Injection Moulding Method Research Articles

Effect of fly ash on mechanical properties and microstructural behaviour of injected moulded recycled polypropylene composites

The global challenges of plastic waste and fly ash accumulation demand innovative recycling solutions. In Malaysia, the consumption of 11.2 million tonnes of coal annually generates approximately 2 million tonnes of fly ash, while the recycling of Polypropylene (PP) is hindered by thermo-oxidative and shear-induced degradation during mechanical recycling, resulting in reduced mechanical properties. This study addresses these issues by fabricating recycled PP composites incorporating varying fly ash contents, using a single cycle of mechanical recycling with extrusion and injection moulding methods. The composites were comprehensively tested for tensile, flexural, and compressive strengths, as well as microstructural behaviour. The results reveal a complex relationship between fly ash content and mechanical performance: while tensile strength decreases with increasing fly ash, flexural strength and strain peak at 5 % and 9 % fly ash, respectively. Compressive strength also shows a slight increase up to 7 % fly ash, indicating an optimal range for enhancing mechanical performance. Furthermore, mathematical models were proposed to predict the mechanical properties of rPP – fly ash composites, providing a valuable tool for future material design. These findings demonstrate that optimization of fly ash content can mitigate the effects of polymer degradation, offering a sustainable solution to improving the mechanical performance of this composite.

Chemical treatment, fibre length, and fibre loading affecting the mechanical and morphological characteristics of flax fibre/polylactic acid (PLA) green composites developed by injection moulding

AbstractThis paper presents the parametric investigation and optimization of various chemical treatment parameters that affect the mechanical performance of the green composite. The injection moulding method was used to produce the green composites using flax fibre (FF) and polylactic acid (PLA). The chemical parameters chosen to investigate their effects are chemical type (sodium hydroxide, sodium carbonate, and potassium hydroxide), chemical concentrations (1 %, 2 %, and 3 % (w/v)), and duration for fibre treatment (2 h, 4 h, and 6 h). The mechanical performance of the green composites was assessed by evaluating the various properties namely strength, modulus, and elongation under tensile, share, flexural, and compression loading conditions. The morphological study was also performed to examine the failure behavior of the composite after mechanical testing. The effect of fibre length (2 mm, 3 mm, 4 mm, 5 mm, and 6 mm) and fibre loading (10 wt.%, 20 wt.%, and 30 wt.%) on the performance of the flax fibre (FF)/polylactic acid (PLA) composite was also investigated. The fibre dispersion, fibre orientation, and fibre length retention were investigated to assess the characteristics of fibre during injection moulding of the developed flax fibre (FF)/polylactic acid (PLA) composite.

Fabrication of Translucent and Chemically Durable Crystal‐Glass Composite with Multicolor Persistent Luminescence

AbstractLong persistent luminescence materials (LPLMs) are promising candidates for various photonic applications, owing to their ability to store light. In spite of advancements in exploring of new LPLMs, the fabrication of transparent centimeter‐sized LPLMs with pre‐designed shapes, high productivity, long afterglow multicolor luminescence, and high chemical stability, is still challenging. Here, high‐throughput manufacture of translucent crystal‐glass composites via a classical injection molding (IM) technique is demonstrated, in which persistent phosphors (PPs)‐amorphous silica nanoparticles‐polymer composites are molded into different shapes then thermally treated at elevated temperatures to obtain glass composites with embedded PP particles and customized shapes. The structural characterizations endorse that the PP particles are preserved during high temperature sintering, and the resultant crystal‐glass composites combine the unique benefits of both PPs and silica glass. Remarkably, the total production time to manufacture 100 pieces of centimeter‐sized crystal‐glass composites is 35 h, thus enabling high‐throughput production of glass composite articles by the IM method. In addition, the injection molded crystal‐glass composites demonstrate long afterglow multicolor luminescence and ultrahigh chemical durability. This study provides a massive production strategy for the fabrication of translucent and stable multicolor persistent luminescent objects with customized shapes, which can be used in numerous applications.

