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This study explores development and 3D/4D printing of environmentally friendly bio-composites with enhanced mechanical properties, flame retardancy, and shape memory capabilities. Composite filaments were created by incorporating polylactic acid (PLA) with bamboo charcoal (BC) and then printed using a modified printer equipped with a dual-feed system to accommodate both PLA/BC filaments and continuous flax fibres (CFF). SEM revealed strong fibre-matrix bonding with minimal voids, indicating good interfacial adhesion. Bio-composite properties were characterised through DMA, tensile, three-point bending, flammability, and shape-memory effect tests. Adding 3 wt% BC and CFF significantly increased the tensile strength by 248 % and the flexural strength by 207 % compared to pure PLA. Flame retardancy properties were notably improved, with a 50 % reduction in the burning rate, and underwriters’ laboratories (UL-94) rate and limiting oxygen index (LOI) reached to V-1 rating and 36.8%vol, respectively. DMA tests showed an increase in storage modulus, indicating improved stiffness. Shape memory tests under cold/hot programming protocols demonstrated efficient shape fixation with shape recovery ratios reaching up to 98.9 % for pure PLA and 89 % for PLA/BC/CFF for hot programming. Finally, a conceptual meta-bio-composite was 4D printed, showcasing key achievements such as quasi-zero stiffness, constant force behaviour, enhanced energy absorption/dissipation, and excellent recoverability and reusability. This highlights their potential for applications requiring durability, safety, comfort, and sustainability in sectors such as automotive, aerospace, logistics, construction, and furniture.

Introduction Consumption of ready-to-eat products especially seafood, has become very popular based on the lifestyle during these years. Battered and breaded products are highly acceptable due to their attractive appearance and unique taste. Shrimp and shrimp products are one of the most popular seafood products in many countries because of their unique flavor, nutritional value and texture. The interactions of proteins with other ingredients can play a critical role in the structure of processed foods. Protein-polysaccharide interactions provide functional properties in foods especially when proteins are the main ingredients, such as processed shrimp products without affecting the original flavor of the food. The use of gelling properties of carbohydrates in the formulation of food products is increasingly growing. The wide variety of hydrocolloids have been examined to modify the mechanical, textural and functional properties of shrimp products. In this regard, application of carrageenan, xanthan, and alginate have been reported to improve the physicochemical and sensory attributes of shrimp products. In the present study, surimi was produced and used in combination with different percentages of carrageenan, alginate and xanthan gums in order to simulate breaded shrimp and produce shrimp nuggets with a texture similar to battered and breaded shrimp. Materials and Methods In the first step, surimi was prepared from silver carp fillets. In the next step, shrimp nuggets were produced from obtained surimi in combination with additives (including starch, salt, garlic, and spices) and different percentages (0.5, 1, 1.5 and 2% ) of carrageenan, alginate and xanthan gums. The prepared mixture was kept at 35 °C for 1 hour and then battered and breaded after molding. Physical (expressible water, product yield, and shrinkage), chemical (moisture, fat, and pH), color, texture, and sensory analysis were performed on several samples of shrimp nuggets (containing different percentages of carrageenan, alginate, and xanthan gums) in comparison with the control sample (battered and breaded shrimp immersed in salt and polyphosphate). Results and Discussion Based on the results, the amount of shrinkage decreased in all samples containing gums in comparison with the control (p < 0.05). Shrimp nuggets containing xanthan and alginate showed a lower amount of fat in comparison with the control and the samples containing carrageenan (p < 0.05). The highest amount of pH value observed in the control sample, and the sample containing 1.5 and 2 % alginate showed the lowest amounts of pH. The shrimp nuggets containing 2 % alginate demonstrated the highest amounts of water holding capacity.However, the other samples did not show significant differences with the control (p > 0.05). There were no significant differences between the control and shrimp nuggets containing gums in terms of product yield (p > 0.05). Shrimp nuggets containing 2 % xanthan and the control showed the highest and lowest amounts of brightness, respectively. The highest value of adhesion observed in shrimp nuggets containing 2 % alginate and the control.The lowest amounts of adhesion were observed in shrimp nuggets containing 2 % xanthan, 0.5 % alginate, 1 and 2 % carrageenan (p < 0.05). Samples containing 1% carrageenan showed the highest scores of the sensory attributes of taste, smell, texture and overall acceptance, as same as the control (p ˃ 0.05). Conclusion Hydrocolloid additions were found to be significantly affecting the quality parameters including fat content, pH value, shrinkage and texture of produced shrimp nuggets. Therefore, it seems that producing shrimp nuggets containing 1 % carrageenan showed the nearest physical, chemical, and sensory characteristics to the control (battered and breaded shrimp), and this sample can be used as alternative of battered and breaded shrimp.

