Autodesk Moldflow Research Articles

High Temperature Adiabatic Heating in µ-IM Mould Cavities-A Case for Venting Design Solutions.

Micro-injection moulding (µ-IM) is a fabrication method that is used to produce miniature parts on a mass production scale. This work investigates how the process parameter settings result in adiabatic heating from gas trapped and rapidly compressed within the mould cavity. The heating of the resident air can result in the diesel effect within the cavity and this can degrade the polymer part in production and lead to damage of the mould. The study uses Autodesk Moldflow to simulate the process and identify accurate boundary conditions to be used in a gas law model to generate an informed prediction of temperatures within the moulding cavity. The results are then compared to physical experiments using the same processing parameters. Findings from the study show that without venting extreme temperature conditions can be present during the filling stage of the process and that venting solutions should be considered when using µ-IM.

The influence of fiber orientation and geometry-induced strain concentration on the fatigue life of short carbon fibers reinforced polyamide-6

Static and fatigue mechanical properties of a polyamide-6 reinforced with a 20% weight fraction of short carbon fibers (PA6-20CF) material were investigated by means of static and fatigue tensile tests on both unnotched and notched specimens. SEM pictures were also taken on the fracture surface of specimens tested under static, low cycle failure (LCF) and high cycle failure (HCF) conditions, allowing to correlate the cycles to failure with the deformation pattern of the polymer matrix. Accordingly, two strain-approach-based fatigue models were developed and allowed accounting for the different influence of stress, and strain, concentration on the fracture behavior for static failure, LCF and HCF. To account for the variation of mechanical properties with fiber orientation, Autodesk Moldflow Insight simulations were performed, and the resulting fiber orientations were mapped into Abaqus via the mapping program Autodesk Helius. The model was validated by utilizing it for the prediction of the fatigue life of a complex shape part, showing a maximum error equal to 13.7%, in comparison to experimental results.

Numerical simulation and experimental investigation of mold filling and segregation in low-pressure powder injection molding of metallic feedstock

The mold filling stage of the low-pressure powder injection molding process and the segregation of the injected part were numerically simulated and validated by an experimental approach. The numerical simulations were performed using the Autodesk Moldflow Synergy 2019 package to specifically investigate the injected length, the front velocity, the filling time, the pressure, and the shear rate, as well as to assess the magnitude of powder segregation after an injection. Furthermore, thermal and rheological characteristics of feedstock were experimentally measured to establish the constitutive equations to be provided to Moldflow. Numerical simulation results were validated with real-scale injections (with feedstock temperatures varying between 80 and 100 °C), using a laboratory injection press. Experimental characterization and injection were conducted using a feedstock formulation based on 17–4 PH stainless steel powder (60 vol% of powder) combined with a low-viscosity binder system. The injected length, the melt front velocity, and the filling times predicted by the numerical model were in good agreement with the experimental observations, with relative differences varying from 3.1 to 4.4%. Since the injections were performed and simulated at constant volumetric flow in a constant cross-section mold cavity, the mold filling results confirm that the feedstock temperature has no influence on the injected lengths, but rather, on the injection pressure. Moldflow also captured the absence of segregation occurring during injection, with experimental measurements of the local solid loading confirming the ability of the numerical model to successfully predict the homogeneous distribution of the powder (i.e., no segregation) within a simple shape mold cavity. Although theses interesting simulation capabilities of the injection and segregation behaviors were obtained for simple-shape components, the present work represents, to the best of the authors’ knowledge, the first simulation of low-pressure injection molding of metallic feedstock.