Silica-based ceramic cores for high-pressure turbine airfoil blades in aircraft engines

Ceramic cores for high-pressure turbine airfoil blades in aircraft engines are characterised by very complicated shapes and the presence of small diameter holes and thin long grooves. In this paper, eight starting powder mixtures having different contents of fused silica, zirconium silicate, alumina and borosilicate glass were used for preparation of core material. The composition, which satisfies every demand for core application in the investment casting of high-pressure turbine blades, contains 69.0wt.% fused silica, 13.0 wt.% zirconium silicate, 12.0wt.% alumina and 6.0wt.% borosilicate glass. This material was characterised by a mechanical strength of 33.1MPa, a coefficient of thermal expansion of 2.56 ? 10?6 1/K, surface roughness of 1.8 ?m, shrinkage of less than 0.8% and an average pore size diameter of 2.7 ?m. The thin-walled ceramic cores were formed by the high-pressure injection moulding method, which required the selection of a thermoplasticiser, feedstock formulation and determination of the optimal processing conditions protecting the injected cores from defects and deformation. The post-shaping process of the cores included both water and thermal debinding, sintering, precision machining and dimension measurements.

Preparation and characterization of all-particle SiC ceramic filters

All-particle porous SiC ceramic filters were prepared by injection moulding and pressureless sintering methods. All-particle porous SiC ceramic filters were successfully prepared by using 1 mm SiC large particles as the main raw material and alcohol solutions of Al2TiO5, MgO, CeO2 and Polyvinyl Butyral (PVB) as slurry. Highly pure Al2TiO5 was successfully prepared at 1600 °C and a holding time of 2 h. The effect of the PVB content of the paste on the morphology and properties of the samples after demoulding was investigated. The effects of sintering temperature, holding time, MgO content, and CeO2 content on the mechanical properties of all-particle porous SiC ceramic filters were discussed. It was finally determined that 69 wt% of Al2TiO5, 6 wt% of MgO, 3 wt% of CeO2, and 2 wt% of PVB was the best performance of the samples. The experimental results show that the final sintering temperature for all-particle porous SiC ceramic filters was 1400 °C and the holding time was 20 min. At this time, the flexural strength, apparent porosity, and density of the sample were 6.6788 MPa, 42.1242 %, and 1.8319 g cm−3, respectively.

Influence of alumina powder (Al2O3) on mechanical and tribological properties of injection molded polyoxymethylene composites

Composite materials combine two or more materials with mechanical and chemical properties that differ from one another. The matrix is one element, while the reinforcement is another. In this study, alumina powder (Al2O3) is used as filler while polyoxymethylene (POM) is used as the matrix. The injection moulding method is used to produce the composite specimens in this investigation. Prior to injection moulding, composite pellets are made using a twin-screw extruder. Compounding is done to produce a homogeneous mixture. The injection moulding method is the most efficient solution for mass-producing material with the slightest faults in samples. The advantage of injection moulding is that it only takes a few minutes to complete a cycle.The composite was put through mechanical, tribological, and morphological testing as part of this investigation to determine its strength. Tensile, flexural, and compression tests are examples of mechanical tests. A wear test is conducted with the help of a pin-on-disc setup. The specific wear rate of all the samples is calculated. The SEM is done to study the surface of the sample after the tensile test. From the tensile test, it is found that with the increase in the amount of tensile strength of composite decreases. The maximum flexural strength (180.92 N/mm2) is obtained for a sample with 1% of alumina powder. The maximum compression strength (91.88 N/mm2) is achieved for a sample with 4% of alumina powder. The SEM image shows the brittle failure of a composite.

A Structural Design of the Injection Mould

This paper proposes the design of an injection mould for a lightning frame. A challenging area in the field of the injection moulding process is undoubtedly the correct design of the injection mould. The injection moulding method has received much attention in recent years due to the mass production of plastic components with complex shapes and exacting dimensional specifications. Advantageous features of injection moulding are high repeatability and precision paired with speed, a cheap cost per item, and a wide variety of plastics. The software program used to design the injection mould and simulate its functionality was Autodesk Inventor. The result of this paper is to extend our knowledge of injection mould construction.

An Injecting Molding Method for Forming the HFRP/PA6 Composite Parts.

Carbon/glass fiber-reinforced polymer hybrid composite (HFRP) has the advantages of a light weight and high strength. For the lightweight design of automobile parts, composite parts made of HFRP and polymer materials are increasingly in demand. The method of the injection molding is usually adopted to fabricate composite part with HFRP and polymer materials. The connecting strength between the two materials has an important influence on the service life of the composite part. In this paper, HFRP and polyamide-6 (PA6) were used to fabricate a composite part by the injection molding method. In order to improve the connecting strength between HFRP and PA6, a kind of micro-grooves was fabricated on the HFRP surface. The micro-grooves on the surface of the HFRP provided sufficient adhesion and infiltrating space of molten PA6 material into the mold. In addition, the glass fiber in HFRP can also be used as nucleating agent to facilitate the rapid crystallization of PA6. The micro-grooves on the surface of HFRP were embedded into PA6 like nails, which could improve the connecting strength at the interface effectively. The paper investigated the effects of mold temperature, injection pressure, holding pressure and holding time on the injection quality and connecting strength of composite parts in detail. With a mold temperature of 240 °C, an injection pressure of 8 MPa, a holding pressure of 8 MPa and a holding time of 3 s, the maximum tensile strength of 10.68 MPa was obtained for the composite part. At the effect of micro-grooves, the tensile strength of the composite part could be increased by 126.27%.