Abstract The high fracture strength and exceptional impact resistance of polymer-based composites are of paramount importance to various industries like aerospace, automotive, and construction. The resin transfer molding (RTM) process is used to produce composite samples of superior quality, minimal porosity, and reduced lamination defects. In the present study, the RTM method was employed to fabricate glass fiber-reinforced composites, aiming to investigate their specific mechanical properties and structural performance. The study initially determined the ballistic limit of the produced samples. Subsequently, experimental investigations were carried out to examine the impact of hole drilling on the tensile strength, flexural strength, and impact resistance of the samples. The results revealed that the produced polymer plate demonstrated a ballistic limit with a pressure of 11 bar and a speed of 104 m/s, leading to ball restriction in the plate. The sample without holes showed the highest fracture force, while samples with three and five holes exhibited reduced fracture forces. Additionally, bending force and impact resistance were lower in samples with multiple holes compared to the sample without holes. The impact resistance of the sample with five holes was the lowest among all configurations. The study revealed that the presence of three holes arranged in a row has a lesser impact on reducing the ultimate tensile force compared to the effect of five holes. Moreover, the bending test results indicated that sample failure occurred on the side under tension, resulting in higher bending forces than tensile forces.

Abstract 3D printing of gears via fused deposition modeling (FDM) has been recently introduced as a low‐cost efficient manufacturing method. Different materials have been 3D printed and Acrylonitrile Butadiene Styrene (ABS) with excellent mechanical properties has been found to be promising. However, 3D printed ABS gears possess a high level of abrasion rate. This paper introduces a new class of ABS‐based gears reinforced by different amounts of milled E‐glass fibers and 3D printed by FDM with acceptable thermo‐mechanical properties and performance. A set of thermo‐mechanical tests is carried out to provide an insight into the influence of adding glass fibers on the glass transition temperature (Tg), hardness and teeth bending strength, teeth failure force, weight lost, abrasion resistance, mechanical wear, and performance of composite gears. The mechanical behaviors of driving and driven gears are examined in high and room temperatures with or without lubrication. Microstructure and gear profile analysis of 3D printed layers, worn surfaces, and fracture locations are also conducted by SEM images and profile projector. The newly developed glass fiber reinforced ABS gears reveal a high level of thermo‐mechanical performance in terms of hardness, mechanical strength, bending force, abrasion and wear resistance compared to pure 3D printed ABS gears.

Abstract In this paper, the stamp forming process of a U-shaped cross-section channel with sharp corners of composite laminates including aluminum sheet and polyvinyl chloride (PVC) reinforced with 3D-fiberglass was investigated. The laminates were produced by manual layup and arrangement of fibers with different angles of [0°/90°] and [± 45°] degrees using hot press. The process of forming composite samples was carried out at temperatures of 25, 80, 120, 160°C and different velocities of punch. The effect of parameters including layup configuration, temperature, and forming speed on the spring-back of the formed laminates and the required forming force were evaluated. The results showed that as the forming temperature increased, the forming force decreased sharply. The lowest forming force was obtained for the laminate with [± 45°, Al, ± 45°] layout at 160°C temperature which was equal to 0.7KN. Also, with the increase in temperature, the spring-back angle has been reduced, the lowest of which is obtained with the laminate with [0°/90°] 3 layout equal to 8 degrees. Finally, it was concluded that increasing the speed of the forming process results in a decrease in the spring-back angle and this effect is more pronounced at higher temperatures. Graphical abstract

The present study aims to implement a non-destructive approach to determine the tensile properties of magnesium-based nanocomposites reinforced with ZrO2 and TiO2 nanoparticles. Micron-sized magnesium particles were blended with 0, 1.5, 3, and 5 volume percentage of ZrO2 and TiO2 nanoparticles and hot-pressed at 450 °C under the pressure of 600 MPa. Next, the spherical indentation test was performed on the produced composites to obtain the load–penetration curves. A finite element model of the indentation test was then developed using the Hollomon material model with randomly chosen materials constants. At the next stage, load–penetration curves were obtained for each composite using simulations. A Levenberg–Marquardt neural network was then trained and utilized to find the correct material constants by minimizing the differences between the experimental and simulated load–penetration curves. The results indicated that there is a linear relationship between the tensile strength and content of the reinforcement phase, while it is inversely proportional to the size of the reinforcing particles. Magnesium composites reinforced with 5 volume percentage of ZrO2 and TiO2 nanoparticles showed tensile strengths 2.5 and 2.1 times greater than that of unreinforced magnesium, respectively. It was shown that the proposed method is able to calculate the tensile properties of magnesium-based composites in an accurate and inexpensive manner.