ТОПОЛОГИЧЕСКАЯ ОПТИМИЗАЦИЯ КОНСТРУКЦИЙ ИЗ КОРОТКОАРМИРОВАННЫХ КОМПОЗИТОВ С УЧЕТОМ АНИЗОТРОПИИ МАТЕРИАЛА, ОПРЕДЕЛЯЕМОЙ РАСЧЕТОМ ИХ ЛИТЬЯ ПОД ДАВЛЕНИЕМ

A methodology is presented for solving the related problem of topological optimization of short-reinforced composites structures, considering the attributes of the material anisotropy by fully solving the injection molding problem. The methodology is considered on the example of optimizing a bracket loaded with a shearing force. The solution is performed in the Ansys Topology Optimization module using the Sequential Convex Programming method. The anisotropic formulation of the problem involves the calculation of the injection molding process in the Autodesk Moldflow system on a mesh reduced by intermediate iterations of topological optimization, and updating the material properties at intermediate steps of the algorithm based on a C program. It is shown that the anisotropy of the material can lead to the displacement of weld lines beyond the main load-bearing structural elements and to increase the stiffness of short-reinforced composite materials structures.

Injection Moulding Recommended Parameters Simulation Analysis of Rice Husk Composite

Study of recommendation parameters for injection moulding process was carried out with aid of Autodesk Moldflow Insight. Rice husk filled low-density polyethylene was used as the raw material. Standard dog- bone shape mould with ASTM were used throughout the simulation analysis. The investigations were carried out on fill analysis, fill + pack analysis and cool analysis on injection moulded dog-bone shape. From the simulation analysis, the recommended parameters of the injection moulding process for rice husk composites were determined.

Design and Analysis of the Sleeve Ejection System in Injection Molding Die for Trolley Wheel

Plastic is a commonly used engineering material. Properties like availability, less weight, moldability and corrosion resistance are a few among many desirable properties, due to which most of our usable products are made of plastic. This vital use encourages manufacturing industries to make plastic products in large scale. The industries are able to meet this demand and supply requirement, using various methods of processing plastics. All the methods and tools for processing plastics contribute to mass production. Injection molding dies are one among the many tools used for processing plastics to the required shape. Usually it is very easy to learn and perform the injection molding method to obtain plastic products. But to achieve quality components in mass production, one needs proper implementation of each die-set element in an injection molding die. Ejection of component from the die cavity is one phase in injection molding process and it has similar importance like all other phases. This paper aims at implementation of sleeve ejection system for plastic trolley wheels. Software used for modeling of parts is UG Nx 9.0 and that for the simulation of process parameters is Autodesk Moldflow Adviser 2015. Stress and deformation analysis is done by ANSYS 16.0 version.

Injection Molding Cycle Time Reduction for Automobile Headlamp Shell in Moldflow

In the injection molding cycle, the cooling time consumes more than 70% of the molding process, optimizing the molding cycle time can be done through the selection and the design of appropriate cooling system that will be able to achieve equal distribution of the temperature along the part and quickly dissipate the heat. This paper presents an analytic study on the simulation of cool + fill + pack + warp in Autodesk Moldflow 2012 for the automobile headlamp shell, the simulation is made on of four different cooling systems, after comparison of the obtained results, the Spiral Zigzag Conformal Cooling Channel (SZCC) has the lowest time required for the part to reach the ejection temperature, with 61.22 seconds, it also shows an improvement on the volumetric shrinkage with the part’s deflexion that have been reduced from 2.15 mm on the first design to 2.12 mm, making Spiral Zigzag Conformal cooling the best solution for this model.

Injection mold design of reverse engineering using injection molding analysis and machine learning

Plastic composites are used in vehicle components to improve fuel efficiency. Thus, the warpage of injection-molded plastic parts has become a quality issue. Factors, such as product shape and thickness, resin, and other injection molding conditions, can be modified to improve the warpage problem. However, if these factors are set with no possible adjustments, reverse engineering may be required. Reverse engineering is a difficult process that requires many trials and errors; thus, it is only used as a last resort. With respect to the warpage issue, reverse engineering considers the following: (1) Predicting and (2) modeling the warpage in opposite directions. Autodesk Moldflow Insight accommodates these key considerations, but many researchers are reluctant to use it. Although existing injectionmolding analysis programs are mainly used to predict qualitative results, computer-aided engineering (CAE) for reverse engineering requires quantitative analysis. Hence, the considerations are different from the existing analyses. An error in warpage prediction may lead to a costly mold modification because of the molds' complex structures. Quantitative warpage prediction for reverse engineering depends on process variables; thus, understanding how warpages are affected by uncertain process variables is important to improve the reliability of reverse engineering. Moreover, even if appropriate process variables are set, they cannot be applied due to tolerance in lengths. For this reason, mold shrinkage must be identified before designing a mold. This study conducted injection molding analysis for a radiator tank that uses glass fiber-reinforced plastic using Autodesk Moldflow Insight 2018.2. Data for warpage prediction were generated in accordance with five process variables to identify the relationship between the level of warpage and process variables. CAE also showed the level of mold shrinkage that can reduce warpage. In addition, a predictive model was created using the multilayer perceptron (MLP)- supervised learning technique, which is a deep learning method for artificial neural networks. The predictive model was compared with typical regression models, such as polynomial regression (also known as response surface model), EDT and RBF, to determine the optimal approximation model. The real modeling time for a radiator tank product is 1 h, but the MLP approximation model required only 1 min and 8 s to perform 8530 iterations with a similar reliability.

