Injection Moulding Research Articles

Synthesis of micro-micro titanium composite powder with the electrostatic adsorption process

Abstract This study investigates the production of commercially pure grade 4 titanium (Ti) composite powder via electrostatic adsorption. Unlike previous research focusing on nano-micro particles, this study explores the utilisation of surface charges (ions) to form a micro-scale composite powder, offering a novel approach in the field. The study investigates the impact of key electrostatic adsorption variables — pH value, stirring duration, host particle size and guest particle loading — on adsorption efficiency. It analyses the composite powder’s chemical composition, crystalline structures and adsorption efficiency using EDX, XRD and SEM techniques. The results show high adsorption efficiency is achieved when the guest (at 10% loading) and host particles are adjusted with pH-2 and pH-12, respectively, and stirred for 1 min. Moreover, more abundant adsorption sites led to better efficiency of larger host particles. No significant changes were observed in the chemical and crystalline structure (remained the same; α-Ti) of the composite powder except for the presence of Na and Cl. The study uncovers methods for creating micro-micro Ti composite powder, optimising adsorption efficiency. The powder has diverse applications, including metal injection moulding, binder jetting, selective laser melting and other powder-based processes. This study investigates the creation of micro-micro commercially pure grade 4 titanium composite powder.

Finite Element Simulation of Injection Mold Design Integrating Different Structures of Conformal Cooling Channels

Injection molding (IM) is a process in which completely melted plastic material is injected into the mold cavity under high pressure at a specific temperature, and the molded product is obtained after pressure holding, cooling, and demolding. During the mold cooling process, the conformal cooling channel system can improve the uniformity of mold temperature, reduce warping deformation, and significantly improve product accuracy. However, the cost consumption of conformal cooling channels for the cavity and core of injection molds is significant, which is a distinct disadvantage. This paper proposes an innovative conformal cooling channel. Compared with conventional cooling channels, the warpage of plastic parts has been reduced by 0.3401 mm. Moreover, the cooling time difference between C2 and C4 is relatively small, about 7.9 s. Among them, C4 takes the shortest time, C1 takes the longest, and C4 is 4.371 s shorter than C1. Compared with C1, the cooling efficiency of C4 has increased by 35.48%. In addition, from a commercial value perspective, many mold manufacturing companies’ real production applications are better suited for using conformal cooling channels alone on the injection mold core. This paper establishes injection molding models under different working conditions, simulates the cooling of dynamic mold temperature molds, and analyzes the effects of fluid media and various fluid rates on mold temperature changes. The results indicate that the cooling effect of cooling water is significantly better than that of cooling oil at the same fluid rate. When the fluid rate increases from 0.75 L/min to 6 L/min, the effect of cooling oil on the temperature change in the mold is significantly higher than that of cooling water. The influence of mold temperature on the cooling medium’s fluid rate tends to stabilize once the cooling medium’s flow rate reaches a specific value.

Three-Dimensional Multi-Morphology TPMS-Based Microchannel Design Method for Conformal Cooling in Injection Molding

Abstract Triply periodic minimal surface (TPMS) possesses diverse morphological characteristics, such as pore sizes, porosity, and structural types. Integrating TPMS-based microchannels into micro-cellular cooling structures is advantageous for designing and controlling fluid characteristics within mold cooling channels. However, it is still difficult to design multi-morphology TPMS-based cooling microchannels that conform to the external shapes of injection molds. This work proposes a 3D multi-morphology TPMS-based design method that transforms 3D constraints into a combination of 2D constraints. First, a beta growth algorithm based on closed-loop constraints is proposed to transition different morphologies smoothly on the plane. Subsequently, a transition optimization algorithm along the normal direction of the plane is introduced to smoothly transition multi-morphology TPMS-based microchannels in all directions. With this layered approach, multi-morphology microchannels can be obtained with first-order geometric continuity under complex shape constraints. Finally, several TPMS-based conformal cooling structures are designed for an automotive hood cover. The results of finite element simulations show that the cooling structures generated by the proposed method have a better cooling effect than the conformal channels. It can be concluded that multi-morphology TPMS-based structures perform better by contrast with conformal channels as the average temperature of the cooling surface decreases by 8.48 K, and the standard deviation of temperature distribution decreases by 24.65%.