Resin tubes made of epoxy base material and fibers are widely used in the transportation, and aeronautics industries due to their high mechanical properties. Different reinforcing fibers and resins are usually used in making these tubes and lead to various properties. In this study, tubes made by using a 45-degree unilateral winding method and reinforced by Glass, Carbon, and Kevlar fibers and their hardness and wear behaviors were investigated. The results showed that the highest hardness was obtained for the carbon fiber reinforced composite tube (CFR), equal to 65HV, which was 109% more than the Kevlar fiber reinforced composite tube (KFR). Higher hardness indicates greater resistance of the material to local deformation and also stronger bonding between the base material and the reinforcing fibers. The wear test results showed that the wear rate of CFR was 6 mg/m, which was 26% and 55% lower than the glass fiber reinforced composite tube (GFR) and KFR, respectively. The obtained result can be explained as a result of good bonding and compatibility between carbon fibers and used resin. Scanning electron microscope (SEM) images were taken to evaluate the results.

Due to the lightness, Magnesium is one of the most applied metals in the automotive and aerospace industries. Mechanical and tribology properties of Mg and its alloys can be enhanced through the addition of reinforcement materials. In this study, the effect of double-action compaction was investigated on the relative density, hardness, compressive strength and wear behavior, of Mg-based nanocomposite reinforced with the different volume fraction of WO3 nanoparticle. The nanocomposite powders were double-action compacted at different pressures including (300, 500, 700 MPa) and then sintered in a furnace under argon gas at 450 °C for 1 h. Specimens with a relative density above 90% were produced through this method. Relative density increased with increasing pressure in all samples. Also, the highest relative density of the compressed Mg-1.5 vol.% WO3 sample at 700 MPa pressure was about 4.14% higher than that of the compressed same sample at pressure (300 MPa). The highest hardness was obtained for Mg-5 vol.% WO3, which is 29% more than pure Mg. In addition, the compressive strength of Mg-1.5 vol.% WO3 nanocomposite was about 45% higher than that of the pure Mg. An Improvement in strength was obtained due to strengthening mechanisms such as the Orowan mechanism and an increase in dislocation density due to the thermal mismatch phenomenon created duration compaction. Moreover, the lowest wear rate for Mg-5 vol.% WO3 nanocomposite was 3.82 (10−6 × cm3/N.m) which was 67% higher than pure Mg. The SEM analysis of worn surfaces of the specimens showed that the adhesion, abrasive, and delamination were the dominant wear mechanisms. Keywords: Nanocomposite, Magnesium, Double-action compaction, Mechanical properties

This work compares the performance of optical lenses made of silica glass or borosilicate glass (BK-7) when submitted to high-flux radiation emitted by a xenon arc lamp or provided by a high-concentration solar tower. Each irradiation test lasted for 60 min, with continuous monitoring of the radiation-flux incident on the lenses and the temperature generated in their vicinity. All silica glass lenses showed a good performance with both irradiation sources, xenon arc lamp and natural solar radiation, contrary to what was observed with the lenses made of borosilicate glass which fractured when irradiated with a xenon arc lamp. The negative behavior observed with the borosilicate lenses is attributed to the fact that the radiation spectrum of a xenon arc lamp contains certain wavelengths, in the near ultraviolet (UV) region, that are not present in the natural solar radiation spectrum at sea level.

Solar radiation homogenizers are multi-mirror devices that try to reshape the solar radiation distribution coming from a concentrator, so that, after passing through the homogenizer, the light flux becomes as much evenly distributed as possible. The optical behavior of these multi-reflective devices is complex and still ill-understood. The geometry of the concentrator defines the features of the concentrated flux and then the characteristics of a particular homogenizer must be chosen according to the envisaged use. In this work, we developed and used optical ray-tracing software to investigate how the homogenizer’s optical output is affected by the following homogenizer’s characteristics: (i) Number of reflecting surfaces; (ii) total length; (iii) position (relative to focal plane); and (iv) tilt angle (inclination) of reflecting surfaces. The obtained results provide valuable information for the use of these optical devices and may contribute to the development of more efficient strategies for homogenization of concentrated radiation generated by high-flux solar furnaces.

Polymeric tubes, including epoxy and reinforcing fibers, are widely used in the petroleum and aerospace industries due to their high strength and corrosion resistance. In this study, corrosion and creep properties of resin-based tubes reinforced by Glass fibers (GFR), Carbon fibers (CFR), and Kevlar fibers (KFR) were investigated using tubes made by using a 45-degree unilateral winding method. The highest creep strain was obtained for the CFR equal to 0.7445 and the lowest was obtained for KFR with the Kevlar fibers being severely damaged. The lowest corrosion rate per year was for the CFR sample, equal to 113in/year×1000. The corroded samples were subjected to a tensile test and a 2% improvement in ultimate tensile strength was achieved for GFR. To evaluate the results and the quality of adhesions between fibers and resins, SEM images were taken of the samples.

