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Aero-engine components endure combined high and low cycle fatigue (CCF) loading during service, which has attracted more research attention in recent years. This study aims to construct a new framework for the prediction of probabilistic fatigue life and reliability evaluation of an aero-engine turbine shaft under CCF loading if considering the material uncertainty.

To study the CCF failure of the aero-engine turbine shaft, a CCF test is carried out. An improved damage accumulation model is first introduced to predict the CCF life and present high prediction accuracy in the CCF loading situation based on the test. Then, the probabilistic fatigue life of the turbine shaft is predicted based on the finite element analysis and Monte Carlo analysis, where the material uncertainty is taken into account. At last, the reliability evaluation of the turbine shaft is conducted by stress-strength interference models based on an improved damage accumulation model.

The results indicate that predictions agree well with the tested data. The improved damage accumulation model can accurately predict the CCF life because of interaction damage between low cycle fatigue loading and high cycle fatigue loading. As a result, a framework is available for accurate probabilistic fatigue life prediction and reliability evaluation.

The proposed framework and the presented testing in this study show high efficiency on probabilistic CCF fatigue life prediction and can provide technical support for fatigue optimization of the turbine shaft.

The novelty of this work is that CCF loading and material uncertainty are considered in probabilistic fatigue life prediction.

This study aims to explain the impact of donations to a charity, company-cause fitting, corporate reputation, corporate philanthropic involvement and message content on Saudi consumers who purchase products that are promoted using cause-related marketing (CrM) campaigns.

Structural equation modelling partial least square is used to analyse the responses of 293 Saudi respondents.

Using Smart-PLS, the results show that donation size is positively related to the Saudi consumer’s purchase intention. However, differences in the donation amount did not affect the purchase intention. Regardless of the cause that motivates firms to donate money to philanthropic organisations, Saudi customers do not generally pay attention to the company-cause fit association. Retail corporate reputation, corporate philanthropic involvement and message content positively influence the purchase of products sold using CrM campaigns. This study explores the psychological and social attitudes Saudi customers demonstrate towards CrM campaigns. Regardless of corporation motives, Saudi customers care about charitable deeds. Moreover, positive message framing is effective when the content is emotive, comprehensive and persuasive.

This study explores the psychological and social attitudes Saudi customers pay towards CrM campaigns. The message content relied significantly upon the cause fit and the magnitude of the donated money. Marketing research would benefit from investigating the role of applying efficient persuasive tactics to convey and frame public messages.

The current study aims to develop a 3D-printed continuous metal fiber-reinforced recycled thermoplastic composite using an in-nozzle impregnation technique.

Recycled acrylonitrile butadiene styrene (RABS) plastic was blended with virgin ABS (VABS) plastic in a ratio of 60:40 weight proportion to develop a 3D printing filament that was used as a matrix material, while post-used continuous brass wire (CBW) was used as a reinforcement. 3D printing was done by using a self-customized print head to fabricate the flexural, compression and interlaminar shear stress (ILSS) test samples to evaluate the bending, compressive and ILSS properties of the build samples and compared with VABS and RABS-B samples. Moreover, the physical properties of the samples were also analyzed.

Upon three-point bend, compression and ILSS testing, it was found that RABS-B/CBW composite 3D printed with 0.7 mm layer width exhibited a notable improvement in maximum flexural load (L_max), flexural stress at maximum load (sf_max), flex modulus (E_f) and work of fracture (WOF), compression modulus (E_c) and ILSS properties by 30.5%, 49.6%, 88.4% 13.8, 21.6% and 30.3% respectively.

Limited research has been conducted on the in-nozzle impregnation technique for 3D printing metal fiber-reinforced recycled thermoplastic composites. Adopting this method holds the potential to create durable and high-strength sustainable composites suitable for engineering applications, thereby diminishing dependence on virgin materials.

Continuous fiber reinforced thermoplastic composites (CFRTPCs) are becoming more significant in industrial applications but are limited by the high cost of molds, the manufacturing boundedness of complex constructions and the inability of special fiber alignment. The purpose of this paper is to put forward a novel three-dimensional (3D) printing process for CFRTPCs to realize the low-cost rapid fabrication of complicated composite components.

For this purpose, the mechanism of the proposed process, which consists of the thermoplastic polymer melting, the continuous fiber hot-dipping and the impregnated composites extruding, was investigated. A 3D printing equipment for CFRTPCs with a novel composite extrusion head was developed, and some composite samples have been fabricated for several mechanical tests. Moreover, the interface performance was clarified with scanning electron microscopy images.

The results showed that the flexural strength and the tensile strength of these 10 Wt.% continuous carbon fiber (CCF)/acrylonitrile-butadiene-styrene (ABS) specimens were improved to 127 and 147 MPa, respectively, far greater than the one of ABS parts and close to the one of CCF/ABS (injection molding) with the same fiber content. Moreover, these test results also exposed the very low interlaminar shear strength (only 2.81 MPa) and the inferior interface performance. These results were explained by the weak meso/micro/nano scale interfaces in the 3D printed composite parts.

The 3D printing process for CFRTPCs with its controlled capabilities for the orientation and distribution of fiber has great potential for manufacturing of load-bearing composite parts in the industrial circle.

