scholarly journals Process Optimization and Implementation of Online Monitoring Process in the Transfer Molding for Electronic Packaging

2019 ◽  
Vol 16 (4) ◽  
pp. 157-175
Author(s):  
Burcu Kaya ◽  
Jan-Martin Kaiser ◽  
Karl-Friedrich Becker ◽  
Tanja Braun ◽  
Klaus-Dieter Lang
Keyword(s):  
Process Parameters ◽  
Process Model ◽  
Online Monitoring ◽  
Molding Process ◽  
Monitoring Method ◽  
Influence Of Process Parameters ◽  
Transfer Molding ◽  
Molding Compounds ◽  
Material Characteristics ◽  
The Impact

Abstract The quality of molded packages heavily depends on the process parameters of the molding process and on the material characteristics of epoxy molding compounds (EMCs). When defects are introduced into the electronic packages in one of the last steps in the manufacturing process, namely, during encapsulation, it may cause high failure costs. To decrease the number of defects due to the molding process, a comprehensive understanding of the impact of process parameters and variations in the characteristics of the EMC on package quality is necessary. This study aimed at supporting a deeper understanding of the influence of process parameters and variations in the material characteristics of the EMC on package quality. A systematic approach was introduced to generate a process model describing the correlation between process parameters and package quality to obtain optimum process parameters for the transfer molding process. The influence of the alterations in material characteristics of the EMC due to prolonged storage duration and humidity on void formation and wire sweep was investigated. An online monitoring method, dielectric analysis (DEA), was implemented into the transfer molding process to monitor the variations in the cure behavior of the EMC. A second molding compound was used to analyze the similarities in the alteration behavior of the molding compounds when subjected to the same preconditioning and to generalize the characteristic information obtained from DEA.

Numerical Optimization of Shrinkage and Warpage on the Injection Molding Process Parameters of Electrical Connector

2017 ◽  
Vol 868 ◽  
pp. 183-191 ◽  
Author(s):  
Yun Wang ◽  
Li Yu Chen ◽  
Xia Ming Yang ◽  
Yan Zhao ◽  
Zhen Ying Xu ◽  
...  
Keyword(s):  
Injection Molding ◽  
Process Parameters ◽  
Mold Temperature ◽  
Influential Factors ◽  
Injection Molding Process ◽  
Molding Process ◽  
Melt Temperature ◽  
Influence Of Process Parameters ◽  
Filling Time ◽  
The Impact

Integrated with orthogonal design method and numerical simulation, injection molding process of the Y-type electrical connectors was conducted to study the influence of process parameters on volume shrinkage rate and maximum warpage, which are regarded as product quality indices. The multi-indices valuation model for the main influencing factors of the process is developed. The influencing sensitivity to the multi-objective of the processing parameters, such as melt temperature, mold temperature, injection time and holding pressure, is determined by range analysis. Through analyzing the diagrams of influential factors, the optimized process parameter diagram is obtained and verified by simulation. The optimum parameters minimizing the warpage defect and shrinkage are: melt temperature (528K), mold temperature (338K), filling time (0.6s), holding pressure (100%) and holding time (10s). The results show that it is effective to balance the impact of process parameters on the shrinkage and warpage. The work can provide optimal design and process reference for the quality control and assembly precision.

Manufacturing Modeling of Three-Dimensional Resin Injection Pultrusion Process Control Parameters for Polyester/Glass Rovings Composites

2006 ◽  
Vol 129 (1) ◽  
pp. 143-156 ◽  
Author(s):  
A. L. Jeswani ◽  
J. A. Roux
Keyword(s):  
Process Parameters ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Fiber Reinforcement ◽  
Resin Flow ◽  
Molding Process ◽  
Fiber Volume ◽  
Liquid Resin ◽  
Pultrusion Process ◽  
The Impact

