Cold Extrusion Research Articles

Insight into Sequential Extrusion and Cysteine Treatment for Improving Rheological Characteristics and In Vitro Digestibility of Whey Protein Isolate.

The effects of sequential cold extrusion and cysteine (Cys) treatment on the rheological characteristics and in vitro digestibility of whey protein isolate (WPI) were researched in this work. Cold extrusion and Cys treatment increased the apparent viscosity, shear stress, Péclet number, and viscoelasticity of WPI. Furthermore, the emulsifying activity index enhanced in the order of WPI, Cys-treated WPI (Cys-WPI), cold-extruded WPI (CWPI), and extrusion-Cys treated WPI (Cys-CWPI). The emulsion stability index of Cys-CWPI was increased by 29.69% higher than that of WPI. Besides, the α-glucosidase inhibitory rate and xanthine oxidase inhibitory activity in the digests of Cys-CWPI were markedly increased compared with digests of WPI. The synergism of cold extrusion and Cys provides an effective approach for the application of whey protein-based thickeners and emulsifiers; meanwhile, its digestive products may assist in the development of hypoglycemic and uric acid-lowering foods.

Shear tests and meso-scale simulation of cold joint structures in rock-filled concrete: Considering the mutual contact effects between component materials

To realistically reflect the shear performance of the rock-filled concrete (RFC) between layers, this study relies on an RFC dam project in Guizhou Province. Test blocks, measuring 5 m × 4 m × 2 m with cold joints, were cast on site and subjected to shear tests. Additionally, a three-dimensional four-phase meso-model was developed, considering the mutual contact effects between component materials. The mechanical response and damage mechanism of the interlayer were analyzed using the cohesive zone model. The results confirm that the cohesive zone model effectively simulates interlayer cold joint structures. The damage modes of the RFC interlayer include cold joint debonding damage (Mode I) and plastic extrusion damage of self-compacting concrete (Mode II). As the exposed height of the rocks increases, the damage mode shifts from Mode I to Mode II, and higher normal stresses intensify Mode II damage. Meanwhile, the paths of crack extension depend on the distribution of shear-resistant rocks, with weak interfacial transition zones serving as “bridges’’ for crack propagation. The interlayer shear strength is positively correlated with the average exposed height of rocks and normal stresses, with the former having a more significant impact. Finally, the accuracy of the proposed shear strength prediction model for the RFC interlayer was validated by comparing it with results from other studies, providing useful references for meso-numerical modeling of RFC.

Effects of the extrusion process on the physical properties of micro pellets and the growth performance of juvenile Nile tilapia

The present study aimed to evaluate the effect of different extrusion processes on the physical properties of micro pellets and how the alterations affect the growth performance of juvenile Nile tilapia. Four experimental diets were produced with the same formulation, but with different extrusion processes: CE: cold extrusion (18 ºC); HE: hot extrusion (100 ºC); D1: double extrusion, first a hot extrusion (100 ºC) of all the ingredients followed by cold extrusion (18 ºC); D2: double extrusion, first a hot extrusion (100 ºC) of the plant-based ingredients followed by mixing with the animal-based ingredients and milling, then cold extrusion (18 ºC). Juvenile tilapia (0.83 ± 0.01 g; 3.68 ± 0.19 cm) were distributed in 20 experimental units (60 L; n=5; 20 fish per unit) in a completely randomized design for four weeks. The micro pellets of the experimental HE diet presented a positive expansion rate (2.86 ± 0.45 %) and a lower bulk density (465.9 ± 3.45 g/L). The D1 and D2 micro pellets presented higher bulk density (671.0 ± 2.98 and 612.8 ± 4.99 g/L, respectively). All the micro pellets showed high durability (>95 %). The D2 micro pellets showed low water resistance (24.4 ± 3.51 %), resulting in a high leaching rate of nutrients (>68 %). The HE and D1 micro pellets showed a higher absorption rate in water (3.65 ± 0.29 and 3.66 ± 0.21 g water/g, respectively). The water solubility index of the micro pellets was not influenced by the different extrusion processes (P > 0.05), nor were survival and feed consumption. The fish fed with the HE diet showed greater weight gain (3.84 ± 0.44 g), and the lowest weight gain was in the fish fed with the CE diet (3.05 ± 0.39 g) (P < 0.05). Feed conversion was lower in fish fed the HE (1.06) and D1 (1.11) diets (P < 0.05). Fish fed the HE diet had the highest values for relative growth rate (9.08 ± 0.62 %/d), protein retention (30.6 ± 2.61 %) and protein efficiency (2.26 ± 0.22 %) (P < 0.05). Fish fed the CE diet had the lowest values for relative growth rate (7.82 ± 0.51 %/d), protein retention (21.4 ± 2.72 %) and protein efficiency (1.55 ± 0.23 %) (P < 0.05), though the values are in line with those in the literature. In conclusion, hot extrusion resulted in micro pellets with better physical properties and fish with higher growth performance. Double extrusion, first a hot extrusion of the plant-based ingredients followed by mixing with the animal-based ingredients and milling, then cold extrusion is not recommended due to high levels of nutrient leaching. Cold extrusion and double extrusion, first a hot extrusion of all the ingredients followed by cold extrusion processing can be considered for producing micro diets for juvenile tilapia, especially when less investment in the extrusion process is desired.