Influence of Gates on Quality Parameters for a Joystick Handler

The paper presents an analysis of a molding process and the structure of the mold for a joystick handler. At the simulation of the molding process are analyzed multiple variants changing the number and position of the gates, the runner system, and the number of the pockets. Several combinations of technological parameters are taking into account in establishing the set of variables, which gives the best quality for the part. With the aid of Autodesk Inventor and Moldflow software, a complete set of quality parameters are predicted.

Injection molding of short coir fiber polypropylene biocomposites: Prediction of the mold filling phase

The mold‐filling phase in injection molding is the most important one because the material flow behavior controls the final part structure. In this work, the effect of melt rheology on the flow front progression of coir fiber (2.5, 5, 10, and 15 wt%) filled polypropylene is investigated. The flow behavior is predicted using the incompressible Navier–Stokes equations to determine the flow front shape and position and the model proposed is in good agreement with the experimental results for the range of conditions studied. Finally, to provide a better understanding of the effect of different processing conditions (pressure, melt, and mold temperature) on the flow front evolution, several simulations were performed using Autodesk Moldflow Insight. POLYM. COMPOS., 40:4042–4055, 2019. © 2019 Society of Plastics Engineers

Optimization of process parameters in plastic injection molding for minimizing the volumetric shrinkage and warpage using radial basis function (RBF) coupled with the k-fold cross validation technique

Abstract In this study, a multi-objective design optimization method based on a radial basis function (RBF) model was applied to minimize the volumetric shrinkage and warpage of hip liners as an injection-molded biomedical part. The hip liners included an ultrahigh molecular weight polyethylene (UHMWPE) liner and UHMWPE reinforced with a nano-hydroxyapatite (nHA) liner. The shrinkage and warpage values of the hip liners were generated by simulation of the injection molding process using Autodesk Moldflow. The RBF model was used to build an approximate function relationship between the objectives and the process parameters. The process parameters, including mold temperature, melt temperature, injection time, packing time, packing pressure, coolant temperature, and type of liner, were surveyed to find the interaction effects of them on the shrinkage and warpage of the liners. The results indicated that the addition of nHA helps the liners to obtain more dimensional stability. The model was validated by the k-fold cross validation technique. Finally, the model revealed the optimal process conditions to achieve the minimized shrinkage and warpage simultaneously for various weights.

Outstanding problems of numerical simulation of the process of injection molding of PIM-feedstocks and component quality

Based on the experience of foreign colleagues studied in publications and own exploratory work, the authors offer their own vision of the current knowledge and problems of numerical simulation of the injection molding process of feedstoks in PIM-technology. The results of the simulation of the injection molding of challenging component are presented in the Autodesk Moldflow software package.