Investigation of Sinterability of WC-Co Component Comprising of AISI 4340 Steel Inserts

In this study, sinterability of WC-9% Co component with AISI 4340 steel insert was investigated using Inserted Powder Injection Molding (IPIM) method. Sintering experiments were performed at temperatures of 1200 °C to 1350 °C with dwell times of 120, 240, 360 min. Defects such as gaps, cracks and macro-porosities were observed in specimens, sintered at temperatures of 1200 °C and 1250 °C for all dwell times. It was proved that sintering temperature of 1350 °C was as high as it caused insert to get deformed and melted. As a result, the optimum sintering temperature and dwell time were determined to be 1300 °C and 240 min, respectively, at which the highest hardness, compression strength, and sintered density were obtained without any defects such as cracks or gaps.

Preparation of polypropylene-based thermally conductive composites via multiple injection compression molding method

With the increasing power consumption of electronic devices, this leads to a huge challenge in terms of heat dissipation. In order to solve the problem of heat dissipation in electronic equipment and to improve the stability and life of electronic equipment. This paper reports polypropylene (PP)/carbon fiber (CF)/Al2O3, PP/CF, PP/CF/SiO2 composites with excellent properties, which are prepared by two different methods: injection molding (IM) and injection compression (IC). The PP/CF/Al2O3 and PP/CF/SiO2 composites contain a constant 5 wt% of Al2O3 and SiO2 fillers. Different processing methods are used to prepare the composites in order to investigate the effect of different processing methods on the mechanical properties and thermal conductivity of the composites. The PP/CF/Al2O3 composite (0.475 W/(m⋅K)) prepared by IC method (6 × 0.5 mm) has good thermal conductivity, 15.90% higher than that of the PP/CF/Al2O3 composite (0.410 W/(m⋅K)) prepared by IM method. In addition, the PP/CF/Al2O3 composite has good mechanical properties (tensile strength and elongation at break are 4.22% and 14.176 MPa respectively). This method of IM has great potential for the continuous production of thermally conductive composites.

The effect of additives on properties of silica-based ceramic cores utilised in fabrication of multivane clusters for turbofan jet engine

Ceramic cores for mapping internal cooling channels in multivane clusters for turbofan jet engine must satisfy rigorous requirements concerning material properties and dimensional precision. The effect of different additives (borosilicate glass, alumina and zirconium silicate) on features of silica-based ceramic cores was investigated. The elaborated in this paper material for cores fabrication composed of 64.0 wt% quartz glass, 11.0 wt% borosilicate glass, 13.0 wt% zirconium silicate and 12.0 wt% alumina reveals mechanical strength equal to 25.8 MPa, coefficient of thermal expansion of 3.52 . 10 −6 1/K , surface roughness equal to 2.3 μm, shrinkage less than 1.9% and average pore size diameter of 4.8 μm. The thin-walled long ceramic cores were shaped by the high-pressure injection moulding method, which covered the choice of a thermoplasticizer, feedstock development and determination of the processing parameters protecting the formed cores from imperfection and deformation. The after-shaping process of cores manufacturing included water and thermal debinding, sintering and dimension measurement. The high dimension accuracy of cores was verified by measurement results made on the coordinate measurement machine.

Evaluation of interbody fusion efficacy and biocompatibility of a polyetheretherketone/calcium silicate/porous tantalum cage in a goat model.