Investigation into cold extrusion preforming of tantalum alloy component using finite element method

Investigation into cold extrusion preforming of tantalum alloy component using finite element method

Multi-objective collaborative optimization of internal thread cold extrusion process based on response surface method

Multi-objective collaborative optimization of internal thread cold extrusion process based on response surface method

Examination of the Impact of suitable Process Parameters on the Cold Extrusion of AA5754

Examination of the Impact of suitable Process Parameters on the Cold Extrusion of AA5754

Effect of Extrusion Temperature on Microstructure and Mechanical Properties of Mg–Al–Zn Alloy Prepared by Solid‐State Recycling of Mixed Waste Chips

The recycled Mg–Al–Zn alloys are successfully fabricated through solid‐state recycling of mixed waste chips, including cold pressing and hot extrusion. The effects of extrusion temperature on the microstructure evolution, slip mode, tensile properties, and hardness are studied. The homogeneous fine dynamic recrystallization (DRXed) grains with an average grain size of less than 13.1 μm can be obtained at four different extrusion temperatures (250, 300, 350, and 400 °C). The average grain size of the DRXed grains continuously increases with the rising extrusion temperature. However, the yield strength (YS), ultimate tensile strength (UTS), and elongation to failure (EL) of the recycled alloys increase first and then decrease. The recycled Mg–Al–Zn alloys at 350 °C demonstrate excellent mechanical properties with the YS of 134.6 MPa, UTS of 286.2 MPa, EL of 7.4%, and Vickers hardness of 75.2 HV, respectively. In addition, the slip mode is transformed from the previous basal slip to the coactivation of multiple slips composed of the basal slip, prismatic slip, and pyramidal slip with the rising extrusion temperature.

ВПЛИВ КІЛЬЦЕВИХ КАНАВОК ХОЛОДНОГО ОБТИСКУ НА ДОВГОВІЧНІСТЬ ПАНЕЛЕЙ КРИЛА З ФУНКЦІОНАЛЬНИМИ ОТВОРАМИ

This article studies in detail the method of cold extrusion annular grooves to solve the problem of aircraft fatigue life extension that reduces the fatigue life of aircraft wing panels due to functional holes. This method is a very simple and effective anti-fatigue manufacturing technology. In order to simulate the different wing panels with functional holes, the experiment is designed to extrude the specimen with different extrusion forces to obtain annular grooves of different depths. Fatigue tests are conducted on specimens with annular grooves. The test results show that: 1) Cold extrusion annular grooves can extend the fatigue life of wing panels with functional holes; 2) The fatigue life of wing panels with functional holes is affected by the depth of the cold extrusion annular groove. The fatigue life changes in an inverted "V" shape as the depth of the cold extrusion annular groove increases; 3) When cold extrusion annular groove depth is 0.26mm, the fatigue life of specimen with holes is maximum, and the fatigue life is increased by 2.35~32.9 times when specimen thickness is 5 mm

Multi-gradient structures by cold extrusion of strongly textured continuously cast commercially pure aluminum

During extrusion, the material is subjected to a heterogeneous deformation that results in the formation of gradients of microstructure and thus mechanical properties. In this study, using continuously cast commercially pure aluminum as a reference material, we show how a cast structure with coarse columnar grains affects the formation of these gradients during extrusion at room temperature. Characterization of the initial material as well as the extruded round bars by optical and electron microscopy, X-ray diffraction as well as by means of mechanical testing documents the formation of four characteristic annular sections. For extrusion along the casting direction there is a <100>/<111> double-fiber textured center with lowest hardness, followed by a <111> single-fiber textured ring with a hardness plateau, a double-fiber textured region with grains arranged alternatingly in an iris-like shape, and an (ultra-)fine grained surface layer with highest hardness. For extrusion opposite to the casting direction we find similar characteristics of the center section. With increasing distance from the center follow another double-fiber textured section with increasing hardness, a <111> single-fiber textured ring with nearly homogeneous hardness and a surface layer with a slightly rotated <111> fiber and highest hardness. The key finding is that the macroscopic anisotropy of the cast material, resulting from the grain size, crystal orientation and growth direction of the columnar grains, determines the local material flow during extrusion and thus leads to the formation of these different complex multi-gradient macrostructures that may provide unique properties for complex applications such as light-weight safety-relevant components.