High-strength of additive-manufactured PEEK and Ti6Al4V structure via warm isostatic pressing: applications in medical implants and injection moulds

ABSTRACT Polymer–metal hybrid structures offer synergistic benefits in mechanical property control and lightweight design, making them valuable across various industries. In this study, we designed and developed a warm isostatic pressing (WIP) to fabricate a hybrid structure using additive-manufactured polyetheretherketone (PEEK) and Ti-6Al-4V (Ti64) with an octet-truss lattice structure (OT). The effects of the WIP temperature on the mechanical properties of PEEK were examined by subjecting the parts to different temperatures during the WIP and performing tensile tests. Additionally, to confirm the mechanical properties of Ti64 with OT, we performed a compression test according to the unit cell size (1, 2, 3 mm) at a density of 30% before and after the WIP. Accordingly, we joined a PEEK with superior tensile strength and Ti64 with OT using a WIP under the condition (330°C and 90 bar). Furthermore, we confirmed the superior joint strength of approximately 71.6–74.8% in terms of the tensile and shear strengths of the PEEK-Ti64 hybrid structures compared to the warm isostatic pressed PEEK. Finally, we demonstrated the feasibility of applying PEEK-Ti64 hybrid structures to biomedical implants such as spinal cages and lightweight injection moulds highlighting the potential in advanced manufacturing.

New design of two‐dimensional LQ control for batch processes with iterative learning error compensation

AbstractThis paper proposes a two‐dimensional infinite horizon linear quadratic iterative learning control (2D‐IHLQILC) strategy based on error compensation. The strategy aims to address the shortcomings of one‐dimensional infinite horizon linear quadratic control (1D‐IHLQC), which is unable to utilize historical batch information. Firstly, a novel extended state space model is established to describe the batch process, which provides more degrees of freedom for the controller design and enables additional adjustment of the batch process input increment and output increment. Secondly, an error compensation strategy is introduced using historical batch information, which extends the novel extended state‐space model from one to two dimensions and can effectively deal with the time delay problem. Finally, a novel 2D‐IHLQILC controller is designed, which empowers the controller to learn iteratively from historical batch information to improve the control performance batch by batch and to achieve full tracking of the setpoint trajectory. The effectiveness of the 2D‐IHLQILC is tested on the holding pressure control in the injection moulding process as an example.

Influence of the Injection Process on Two-Phase Separation in Stainless-Steel Metal Powder Injection Molding

Influence of the Injection Process on Two-Phase Separation in Stainless-Steel Metal Powder Injection Molding

Optimising Aesthetic Automotive Component Manufacturing: Comparative Analysis of Injection Pressure in Injection Compression Moulding (ICM) vs. Injection Moulding (IM)

Optimising Aesthetic Automotive Component Manufacturing: Comparative Analysis of Injection Pressure in Injection Compression Moulding (ICM) vs. Injection Moulding (IM)

Design of Combined Ahp-Topsis Model for Optimizing Selection of Injection Molding Machines

Design of Combined Ahp-Topsis Model for Optimizing Selection of Injection Molding Machines

Effects of 3D Printing Parameters on the Flexural Properties of Semi-Crystalline PEKK

Fused filament fabrication (FFF), a leading additive manufacturing (AM) methodology has revolutionised the production of 3D objects. FFF enables the manufacture of complex geometries not achievable with traditional manufacturing methods. This study investigates the use of the high-performance polymer, polyetherketoneketone (PEKK) for advanced AM applications in the growing field of in-space manufacturing (ISM), where lightweight recyclable metal alternatives can greatly reduce launch payloads. Utilising a response surface methodology, this research examines the effects of print speed, layer thickness, nozzle temperature, and build platform temperature on PEKK's mechanical, physical, and thermal properties.Optimum print conditions for maximising the flexural modulus were identified as 30mm/s print speed, 0.1mm layer thickness, 380°C nozzle temperature, and 140°C build platform temperature. These parameters improve the material's crystallinity by extending its residence time in the printer's heated chamber. This prolonged exposure facilitates better molecular alignment and reduces thermal gradients, leading to a 30% enhancement in crystallinity compared to conditions with higher print speeds and greater layer thicknesses. Scanning Electron Microscopy (SEM) and micro-computed tomography(µCT) analyses revealed that layer thickness significantly influences void formation, with thinner layers yielding superior interlayer bonding and reduced void volume. Differential Scanning Calorimetry (DSC) confirmed that increased crystallisation had a direct impact on flexural modulus, increasing it to 3682MPa, approaching 80% of PEKKs injection moulding performance. This study highlights the complex relationships between the FFF parameters and PEKK's mechanical properties, highlighting its potential for industrial and ISM applications.