ObjectiveTo evaluate the interbody fusion efficacy and biocompatibility of a graft-free cage made of polyetheretherketone/calcium silicate composite/porous tantalum (PEEK/CS/pTa cage) compared with a PEEK/CS cage with an autogenous bone graft in a goat model.MethodsPEEK/CS/pTa and PEEK/CS cages were prepared through an injection-moulding method. The PEEK/CS composites and porous tantalum were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) mapping. Then, adult goats were chosen for C2/C3 and C3/C4 discectomy via the anterior cervical approach and randomly implanted with PEEK/CS/pTa and PEEK/CS/cages with autogenous bone grafts. The fusion performance and osseointegration of the cages were evaluated by X-ray imaging, magnetic resonance imaging (MRI) scanning, and bone histomorphometry analysis. Moreover, the concentrations of Ca and Si in urine, serum, tissue around the fusion segments and major organs of the goats were determined by inductively coupled plasma–optical emission spectrometry (ICP–OES). Histological observation of major organs of the goats was used to evaluate the biosafety of PEEK/CS/pTa and PEEK/CS cages.ResultsX-ray and MRI imaging suggested that both PEEK/CS/pTa cages and PEEK/CS cages maintained similar average intervertebral space heights. The tissue volumes in the fusion area were comparable between the two groups of cages at 26 weeks after surgery. Histological morphometric data showed that PEEK/CS/pTa cages and PEEK/CS cages with autogenous bone grafts had similar bone contact and osseointegration at 12 and 26 weeks. Element determination of serum, urine, spinal cord, dura matter, bone and organs showed that the CS/PEEK cages did not cause abnormal systemic metabolism or accumulation of calcium and silicon in local tissues and major organs of goats after implantation. No obvious pathological changes were found in the heart, liver, spleen, liver or kidney tissues.ConclusionOverall, these results suggested that the graft-free PEEK/CS/pTa cage showed similar bony fusion performance to the PEEK/CS cages with autogenous bone grafts. The cages releasing calcium and silicon had good biological safety in vivo.The translational potential of this article: This study provided a new graft-free interbody fusion solution to patients with degenerative disc diseases, which could avert potential donor-site complications. This study also provided a detailed assessment of element excretion and accumulation of Ca and Si in vivo, which validated the biosafety of this new type of bioactive interbody fusion cage.

A micromechanical approach to elastic modulus of long-term aged chicken feather fibre/poly(lactic acid) biocomposites

Abstract The modulus of elasticity is a critical parameter for the performance design and analysis of biofibre-based biocomposite materials. As a result of criteria such as internal heterogeneity, the random distribution of fibres and the success of interfacial adhesion between the fibre and the matrix, it becomes difficult to predict the modulus of elasticity in practical ways. Therefore, one of the aims of this study is to determine the modulus of elasticity of biocomposite material reinforced with discontinuous and random fibres by means of micromechanical models and experimentally. In addition, it is also aimed to reveal which micromechanical model can be used reliably in predicting the modulus of elasticity of both aged and non-aged biocomposite materials due to the relationship between the analytical and experimental results. In order to achieve these objectives, initially, chicken feather fibre/poly (lactic acid) biocomposite specimens having 2, 5 and 10 % chicken feather fibre mass fractions were mixed and manufactured by extruding, and subsequently, tensile test specimens according to the appropriate standard were formed by the injection-moulding method. An agreement between the moduli of elasticity obtained from 6 micromechanical models and experimentally from the slope of the stress–strain curves resulting from tensile tests was determined.

Quality Improvement of IML Film Injection Molding Method through Structural Analysis

Quality Improvement of IML Film Injection Molding Method through Structural Analysis

INVESTIGATION BEHAVIOR OF POLYMER GEAR MATERIAL

This work primarily focuses on the polymer matrix composite comprising Nylon 6 and Basalt fibre pooled together for the purpose of wear reduction in spur gear material. The method employed here using the Nylon 6 and Basalt fibre is employed through the Injection Moulding method, the fibres are combined in the ratio of (80:20) & (70:30). This project aims to focus on the mechanical properties such as tensile, compression, and impact test as per ASTM standards. Later Finite Element models were then developed to simulate the impact, tensile, and wear characteristics behavior of the tested material,

Comprehensive Areal Geometric Quality Characterisation of Injection Moulded Thermoplastic Gears.

Injection moulding is currently the most widely employed production method for polymer gears. Current standardised gear metrology methods, which are based on metal gear inspection procedures, do not provide the key information regarding the geometric stability of injection moulded gears and are insufficient for a thorough gear inspection. The study developed novel areal quality parameters, along with a so-called moulding runout quality parameter, with a focus on the injection moulding method. The developed parameters were validated on twenty-nine gear samples, produced in the same moulding tool using various processing parameters. The gears were measured using a high-precision structured-light 3D scanner. The influence of injection moulding process parameters on the introduced novel quality parameters was investigated. The developed moulding runout quality parameter proved to be effective in evaluating the shrinkage that can occur in the injection moulding process. The novel moulding runout parameter returned an average value of −21.8 μm in comparison to 29.4 μm exhibited by the standard parameter on all the gears, where the negative value points directly to mould shrinkages. The rate of cooling was determined to be the most influential factor for the shrinkage of the gear. The developed areal parameters demonstrated to be advantageous in characterising the deviations on the teeth more comprehensively.