Parametric Study for Damage Optimization in Two-Stage Cold Extrusion Dies by Implementing Taguchi Method and ANN Method in Genetic Algorithm

Parametric Study for Damage Optimization in Two-Stage Cold Extrusion Dies by Implementing Taguchi Method and ANN Method in Genetic Algorithm

Processing Techniques and Metallurgical Perspectives and Their Potential Correlation in Aluminum Bottle Manufacturing for Sustainable Packaging Solutions

This study explores the potential of aluminum wine bottles as a sustainable alternative to traditional glass bottles, emphasizing their recyclability and environmental advantages. It reviews the potential use of Al-Mn-Mg 3xxx alloys in beverage can bodies and examines various applications of aluminum containers in packaging, including recyclable beverage containers. The manufacturing processes for aluminum bottles, including casting, rolling, punching, and deformation techniques, are discussed in detail, with a particular focus on their impact on mechanical properties and microstructure. The preference for 1xxx aluminum alloys in impact extrusion is explained, highlighting their lower flow stress and higher formability compared to 3xxx alloys, and the microstructural changes induced by various processing steps are analyzed. Challenges related to using recycled aluminum and their effects on mechanical properties and microstructure during aluminum bottle production are also addressed. One objective is to increase the proportion of recycled alloyed material used in aluminum bottle manufacturing. Depending on the technique employed, the fraction of alloyed recycled material can vary. The percentage of recycled alloyed material (3xxx series Al alloys) in cold backward impact extrusion could be raised by 60%. High-speed blow forming could facilitate the production of aluminum bottles with a recycled alloyed material ranging from 50 to 100% of the 3xxx series aluminum can body alloys. The high-speed drawing and ironing (DWI) process can produce large-format aluminum bottles (up to 750 mL), utilizing at least 90% of the recycled 3xxx series can body stock. Furthermore, the paper discusses the importance of optimized heat treatment designs in enhancing mechanical properties and controlling microstructural evolution in alloyed aluminum materials, such as 3xxx series alloys. The study concludes with a need for further research to deepen our understanding of the metallurgical aspects of aluminum bottle manufacturing and to optimize the use of recycled aluminum in packaging solutions, with a specific focus on improving mechanical properties and microstructural integrity. This comprehensive review aims to contribute to the development of more sustainable packaging practices in the beverage industry by providing insights into the interplay between manufacturing processes, mechanical properties, and microstructure of aluminum bottles.

Numerical simulation on the dynamic cold extrusion of bolted single-lap Al/Al joint under interference-fit

The installation process for the dynamic cold extrusion of Al/Al interference-fit bolted joint applied by electromagnetic force was investigated by numerical simulation. The simulation results show that the deformation distribution of the bore wall at joint installed by the electromagnetic force is more uniform than that of the traditional installation technologies. And in the axial direction of bore wall without pin, the maximum stress region occurs at its outlet regardless of the values of interference-fit. Additionally found that the critical interference-fit value for a joint to reach yield strength is about 1 %, and when the amount of interference-fit is less than 1%, the joint mainly exhibits elastic deformation, and when the interference is more than 1 %, the plastic deformation is its main manifestation.

Quality attributes of pasta produced from cassava starch, egg powder and spiced with ginger flour

Protein malnutrition stands out as the most serious nutrition deficiency problem in infants and young children in developing countries. This study investigated the quality attributes of pasta produced from a blend of cassava starch, egg powder, and ginger flour. D-optimal mixture design approach was used for the formulation of the flour blends, resulting into fourteen experimental runs. Pasta was manufactured from this blend via cold extrusion process and was analyzed for proximate composition, colour, antioxidant, cooking and sensory properties using standard methods. The crude protein and total carbohydrate contents of the pasta ranged from 4.15-8.40% and 81.29-86.28%, respectively. Significant differences (p&lt;0.05) were observed, from a statistical viewpoint, in the colour and antioxidant properties. The cooking properties ranged from 8.45-20.07min, 2.88-20.00%, 1.06-8.47% and 86.50-468.74% for cooking time, cooking loss, expansion ratio and water absorption capacity, respectively. However, pasta produced from cassava starch, egg powder and ginger flour were all preferred by the panelists in terms of aroma, colour, texture and appearance, but pasta from the control sample had the highest overall acceptability. The study showed that pasta from cassava starch, egg powder and ginger flour could be useful to combat malnutrition and nutritional deficiencies in developing countries.