Optimization of fiber prediction model coefficients in injection molding simulation based on micro computed tomography

Fiber‐reinforced thermoplastic for low weight application become increasingly important for many industrial branches. During the injection molding of short fiber‐reinforced thermoplastic parts the fibers become orientated. This orientation is determined on the one hand by the geometry of the part, and on the other hand by the injection molding parameters, and influence the mechanical behavior of the part. The determination of the fiber properties that is, the orientation distribution of the fibers, is therefore of considerable interest. Since a more accurate fiber orientation prediction of the injection molding simulation will lead to a more precise structural simulation the objective of the present work is to achieve a preferably accurate orientation distribution. To describe the orientation distribution of the fibers, the fiber orientation tensor defined by Advani and Tucker (Advani and Tucker, Journal of Rheology, 31, 751 (1987)) was used. To determine the entries of this tensor micro computed tomography scans (μCT‐scans) of an injection‐molded plate, as well as an injection‐molded specimen with different cross section and shape were performed. Injection molding simulation using Autodesk Moldflow Insight were carried out. The residual strain closure (RSC) model was the underlying model to depict the fiber orientation distribution, or rather the orientation tensors. The two model parameters, the fiber interaction coefficient Ci and the scalar factor κ, were adapted by an optimization procedure, in such a way that the orientation distributions of the simulations fit the results of the μCT‐analysis at its best. POLYM. ENG. SCI., 59:E152–E160, 2019. © 2018 Society of Plastics Engineers

Desain dan Optimasi Injection Mold Sistem Slider pada Produk Stick T15

The design of injection molding is the initial process to produce a large-scale product of plastic material which heated and injected into the mold. Design of the preform mold using the plastic material polyethylene terephthalate with the construction of the slider, so that the products which was made have undercut and can’t be made in the core section and cavity. The purpose of this design is to design the slider on the product preform. The software which used for this design using CATIA V5R19 and simulation software production using Autodesk Moldflow Insight 2016. The step on designing a unit injection mold in the preform includes several steps. The first step is identify the product, the calculation of the cooling and input the data calculation result to an moldflow. The second step is design construction slider and determine the mold material as well as calculating the construction mold. The third step is pour the results of the design in figure 2D. Based on the analysis results from moldflow obtained cooling optimal.i.e. the type of cooling series type 2, and if can be concluded construction of the mold said to be safe if the stress, the style and the determination of material which occurs under the stress and style of permit.

Mechanical Properties Studies of Components Formulation for Mixing Process Contain of Polypropylene, Polyethylene, and Aluminium Powder

Certain powder and others components can induce toxic reactions if not properly handled in the mixing stage. During handling, the small particles can become airborne and be trapped in the lungs, another concern is inhomogeneities in the mixing process. Uniform quantities of the particles of the components are needed in all portions of the mixture. This paper reports the results of mechanical properties studies of mixing three components formulation for mixing process. Contain of Polyethylene (PE), Polyprophylene (PP) and Aluminium Powder. Powder mixer, Autodesk mold flow and computer based on excell method was carried out to study the influence of each formulation component on the flow %, PE 20% and Aluminium powder 2%. Macroscopic optic and macro photo was carried out to identify the homogenity of mixing, tensile test for identify the strength of component after mixing. Finally the optimal tensile test with composition PP 785,PE 20% and Aluminium powder 2% at speed 52 rpm, temperature 1500C, the tensile strength 20,92 N/mm2. At temperature 1600C, speed 100 rpm the optimum tensile strength 17,91 N/mm2. The result of simulation autodesk mold flow adviser the filling time 6 seconds. Otherwise on manual hot hidraulic press the time of filling 10 seconds.

3D Scanning Techniques Complements Predictive Engineering for Mold Flow Analysis

This study is an attempt to close the loop between simulation and reality. Many industries are of the opinion that a simulation does not really predict the actual process and is only a colorful plot for presentation. An accurate simulation can save cost by a multitude of ways like material savings, process optimization, cycle time reduction, improved quality of parts and so on. A validation of the simulation in a real time scenario will instil necessary confidence in the accuracy of the simulation study thereby closing the loop between simulation and reality In the present study, the mold flow analysis is conducted for the back plate of LED emergency light with the help of Autodesk moldflow simulation software to generate the gate location, feed system building, cooling channel wizard, fill time and to check warpage and then the result is verified by superimposing the scan data of the physical part which is scanned in Steinbichler Blue Light 3D Scanner and CAD model in Geomagic verify.

