australian population. A reduction of one serving of SSBs (375 mL) had the greatest potential impact in terms of weight reduction, particularly in ages 19–24 years (mean 0.31 kg, 95% UI: 0.23 kg to 0.37 kg) and overall healthcare cost savings of AUD 793.4 million (95% UI: 589.1 M to 976.1 M). A decrease of one serving of sweet biscuits had the second largest potential impact on weight change overall, with healthcare cost savings of $640.7 M (95% CI: $402.6 M to $885.8 M) and the largest potential weight reduction amongst those aged 75 years and over (mean 0.21 kg, 95% UI: 0.14 kg to 0.27 kg). The results demonstrate that small reductions in discretionary food consumption are likely to have substantial health benefits at the population level. Moreover, the study highlights that policy responses to improve population diets may need to be tailored to target different types of foods for different population groups.

Electrifying Long-Haul Freight—Part I: Review of Drag, Rolling Resistance, and Weight Reduction Potential

Electrifying Long-Haul Freight—Part I: Review of Drag, Rolling Resistance, and Weight Reduction Potential

Rhus coriaria L. (Sumac) in Patients Who Are Overweight or Have Obesity: A Placebo-Controlled Randomized Clinical Trial

Background: The study was designed to examine the efficacy and safety of Rhus coriaria L. (Sumac) supplementation in patients who are overweight or obese. Methods: The study was designed as a parallel two-arm, double-blind, randomized placebo-controlled clinical trial conducted in an endocrinology clinical affiliated by Shiraz University of Medical Sciences at 2016. Fifty patients with body mass index (BMI) ≥ 25 kg/m2 were randomly assigned to receive Sumac supplementation (500 mg twice daily) or placebo for six weeks. The patients were evaluated before and after the intervention in terms of their BMI, waist-hip ratio (WHR), leptin, fasting blood glucose, and insulin resistance index (HOMA-IR). Beside clinical adverse event monitoring, liver and kidney function tests were measured before and after the intervention. Results: Statistically significant decrease in weight, waist circumference, and BMI were observed in the Sumac group, which was more prominent as compared to the placebo after six weeks of intervention (1.34 vs. 0.64 P = 0.003; 1.10 vs. 0.54 P = 0.027, and 0.49 vs. 0.24 P = 0.002, respectively). Insulin resistance was also decreased (0.45 vs. -0.14 P = 0.020). No significant change in leptin and fasting blood glucose was observed. No clinical or laboratory adverse event was observed. Conclusions: Sumac supplementation showed to have a potential weight-reduction effect, along with a positive effect on insulin resistance in patients who were overweight or obese.

On the development of shell buckling knockdown factors for imperfection sensitive conical shells under pure bending

Abstract Thin-walled conical shells are used as adapters between cylindrical shells of different diameters in launch-vehicle systems or as tailbooms in helicopters. A major loading scenario for conical shells is pure bending. The buckling moment of these shells is very sensitive to imperfections (geometry, loading conditions) which results in a critical disagreement between theoretical and experimental results for conical shells under pure bending. The design of these stability critical shells is based on classical buckling loads obtained by a linear analysis which are corrected by a single knockdown factor (0.41 - NASA SP-8019) for all cone geometries. This practice is well established among designers and hasn't changed for the past 50 years because the buckling behavior is till today not very well understood. Within this paper a reduced stiffness analysis for conical shells under pure bending is performed. Data of previous experimental testing campaigns are used to validate the new design criteria for different conical shell geometry configurations. The results show that the application of the new design recommendation for conical shell structures results in increased knockdown factors for the buckling moment which in turn may lead to a significant weight reduction potential. All ABAQUS-Python scripts and the results generated for this article are deposited in the Elsevier repository.

Mechanism-oriented characterization of the load direction-dependent cyclic creep behavior of the magnesium alloys Mg-4Al-2Ba-2Ca and AE42 at room temperature

Due to their low density and high strength-to-weight-ratio magnesium alloys are very attractive for lightweight construction. Especially creep-resistant magnesium alloys can also be applied in the engine area of automobiles and therefore offer a high potential for weight reduction. For a safe and efficient use in such applications at elevated temperatures, a fundamental knowledge of the materials properties under cyclic loading is necessary. The aim of this study is the comparative investigation of the cyclic creep (ratcheting) behavior of magnesium alloys Mg-4Al-2Ba-2Ca and AE42 under different load ratios. Fatigue tests in tensile and compressive load ratios have been performed at room temperature. Fatigue strengths were estimated in load increase tests based on structure-sensitive material reactions. The results were correlated with fatigue lifetimes determined in constant amplitude tests. Furthermore, characteristic deterioration mechanisms were evaluated using a dedicated custom sensor system as well as by concomitant microstructural investigations.

Friction Stir Welding between 6082 and 7075 Aluminum Alloys Thermal Treated for Automotive Applications

The automotive industry demands ecofriendly manufacturing processes and lightweight structures and materials to reduce CO2 emissions and decrease weight and fuel consumption while optimizing overall performance. Aluminum alloys in the 7xxx and 6xxx series offer high potential for weight reduction in automotive and other transportation industries. 7xxx aluminum alloys have the best strength performance among all commercial aluminum alloys. Alloys in the 6xxx series generally have medium-to-high strength, high corrosion resistance, and good formability. Alloys in both the 7xxx and 6xxx series are strengthened by heat treatment. The increased strength-to-weight ratio and the thermal treatment processing open the possibility to use these alloys as possible alternative materials instead of steel in the automotive industry for the fabrication of car body parts. However, their poor formability and weldability are the main drawbacks when these alloys are considered as substitutes of steel and other dissimilar joints during the fabrication of car body parts and the production chain. Recently, Hot Forming and in-die Quenching (HFQ), a patented hot stamping process, has been introduced to manufacture complex-shaped high-strength heat-treatable aluminum alloys. The work described in this article is an experimental investigation of the weldability between AA6082 and AA7075 by Friction Stir Welding (FSW) that considers thermal treatments used during HFQ for automotive applications. The aforementioned FSW base metals, 6082 and 7075, are heat treated according to the solution heat treatment adopted during HFQ to evaluate the effect of the HFQ thermal cycle on the quality of the produced joints. Optical microscopy has been used to characterize the microstructure of the produced joints. The defect-free welded joints are characterized by good mechanical mixing between the joined materials as well as by grain refinement. The mechanical behavior of the produced welded joints was studied and compared with the parent materials, whereas the measured mechanical properties are correlated with the microstructure.