Evaluation of the Recycling Conditions Through Injection Molding Using Fuzzy Logic Approach

Recycling plastic products is still essential and crucial in every country around the globe due to its positive benefits on the environment and the economy. There are several mixing procedures for recycling, and it is crucial to understand how these mixtures affect the quality of products by standards and specifications. Consequently, it is helpful to apply analysis and prediction techniques to find out scientifically. Artificial intelligence "AI" techniques are widely used in many manufacturing engineering fields such as recycling operations. This is because of the many advantages that artificial intelligence techniques offer, including the ability to reduce human errors, save time, provide digital support, and make objective decisions. This study intends to employ the fuzzy logic method as one of the "AI" techniques for predicting a significant property that customers frequently need based on their quality levels and standards. This study employed the injection molding process to forecast the values of a mechanical characteristic, specifically tensile strength, under specific operating conditions based on data from the authors' earlier work. This investigation was conducted using two distinct mixing plans. The first mixed all the raw materials, while the second mixed 50% of the raw materials with 50% of the recycled materials. The fuzzy logic results were acquired, and the mean absolute percentage error for the two plans was calculated. Additionally, the outcomes of the current study, which employed the fuzzy logic approach, were contrasted with those of the earlier study, which utilized the response surface methodology approach. Furthermore, the results showed that the response surface technique approach is more accurate than the fuzzy logic since it has the lowest mean absolute percentage error.

Effect of Sintering Temperature on Tensile Properties of Ti-6Al-4V Alloy Manufactured Through Metal Injection Molding

Titanium and titanium alloys exhibit low density, high strength and excellent corrosion resistance, and have become workhorses in modern aerospace and chemical processing industries. Recently, Ti-6Al-4V alloy has been manufactured through metal injection molding (MIM). MIM is widely utilized in various manufacturing industries due to the near-net-forming process, especially in the preparation of difficult-to-deform high-temperature alloys. Sintering temperature is vital to ensuring good tensile mechanical properties. In this work, Ti-6Al-4V alloy was sintered under various sintering temperatures, from 1150 to 1250 °C. The effect of sintering temperature on the mechanical properties was evaluated. The tensile test results exhibited that a yield strength of 896.35 MPa, an ultimate tensile strength of 980.83 MPa and plastic elongation of 9.61% were produced at 1150 °C for 4 h; a yield strength of 877.23 MPa, an ultimate tensile strength of 981.92 MPa and plastic elongation of 7.74% were produced at 1200 °C for 4 h; and a yield strength of 923.33 MPa, an ultimate tensile strength of 1002.24 MPa and plastic elongation of 6.57% were produced at 1250 °C for 4 h.

Effects of discrete fibre reinforcements on the wear resistance behaviour of polyamide-based spur gears

Abstract In many situations, the polymer gears are the perfect replacement for traditional metal gears. Compared to metal gears, the polymer gears will generate more heat at the gear tooth contact surface and more wear loss. Hence, this study aims to decrease the wear loss and increase the load-carrying capacity of the polymer gears. To achieve this, the reinforcement materials were added to the base polymer gear material. In this study, Nylon-66 was chosen as the polymer matrix material and an isolated glass fibre and steel grid were used as the reinforcement materials. Three different types of polymer spur gears such as Polyamide Gear (Nylon-66), Reinforced Polyamide Gear (Nylon-66+Glass Fibre), and Hybrid Glass Fiber Steel Grid Gear (Nylon-66+Glass Fibre+Steel Grid) named PG, RPG and HGFSGG were fabricated using injection moulding machine and each type of gears were compared for wear loss and specific wear rate under the similar testing conditions. The wear test was performed in the Forschungsstelle fur Zahnrader und Getriebebau (FZG) test rig at 1500 rpm with an applied load of 20 N for 12.5 hours continuously. From the test results, it was identified that HGFSGG polymer spur gears have exhibited a lower surface temperature and better wear properties compared to the other two types of spur gears. From the Scanning Electron Microscope (SEM) analysis, it was noticed that the PG spur gear exhibited deep and uniform wear at the gear tooth surface. In contrast, RPG spur gear exhibited glass fibre distortion and abrasive-type wear. The SEM micrograph of HGFSGG spur gear reveals the presence of very few surface flaws in the gear tooth surface.