Application of RSM to Optimize Moulding Conditions for Minimizing Shrinkage in Thermoplastic Processing

This study focuses on the analysis of plastic injection moulding process simulation using Autodesk Moldflow Insight (AMI) software in order to minimize shrinkage by optimizing the process parameters. Two types of gates which is single and dual gates have been analysed. Nessei NEX 1000 injection moulding machine and P20 mould material details are incorporated in this study on top of Acrylonitrile Butadiene Styrene (ABS) as a moulded thermoplastic material. Coolant inlet temperature, melt temperature, packing pressure and cooling time are selected as a variable parameter. Design Expert software is obtained as a medium for analysis and optimisation to minimize the shrinkage. The polynomial models are obtained using Design of Experiment (DOE) integrated with RSM Center Composite Design (CCD) method in this study. The results show that packing pressure is a main factor that contributed to shrinkage followed by coolant inlet temperature, while melt temperature and cooling time has less significant for both single and dual gates. Meanwhile, single gate shows a better result of shrinkage compared to the dual gates.

Improving Warpage with Milled Groove Square Shape Conformal Cooling Channels

Warpage is a common issue in an injection moulding process due to non-uniform temperature variation causing differential shrinkage on the moulded parts. In designing moulds for injection molding process, it is very difficult to achieve efficient cooling with uniform thermal distribution. Most of researchers focus on an optimisation of processing parameters to improve the warpage. However, the conformal cooling channels have advantages with the uniform distance between center of cooling channels and mould surfaces in order to get a better thermal distribution thus reducing the warpage. This paper presents the Milled Grooved Square Shape (MGSS) conformal cooling channels which provide more uniform in cooling and have a bigger effective cooling surface area cross sectional area and comparing to circular and others type of cooling channels with similar cross section. A case study on front panel housing is investigated and the possibility of fabrication the conformal cooling channels on hard tooling for injection moulding process which is easier to design, fabricate and assemble compared to other method are presented. The performance designs of straight drilled are compared to the two types of MGSS conformal cooling channels by using Autodesk Moldflow Insight (AMI) 2012. The analyses show that the both types of MGSS conformal cooling channel suggested can provide a more uniform thermal distribution and able to reduce the warpage on the molded part compared to the straight drilled cooling channels.

MOULDABILITY OF WOOD FILLER REINFORCED POLYPROPYLENE COMPOSITE FOR INJECTION MOULDED ENGINE COVER USING MOULD FILING SIMULATION

Feasibility studies about processing lignocellulosic reinforced polymer composites by injection moulding have been receiving widespread attention nowadays. The aim of this research was to identify the optimal selection of parameters, significant parameters, and effects of the injection-moulding parameters during the post filling-stage. In this simulation study, the modelling of an automotive component, namely the Proton Waja CAMPRO car engine cover, required a 3-D model and mesh generation to obtain the mouldability of its composite material using the injection moulding process. Autodesk Moldflow Insight® was used to simulate and analyse the injection-moulding process. Therefore, 60 wt% of wood filler reinforced polypropylene was evaluated under optimised injection parameters (injection temperature, mould temperature, injection pressure and flow rate) during the post-filling stage simulation (filling time, average velocity, volumetric shrinkage, sink marks, and shear stress). In addition, numerical simulation by the Taguchi method consisting of S/N ratio and ANOVA were used in this research to determine which significant factors would affect all responses. Based on the numerical simulation results, the flow rate shows the most significant parameter for the reduction of filling time, volumetric shrinkage, sink marks, and shear stress while also enhancing the average velocity on the car engine cover.

Simulation Tools Used at the Injection Mould Design

The article deals with the basic steps of injection mould design. The goal of the research was the proposition of the mould form so to be achieved the minimum waste and the shortest time of both mould filling and product cooling. Studied mould component is intended to serve as a stopper in the automotive spotlight. The simulations were realized for three designed types of running system and for four versions of cooling system. Due to the design optimization, the pressures, originated inside the cooling system and inside the mould cavity during the injection moulding process, were also investigated. 3D model of the mould was created in Autodesk Inventor Professional software and then solidification of material was simulated in Autodesk Moldflow. On the basis of the best solution, real form was manufactured and placed into injection moulding machine Arburg Allrounder 320 C.