Pultrusion, sometimes referred to as continuous resin transfer molding process, is a continuous, cost-effective method for manufacturing composite materials with constant cross sections (such as rod stock, beams, channels, and tubing). The objective of this study is to improve the fiber reinforcement wetout and thus the quality of the pultruded part in the injection pultrusion process. The complete wetout of the dry reinforcement by the liquid resin depends on various design and process parameters. The process parameters modeled in this study are fiber pull speed, fiber volume fraction, and viscosity of the resin. In the present work, a three-dimensional finite volume technique is employed to simulate the liquid resin flow through the fiber reinforcement in the injection pultrusion process. The numerical model simulates the flow of polyester resin through the glass rovings and predicts the impact of the process parameters on wetout, resin pressure field, and resin velocity field. The location of the liquid resin flow front has been predicted for an injection slot as well as for five discrete injection ports.

Analysis of the process influences on injection molded thermosets filled with hollow glass bubbles

2018 ◽  
Vol 38 (7) ◽  
pp. 695-701
Author(s):  
Christian Hopmann ◽  
Matthias Theunissen ◽  
Stefan Haase
Keyword(s):  
Mechanical Properties ◽  
Process Parameters ◽  
Processing Parameters ◽  
Injection Molding Process ◽  
Filler Materials ◽  
Molding Process ◽  
Molding Compound ◽  
Hollow Glass ◽  
Molding Compounds ◽  
Wide Range

Abstract Thermoset molding compounds have a wide range of beneficial properties such as easy handling, high temperature, chemical resistance, low shrinkage as well as low electrical conductivity. However, these properties come at the cost of a higher density than technical thermoplastic materials and thus the potential for lightweight applications is reduced. Due to the low viscosity of the resin within thermoset molding compounds a wide variety of filler materials can be used. The addition of low density hollow glass bubbles as a filler material in thermoset molding compounds offers the opportunity to decrease the density of the molding compound. At the same time the stiffness of the micro glass bubbles is expected to increase the stiffness of the material. In the present study, a thermoset molding compound was filled with different quantities of hollow glass bubbles and the effects of the filler content as well as the processing parameters were investigated regarding their effect on the weight and mechanical properties of the parts. Based on the results, significant weight reductions up to 5% were achieved. Furthermore, a significant impact of the process parameters on weight reductions was found. The results indicate that higher shearing reduces the weight. This can also contribute to damaging of the glass bubbles during the injection molding process. Similar results were found regarding the effect of process parameters on the mechanical properties.

On the effect of heat input in plasma microwelding of maraging steel

2017 ◽  
Vol 233 (3) ◽  
pp. 807-822
Author(s):  
Tinku Saikia ◽  
Mayuri Baruah ◽  
Swarup Bag
Keyword(s):  
Finite Element ◽  
Maraging Steel ◽  
Process Parameters ◽  
Weld Joint ◽  
Heat Input ◽  
Process Model ◽  
Welding Process ◽  
Fusion Welding ◽  
Welding Distortion ◽  
Influence Of Process Parameters

Maraging steel in known as ultra-high strength and toughness material widely used in aerospace industry and defense system. The joining of this material by fusion welding process experiences gigantic metallurgical transformation that have significant contribution toward the development of welding distortion, and transformation of austenite into martensite at very low temperature with significant increase in specific volume. In this study, a set of bead-on-plate welding is executed at microscale to establish feasible range of process parameters using plasma arc as a source of heat. Although, high-concentrated heat does not produce much distortion, the heat input to the weld joint experiences the difference in possible distortion. A finite element–based numerical process model is also developed to investigate the differential influence of process parameters on thermo-mechanical behavior of weld joint. An inverse approach is followed to estimate the unknown input parameters by integrating the finite element model with optimization algorithm. The integrated model predicts the shape and size of weld geometry and welding distortion that are well agreed with experimental values.

scholarly journals Optimizing Bladder Resin Transfer Molding Process to Manufacture Complex, Thin-Ply Thermoplastic Tubular Composite Structures: An Experimental Case Study