Development of a Low-Cost Automated Injection Molding Device for Sustainable Plastic Recycling and Circular Economy Applications

In response to the critical demand for innovative solutions to tackle plastic pollution, this research presents a low-cost, fully automated plastic injection molding system designed to convert waste into sustainable products. Constructed entirely from repurposed materials, the apparatus focuses on processing high-density polyethylene (HDPE) efficiently without hydraulic components, thereby enhancing eco-friendliness and accessibility. Performance evaluations identified an optimal molding temperature of 200 °C, yielding consistent products with a minimal weight deviation of 4.17%. The key operational parameters included a motor speed of 525 RPM, a gear ratio of 1:30, and an inverter frequency of 105 Hz. Further tests showed that processing temperatures of 210 °C and 220 °C, with injection times of 15 to 35 s, yielded optimal surface finish and complete filling. The surface finish, assessed through image intensity variation, had a low coefficient of variation (≤ 5%), while computer vision evaluation confirmed the full filling of all specimens in this range. A laser-based overflow detection system has minimized material waste, proving effective in small-scale, community recycling. This study underscores the potential of low-cost automated systems to advance the practices of circular economies and enhance localized plastic waste management. Future research will focus on automation, temperature precision, material adaptability, and emissions management.

Assessment of evolutionary multi-objective optimisation algorithms for thermoplastic injection moulding in aluminium moulds

In order for a plastic part manufactured by the injection moulding process to be of the desired quality, it is necessary to maintain control of the process parameters. To increase productivity and reduce defects in parts, various studies have been carried out to propose and evaluate methods for determining injection parameters, which are based on the use of experimental planning techniques as well as the application of optimisation algorithms. This work proposes an experimental design with 6 injection parameters (mould temperature, melt temperature, injection time, percentage of volume filled, packing time and packing pressure) to determine the initial search space for the NSGA-II and MOEA/D optimisation algorithms in relation to the use of aluminium moulds. This procedure was used via a computer code described in the PYTHON programming language to determine the appropriate injection parameters for minimising part warpage and injection pressure. The results showed that an increase in compaction pressure is associated with a reduction in warpage and vice versa. It was observed that the NSGA-II algorithm showed a greater diversity of points on the approximate Pareto frontier compared to the MOEA/D algorithm. In the case of the proposed study, MOEA/D presented a more viable solution, determining a lower packing pressure, less warping of the part and a shorter cycle time. The NSGA-II algorithm required around 4 hours more computational time than MOEA/D.

IMPLEMENTATION ANALYSIS OF OCCUPATIONAL SAFETY AND HEALTH IN THE OPERATING PROCESS A CRUSHER MACHINE AT THE PLASTIC WORKSHOP OF POLYTECHNIC ATK YOGYAKARTA

The Plastic Laboratory is one of the Laboratories of the Rubber and Plastic Processing Technology Study Program located at the Polytechnic ATK Yogyakarta. Plastic Workshop has several machines including Injection Molding machine, Blow Molding machine, Crusher machine and Mixer machine. In the operation of the crusher machine, there is a danger of microplastics produced as a by-product of the plastic enumeration process where the raw material is in the form of a practicum reject product on the Injection Molding and Blow Molding machines. Microplastics are types of plastic waste that are smaller than 5 mm in size and are grouped into 2 types, namely primary and secondary microplastics. The transfer of microplastics from the environment into the human body can occur both primary (directly from the environment into the human body in inorganic form) and secondaryly (entering through the food chain, by consuming organisms polluted with microplastics). Primary transfer can occur through the digestive (digesti) and respiratory (inhalation) systems. Microplastics can enter the human body primarily through inhalation, because microplastics can float in the air. From the hierarchy of hazard control, Administrative Control and the application of Personal Protective Equipment is the hierarchy that best suits the conditions and needs in the plastic laboratory. Where with Administrative Control, which ensures that all people in the laboratory and practice who operate crusher machines are required to use Personal Protective Equipment, the impact of microplastic hazards can be minimized properly. Another thing to note is that the provision of engineering gloves, respirator masks and earmuffs should be done periodically and in sufficient quantities.