Effect of interfacial nanostructures on shear strength of Al-PPS joints fabricated via injection moulding method combined with anodising

The high-strength direct joining of metal to polymer has attracted increasing attention in the weight reduction of equipment. In this work, porous anodic alumina (PAA) films with different interpore distances and pore diameters were fabricated on the commercial 6063T5 Al alloy via anodising, followed by etching. Then, the glass fibre/mineral filling polyphenylene sulphide (PPS) was directly joined with Al by using injection moulding method. The relationships between the interfacial structure and bonding strength of Al-PPS joints were systematically investigated and discussed. Results showed that the shear strength of the joints was significantly affected by the porosity, wettability, and hardness of the PAA films. With the increase in etching duration, the porosities of the PAA films increased, whilst their contact angles decreased (from 110° to 20°). However, excessive porosity (>45%) could lead to the weakening of PAA films. In general, the shear strength of joints increased first and then decreased with the etching duration. The maximal joint strength of the Al-PPS joints was ~21.2 MPa, which reached ~82% of the theoretical limit (~25.5 MPa). The images observed by scanning electron microscope and atomic force microscope indicated that the depth of PPS injected into the nanopore could reach >500 nm. The fracture surfaces of the Al-PPS joint with the highest strength could be divided into three different zones in accordance with their morphologies and failure mechanism. In general, these results are of great importance to the further design and optimisation of metal-polymer joints fabricated using the presented method.

Analysis of the Manufacturing Process Using Polyproplene by Plastic Injection Molding Method

Polypropylene is the most widely used type of polymer material. It is widely used in many areas from food to textile. Plastic injection molding is one of the most common methods used in the production of plastic parts. Many products in different sizes and shapes can be produced with plastic injection molding. In our study, carved furniture was produced from polypropylene raw material by plastic injection method and the parameters suitable for production were specified. Factors such as pressure, temperature, time, and speed are factors that directly affect the production and end product quality. For this reason, it is very important that the parameters are optimized well. The total cycle time of the production is determined as 40 seconds, and the final product is a product with 170 grams and 0.9 mm wall thickness. At the end of the study, the cost expenses of the sample firm were specified.

On the question of porosity of aluminum castings obtained by injection molding

The constantly accelerating pace of life and the rapid growth of industry inevitably lead to an increase and toughening of requirements for manufactured products. Therefore, the scope of application of special methods for obtaining blanks is expanding, among which one of the leading places is occupied by the injection molding method (IMM). The advantages of the IMM include, first of all, high productivity and dimensional accuracy of castings, the minimum need for mechanical processing, the possibility of obtaining castings with a complex external configuration, as well as the automation of the process. The main disadvantages are the high cost of molds, as well as the insufficient quality of the resulting castings, primarily the gas subsurface porosity and gas roughness. In most cases, the IMM is used to obtain castings from zinc, copper and aluminum alloys. The most widespread are aluminum alloys, which make it possible to manufacture castings with different properties depending on the alloy grade. For most grades of aluminum alloys, disadvantages associated with sufficiently high melting temperatures and chemical activity when interacting with the mold are inherent. All these factors make the IMM a complex technological process, for which the challenge of insufficient quality of the resulting castings is urgent. Traditionally, this issue is solved by choosing the technological modes of the casting process. However, in some cases, it is very difficult to achieve high quality castings only by selecting technological modes. The authors have proposed an universal method for improving the quality of castings by applying the developed protective coatings on forming surfaces of molds by cathode-ion bombardment (CIB). The paper presents the results of experimental studies proving the effectiveness of the use of wear-resistant coatings obtained by the CIB method of various compositions in comparison with the traditionally used nitriding in terms of gas and surface porosity, as well as the roughness of castings. The economic substantiation of the efficiency of the use of CIB coatings in comparison with nitriding is presented.

Investigation the Effect of Additive Content and Sintering Temperature on the Mechanical Properties of Clay-Bonded and Glass-Bonded Ceramic Parts Produced by Low Injection Molding Method

Investigation the Effect of Additive Content and Sintering Temperature on the Mechanical Properties of Clay-Bonded and Glass-Bonded Ceramic Parts Produced by Low Injection Molding Method