Analysis of the influence of dies geometry on the process extrusion force and properties of the extrudate obtained in the process of cold extrusion of 7075 aluminum alloy by the KOBO method

Abstract The KOBO extrusion process is an unconventional method of extrusion based on the phenomenon of superplasticity as an effect of a special state caused by the oscillatory motion of the die at a certain angle a certain frequency. It significantly lowers the extrusion force and makes it possible to extrude lightweight metals and alloys (e.g. aluminum and magnesium alloys) in cold extrusion with high extrusion ratios compared to conventional hot extrusion. This work studies the influence of the tool (die) geometry on process realization parameters and the properties of the extrudate. Experimental studies of cold KOBO extrusion were performed using dies with different face portion geometry. The obtained extrudate obtained from EN-AW 7075 aluminum billets was examined for mechanical properties and macro/microstructure, showing that, with adequate modifications to the tool face part geometry, it is possible to lower the extrusion force and obtain extrudate with desired properties.

Bearing capacity of horizontal joints of UHPC prefabricated shear walls with vertical bars splicing by cold-extrusion sleeves

To study the shear performance of the horizontal joints of ultra-high-performance concrete (UHPC) prefabricated shear walls with vertical bars splicing by cold-extrusion sleeves, unidirectional loading tests for three samples have been conducted and a method to calculate the shear bearing capacity of the horizontal joint has been proposed. The influence of the reinforcement ratio and axial compression ratio on failure mode, cracking morphology, load-displacement curve, and shear bearing capacity of the horizontal joints has been analyzed in the tests. In addition, the failure process of the three samples has been simulated using finite element method. The results showed good agreement between the test results and numerical results, which certified the validity of the proposed calculation method for the shear capacity of the horizontal joint. The test results showed that the cold extrusion sleeve connection can effectively transmit the stress of the reinforcement, and the shear bearing capacity of the horizontal joints of the UHPC prefabricated shear wall can be enhanced by increasing the axial compression and reinforcement ratios.

3D printed sweets made with peanut chenna and milk: A new frontier in food technology

AbstractThe recent development of three‐dimensional (3D) food printing technology is having an important impact on the food processing sector. This cutting‐edge method permits the manufacturing of foods with outstanding customization in terms of both look and nutritional profile. Several methods have been applied to demonstrate how 3D printing can be adopted in the food processing sector. These methods include selective laser sintering, hot‐melt extrusion, and inkjet printing. In contrast, high‐temperature techniques are not appropriate for constructing 3D representations of nutrients that are sensitive to changes in temperature. Cold extrusion is an effective alternative approach for 3D printing; however, its successful implementation requires the inclusion of rheology substitutes and the careful standardization of different elements involved in the process. In order to overcome this constraint, we utilized the technique of direct ink writing for 3D printing of the product by cold‐extrusion. This was achieved by using a combination for the different material formulations. This research provides confirmation on the feasibility of using 3D printing technology to print peanut based chenna, with the incorporation of skim milk (SM) powder, while maintaining a minimal material formulation. The flow properties of printing material compositions can be accurately explained with the R2 &gt; 0.996 Power‐law and Herschel–Bulkley model. The flow behavior index, denoted as n, (n &lt; 1), suggesting that the fluid exhibits shear thinning properties. The value of the loss modulus (G″) for material formulation was significantly lower than that of the storage modulus (G′). It was found that the storage modulus and the viscous modulus both emerged higher with increasing angular frequency. The formulation of the material, with its higher storage modulus indicating better durability, enables printing of a broad spectrum of food items. The primary objective of this study was to investigate the enhancement of printability in food compositions through the utilization of peanut‐based chenna. In order to achieve consistent and accurate results at different ratios (1:1, 2:1, and 3:1, w/w), a comprehensive evaluation was conducted on several printing parameters. These parameters included printing formulations, height of the nozzle, diameter, or size of nozzle, printing rate of speed, extrusion motor speed, and rate of extrusion. The extrusion printing parameters were adjusted to achieve optimal printing conditions for a 2:1 composition of SM powder and peanut‐based chenna. These parameters included the height of nozzle (0.314 mm), size of nozzle (0.4 mm), printing speed (30 mm/s), extrusion rate (5.21 mm3/s), extrusion motor speed (240 rpm), and extruder pressure (5 bar).Practical applicationsThe emergence of food printing is a game‐changer for the culinary world. 3D food printing has expanded the creative options available to chefs, bakers, and entrepreneurs in the food industry by making it possible to print unique and complex designs directly onto edible substrates. In this research, we looked into the material compositions, time standardization, extrusion rate, printing speed, and rheological properties of a food formulations. The present research uses a 3D food printer to explore the unexplored possibilities of a combination of peanut‐based chenna and SM for the purpose of product development.