One of the applications of composites is in the manufacturing tubes, which are widely used in industries such as petroleum, petrochemical, and aerospace. Composite tubes are made of thermoset resin base material and reinforced by fibers, having a solid, lightweight, and corrosion-resistant structure, which is a great replacement for metal and concrete tubes. In this research, composite tubes with various resins base material, Swancor901, Epiran-1012, and Epiran-06FL reinforced by different fibers glass, carbon, and kevlar fibers, according to the compatible role, with the angle of 45° and unidirectional and same size, thickness, and diameter, were produced by the winding method. To study the mechanical properties of produced composite tubes, tensile, compressive, and three-point flexural strength tests were performed. The results showed that the highest ultimate tensile strength was obtained for carbon fibers reinforced tube (CFR) equal to 139MPa, which was 136% and 26% higher than kevlar fibers reinforced tube (KFR) and glass fibers reinforced tube (GFR), respectively. The highest flexural strength was also obtained for GFR equal to 91.08MPa, which is 132% and 13% higher than the flexural strength of CFR and KFR, respectively. Also, according to the results of the compression test, the highest compressive strength was observed in the samples reinforced with glass, kevlar, and carbon fibers, respectively. SEM imaging results from the cross-sections show that the best bonding between the base material and the fibers was observed for CFR.

In this research, pure powder of Mg was mixed with 0, 1.5, 3, 5%vol. of Aluminium oxide in a planetary mill. Next, the powder mixture was poured in a mold and pressed in two diverse conditions of (1) hot pressing at 600 MPa pressure and 450 °C temperature for 25 min and (2) cold pressing at 600 MPa pressure in the room temperature and samples sintered in a furnace under Argon gas at 450 °C temperature for 2 h. Density and mechanical properties, e.g., microhardness, and wear properties of the produced samples were assessed. Also, metallographic photography and SEM analysis were done on the samples to investigate their microstructure properties and analyze their worn surfaces. The results revealed that with an increase in the volume of the reinforcement particles, the experimental density and microhardness soared, on the contrary, the relative density showed a decreasing trend. Moreover, the results of the microhardness analysis for the produced samples via hot pressing method were achieved better than those of cold pressing, as the highest hardness 81HV was achieved for %5 vol. Al _2 O _3 containing samples produced through the hot pressing method, which was about %18 more than that of the %5 vol. Al _2 O _3 containing samples produced via the cold pressing method and was about %85 more than of the pure Mg samples produced via the hot pressing method. The results of the samples’ wear properties also signified the improvement of wear resistance and decrease of mass loss with an increase in the volume fraction of the reinforcement particles. The lowest mass loss of 2.5 g was obtained for the sample containing %5 vol. of the reinforcement particle which was produced via the hot pressing method. This value was less about %40 and %80 compared to pure Mg samples produced via hot and cold pressing methods, respectively.

Frozen storage of emulsion-type sausages may be one approach to avoid or reduce the use of sodium nitrite, which is associated with health risks. Silver carp (Hypophthalmichthys molitrix) mince (M0) was washed for 1 (M1) or 3 (M3) times and the impact of washing on the properties frozen storage (−18 °C) during 4 months were determined and results were compared to those of conventional silver carp sausages (Mt). Lipid oxidation, as evidenced by changes in thiobarbituric acid reactive substances and FFAs, took place during storage in the order of M0 > M1 = M3 = Mt with M0 being highly oxidized (P ≤ 0.05). Total volatile base nitrogen formed during storage and the ranking for the quality loss was as follows M0 > M1 > M3 = Mt. Washing (M1 = M3) led to less hardness (P ≤ 0.05). Mt had better redness, while M1 and M3 led to higher expressible moisture, water release and lightness (P ≤ 0.05). Results indicated the lower sensory and consumer-liking properties of frozen M1 and M3 sausages. Therefore, washing and frozen storage influenced silver carp mince sausages.

Abstract The aim of this study was to use apple peel extract (APE) as antioxidant for inhibition of lipid and protein oxidation in rainbow trout (Oncorhynchus mykiss) mince during refrigerated storage. Apple peel extract had high 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobios-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and hydroxyl radical scavenging activity and ferric reducing antioxidant power (FRAP) comparable to ascorbic acid. Lipid oxidation was effectively inhibited in mince during 96 h of refrigerated storage as indicated by significantly lower peroxides and thiobarbituric acid-reactive substances (TBARS) (P