Presents an alternative lower bound to the elastic buckling collapse of thin shells of revolution, in comparison with results from geometrically non‐linear elastic analysis. The numerical finite element method is based on axisymmetric rotational shell elements whose strain‐displacement relations are described by Koiter’s small finite deflection theory, with displacements expanded circumferentially using a Fourier series. First, compares the reduced stiffness linear analysis, based on the buckling equation without incremental linear in‐plane energy components corresponding to the lowest eigenmode (for a particular cylindrical shell under external pressure), with the results obtained by Batista and Croll. Second, the non‐linear astatic (quasi‐static) elastic analysis to clamped spherical caps under uniform external pressure is carried out in order to compare the results from a reduced stiffness analysis from viewpoints of not only buckling loads, but also total potential energy. Argues that the astatic buckling loads may relate to reductions due to a specific imperfection effect on elastic buckling collapses.

This study aims to present an experimental approach to develop a high-strength 3D-printed recycled polymer composite reinforced with continuous metal fiber.

The continuous metal fiber composite was 3D printed using recycled and virgin acrylonitrile butadiene styrene-blended filament (RABS-B) in the ratio of 60:40 and postused continuous brass wire (CBW). The 3D printing was done using an in-nozzle impregnation technique using an FFF printer installed with a self-modified nozzle. The tensile and single-edge notch bend (SENB) test samples are fabricated to evaluate the tensile and fracture toughness properties compared with VABS and RABS-B samples.

The tensile and SENB tests revealed that RABS-B/CBW composite 3D printed with 0.7 mm layer spacing exhibited a notable improvement in Young’s modulus, ultimate tensile strength, elongation at maximum load and fracture toughness by 51.47%, 18.67% and 107.3% and 22.75% compared to VABS, respectively.

This novel approach of integrating CBW with recycled thermoplastic represents a significant leap forward in material science, delivering superior strength and unlocking the potential for advanced, sustainable composites in demanding engineering fields.

Limited research has been conducted on the in-nozzle impregnation technique for 3D printing metal fiber-reinforced recycled thermoplastic composites. Adopting this method holds the potential to create durable and high-strength sustainable composites suitable for engineering applications, thereby diminishing dependence on virgin materials.

The mesoscale structure (MS) has a significant impact on the mechanical performance of parts made by additive manufacturing (AM). This paper aims to explore the design and fabrication of force-flow guided reinforcement mesoscale structure (FFRMS) compared with the homogeneous mesoscale structure (HMS), which is inconsistent with the stress field for a given load condition. Some cases were presented to demonstrate the mechanical properties of FFRMS in terms of MS combined with quasi-isotropy and anisotropy.

The paper consists of four main sections: the first developed the concept of FFRMS design based on HMS, the second explored volume fraction control for the proportion of force-flow lines in terms of mechanical property requirement, and the third presented a sequence stacking theory and practical manufacturing process framework and the final sections provided some application case studies.

The main contributions of this study were the definition and development of the FFRMS concept, the application framework and the original case studies. As an example, a typical lug designed with the proposed FFRMS method was fabricated by three different AM processes. The test results showed that both the strength and stiffness of the specimens are improved greatly by using the FFRMS design method.

The superposition of HMS as the basement and force-flow as an indication of the stiffener, leading to a heterogeneous structure, which exhibits more efficient and diversified means compared with the traditional way of increasing the HMS density merely.

The purpose of this paper is to investigate the performances of vegetable based cutting fluids by comparing tool life, surface roughness and cutting force during end milling of AISI 304 stainless steel. In the experiments, three different vegetable based cutting fluids developed from sunflower and canola oils (SCF‐II with 8% extreme pressure (EP), CCF‐II without EP and CCF‐II with 8% EP) and a commercial type of semi‐synthetic cutting fluid were used. Cutting fluid was applied to the cutting zone via two nozzles.

Effects of different cutting speeds (100, 150 and 200 m/min) and different feed rates (0.2, 0.25 and 0.3 mm/rev) on tool life, surface roughness and cutting force in milling of AISI 304 stainless steel were investigated. Depth of cut and step over were kept constant as 0.3 mm and 10 mm at both conditions, respectively.

Results indicated that CCF‐II with 8% EP cutting fluid showed better performance than the others.

In this study, effect of extreme pressure additive on milling performance was investigated.

Freight carriers operating in a spot-market environment are faced with uncertain future capacity demand, actual revenues, and properties of freight items. They require information about the expected future consumption of limited capacity to derive suitable request acceptance decisions. The purpose of this paper is to present a new idea to improve the handling of inaccurate information on the weight and volume of upcoming requests.

The authors start with the definition of a new mathematical optimization model as the backbone of a capacity control system. This model is embedded within a rolling-horizon decision-making process involving consecutively arriving requests. Computational simulation experiments are carried out to evaluate the applicability and efficiency of the proposed decision support system. The authors investigate how the new model contributes towards keeping the negative impacts of inadequate forecasts of the expected volume of future requests as low as possible.

In traditional application fields of capacity control (airline ticketing or hotel reservations) the physical extent of a request is always 1 (set/bed/room). In road-based freight transportation the variety of the physical extent of requests is much more complicated and complex. The major finding is that existing capacity control approaches are unable to meet the special requirements of road-haulage. Innovative capacity control features are necessary in order to cope with the higher request portfolio complexity.

This paper addresses the requirements of a capacity control system for road-based freight transportation. An innovative decision support system is evaluated. For the first time, the authors present a comprehensive quantitative simulation study dedicated to this complicated decision-making situation.

The U.S. Congress has been struggling to create a comprehensive energy program. A key component of the present attempt, recommended by President Carter, is a synthetic fuel program. In July of 1979, the President asked for an $88 billion “crash program” to encourage development of synthetic fuels. To date, a three month struggle to reach a consensus between House and Senate conferees has brought only limited results. Compromise is emerging in the form of a proposal for a “synthetic fuels corporation.” The body would have the authority to disperse $20 billion in the form of federal loan guarantees and purchase agreements with more money to become available later.