Optimization analysis of cold extrusion process parameters for valve screws

This study focuses on valve screws and establishes a cold extrusion simulation model using DEFORM-3D software to analyze the deformation characteristics and influencing factors during the extrusion process. Supported by the theory of rigid-plastic finite element, an orthogonal experimental design is conducted to establish a four-factor three-level simulation scheme with general fillet radius, die clearance, extrusion speed, and friction coefficient as the simulation variables, and maximum equivalent stress on the convex die, forming damage of the blank, and maximum wear depth on the concave die as the objective values. The prediction model based on BP neural network algorithm and orthogonal experimental data shows high accuracy. The optimization problem is simplified into a dimensionless numerical analysis problem using GC grey correlation analysis, and the optimal solutions within each variable range are determined using range analysis. The simulation results after optimization show a 20 5% reduction in maximum equivalent stress on the convex die compared to the original scheme, a 4.9% reduction in forming damage of the extruded part, and a 24.24% reduction in maximum wear depth on the concave die compared to before optimization. The actual verification confirms the good forming effect of valve screw extrusion, with well-formed contours and a uniform surface without wrinkles or defects. Finite element simulation provides valuable guidance for practical production.

Cold extrusion of a shaped charge liner preform with hyperboloid structure: simulation and experiment

Cold extrusion of a shaped charge liner preform with hyperboloid structure: simulation and experiment

Experimental and numerical investigations on fatigue behavior of 42CrMo4 high-strength steel single lap double-bolted joints

Cold extrusion forming is a manufacturing technology that effectively extends the fatigue life of mechanical structures and has been widely used in the processing of ship components. The fatigue behavior of 42CrMo4 high-strength single lap double bolted joints is investigated based on fatigue experiment and numerical simulation. The stress-strain distribution of joint plates under cold extrusion, bolted tightening and longitudinal external loads are evaluated based on the nonlinear finite element software ABAQUS. The fractographic of fatigue specimens is detected by scanning electron microscopy (SEM) to research the initiation location and propagation type of fatigue cracks, and a prediction method for the stiffness of joint plate bolt connections is further proposed. The results indicate that fatigue cracks propagated tortuously and exhibits a more complex distribution state. The combination of cold extrusion forming and bolt preload can effectively improve the fatigue life of high-locked bolted joints. Smooth surface, beneficial residual stress field and cold extrusion hardening phenomenon are considered the main reasons for improving fatigue life.

Comparison of the specific mechanical energy, specific thermal energy, and functional properties of cold and hot extruded pea protein isolate

Pea protein is a popular source of plant-based protein, though its application in meat and dairy analog products is still lacking. This is particularly true in the development of products with fatty and creamy textures. Cold denaturation may be a way to induce these types of textures in food since this is a universal phenomenon in protein that occurs due to a weakening of hydrophobic interactions at cold temperatures. This work utilizes a single screw extruder to systematically study the impacts of moisture content (50–65 %) and pH (2,4.5,8) on the outlet temperatures, specific mechanical energy, specific thermal energy, and texture of cold-extruded pea protein. It was found that at pH 2 and moistures of 60 % and greater, the temperature of the product exiting the extruder is <5.5 °C, and also produced 13.7 %–36.5 % more specific thermal energy, indicating the occurrence of cold denaturation in these products. Based on these findings, a comparison of hot and cold extrusion was conducted as a function of pH and oil content. It was found that cold extrusion imparts 43.0 %–56.2 % more mechanical energy into the protein than hot extrusion, and the cold extruded protein had higher values of Young’s modulus and breaking stress. The protein extruded at low temperatures was also able to bind 32.93 % more oil than hot extruded proteins when extruded with 10 % added oil, which may aid in the formation of protein-based fat memetics for the food industry.