Optimisation of process parameters in Arburg Plastic Freeforming for enhanced part density and geometric accuracy

Technological advances have increased the use of plastic-based additive manufacturing for production in a variety of industries that require high mechanical properties while maintaining geometric precision. The Arburg Plastic Freeformer (APF) process, unlike other filament-based technologies, uses standard plastic granules used in mass production in injection moulding machines. This study focuses on optimising the interaction of three critical process parameters: layer thickness (LT), droplet aspect ratio (DAR) and discharge rate (DR). Previous studies have mainly varied individual parameters to evaluate mechanical and geometrical properties. In contrast, this work analyses these parameters as a whole and evaluates their combined effects on residual porosity and geometric accuracy. APF relies heavily on supports to sustain the printed part, with a smaller achievable self-supporting overhang angle compared to the Fused Filament Fabrication (FFF) printing process. For this reason, this study investigates two compatible materials, ABS Terluran GP35 and a water-soluble PVP compound named Armat11. Cylindrical and cubic samples were 3D printed using different combinations of LT, DAR and DR. A total of 150 cubic samples were printed to assess the geometric dimensional accuracy and repeatability of printing in the plate position using permutations in the printing plate. Subsequently, 30 cylindrical samples were printed for micro-CT analysis, reconstructed by CT file segmentation and compared with the ideal CAD model, in addition to the characterisation of residual porosity. The results show that optimal combinations of LT, DAR and DR produce high density parts with repeatable geometric properties. In addition, a quantitative analytical model was developed to optimise arbitrary parameter sets. This comprehensive investigation provides important insights into the APF process and increases its potential for wider industrial applications.

Preparation of Flexible Polymer Sensor Material by Spatial Confining Forced Network Assembly Micro Injection Molding

Preparation of Flexible Polymer Sensor Material by Spatial Confining Forced Network Assembly Micro Injection Molding

Restoring with flowables: An injection moulding technique – A report of two cases

This case report showcases the conservative management of aesthetic anterior restorations for patients seeking to enhance their smiles using the highly filled flowable composite resin injectable moulding technique. This efficient method resulted in optimal, aesthetically pleasing outcomes, leading to high patient and dentist satisfaction. Direct veneers made from injectable flowable resin composites provide a minimally invasive treatment option, given that the case selection criteria are appropriately followed. Furthermore, this approach can be viewed as a more cost-effective alternative. However, additional follow-ups are essential to thoroughly assess the clinical longevity of both the restorations and the materials utilised.

Enhancing Dimensional Stability and Environmental Durability in Delrin-Molded Parts Through Advanced Annealing Techniques

This paper presents the implementation and optimization of an advanced annealing process designed to enhance the dimensional stability, moisture resistance, and crystallinity of Delrin-molded parts for demanding outdoor applications. Delrin, a widely used acetal resin, poses unique challenges in plastic injection molding due to its natural tendency to shrink post-molding and absorb moisture, which can compromise part performance in variable environmental conditions. By introducing a high-capacity annealing oven with precise temperature and humidity control, we achieved substantial improvements in part stability and durability. This process was developed through close collaboration with customer engineering teams and our in-house experts, ensuring the final product meets strict tolerance and environmental durability requirements. Results indicate that the annealing process effectively reduces dimensional variation, decreases moisture content by 75%, and increases crystallinity by 20%, making the parts robust enough to withstand extremes of heat, cold, and humidity. This study underscores the value of high-tech annealing solutions in the plastic injection molding industry, offering a blueprint for similar applications in advanced manufacturing. Keywords: Delrin Annealing, Crystallinity Enhancement, Dimensional Stability, Moisture Resistance, Environmental Durability, Plastic Injection Molding, Advanced Manufacturing Techniques, High-Capacity Annealing Oven, Quality Engineering, Process Optimization

A New Use Strategy of Artificial Intelligence Algorithms for Energy Optimization in Plastic Injection Molding

Plastic injection molding is a widespread industrial process in manufacturing. This article investigates the energy consumption in the injection molding process of fruit containers, proposing a new use strategy for the application of artificial intelligence algorithms. The aim is to optimize the process parameters, such as the mold temperatures, the injector temperatures, and the cycle time, to minimize energy consumption. This new use strategy, a hybrid use strategy, combines an unsupervised autoencoder with the K-Means algorithm to analyze production data and identify factors influencing energy consumption. The results show the capability of discovering different operating modes at different levels of energy requirements. An analysis of the process parameters reveals that the number of parts left to complete production, the current cycle counter, the number of shots left to complete the production, the material needed to complete the production, and the total time dedicated to production, so far, are the most relevant features for the optimization of the energy consumption per single piece. The study demonstrates the potential of common artificial intelligence algorithms if appropriately used to improve the sustainability of the plastic injection molding process.