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4093
Author(s):  
Somen K. Bhudolia ◽  
Pavel Perrotey ◽  
Goram Gohel ◽  
Sunil C. Joshi ◽  
Pierre Gerard ◽  
...  
Keyword(s):  
Process Parameters ◽  
Composite Structures ◽  
Resin Transfer Molding ◽  
Low Permeability ◽  
Molding Process ◽  
Mechanical Fracture ◽  
Transfer Molding ◽  
Injection Process ◽  
Liquid Injection

The bladder molding process is primarily used in sporting applications but mostly with prepregs. Bladder-Assisted Resin Transfer Molding (B-RTM) presents the tremendous potential to automate and mass produce the complex hollow-composite profiles. Thin-ply, non-crimp fabrics (NCFs) provide excellent mechanical, fracture toughness, and vibration damping properties on top of the weight saving it offers to a final product. However, these fiber architectures are difficult to inject due to the resistance they provide for the polymer flow using the liquid injection process. Therefore, it is mandatory to optimize the process parameters to reduce the time for injection and simultaneously achieve better consolidation. This work presents a first, detailed, experimental case study to successfully inject a low-permeability, thin-ply, complex, thermoplastic tubular structure, and the effect of process parameters, boundary conditions, the associated manufacturing challenges, and proposed solutions are deliberated in this paper.

scholarly journals Material Characterization for Reliable Resin Transfer Molding Process Simulation

2020 ◽  
Vol 10 (5) ◽  
pp. 1814 ◽  
Author(s):  
Maria Pia Falaschetti ◽  
Francesco Rondina ◽  
Nicola Zavatta ◽  
Lisa Gragnani ◽  
Martina Gironi ◽  
...  
Keyword(s):  
Material Characterization ◽  
Resin Transfer Molding ◽  
Molding Process ◽  
Transfer Molding ◽  
Aerospace Applications ◽  
Need To Evaluate ◽  
Component Development ◽  
The Impact ◽  
Preliminary Phase

Resin transfer molding (RTM) technologies are widely used in automotive, marine, and aerospace applications. The need to evaluate the impact of design and production critical choices, also in terms of final costs, leads to the wider use of numerical simulation in the preliminary phase of component development. The main issue for accurate RTM analysis is the reliable characterization of the involved materials. The aim of this paper is to present a validated methodology for material characterization to be implemented and introduce data elaboration in the ESI PAM-RTM software. Experimental campaigns for reinforcement permeabilities and resin viscosity measurement are presented and discussed. Finally, the obtained data are implemented in the software and then compared to experimental results in order to validate the described methodology.

scholarly journals Influence of Compression Molding Process Parameters in Mechanical and Tribological Behavior of Hybrid Polymer Matrix Composites

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4195
Author(s):  
Thanikodi Sathish ◽  
Vinayagam Mohanavel ◽  
Thandavamoorthy Raja ◽  
Sinouvassane Djearamane ◽  
Palanivel Velmurugan ◽  
...  
Keyword(s):  
Polymer Matrix ◽  
Process Parameters ◽  
Polymer Matrix Composites ◽  
Natural Fibers ◽  
Compression Molding ◽  
Molding Pressure ◽  
Curing Time ◽  
Hybrid Polymer ◽  
Molding Process ◽  
The Impact

In recent days, natural fibers are extremely influential in numerous applications such as automobile body building, boat construction, civil structure, and packing goods. Intensification of the properties of natural fibers is achieved by blending different natural fibers with resin in a proper mixing ratio. This investigation aims to synthesize a hybrid polymer matrix composite with the use of natural fibers of flax and loops of hemp in the epoxy matrix. The synthesized composites were characterized in terms of tribological and mechanical properties. The Taguchi L16 orthogonal array is employed in the preparation of composite samples as well as analysis and optimization of the synthesis parameters. The optimization of compression molding process parameters has enhanced the results of this investigation. The parameters chosen are percentage of reinforcement (20%, 30%, 40%, and 50%), molding temperature (150 °C, 160 °C, 170 °C, and 180 °C), molding pressure (1 MPa, 2 MPa, 3 MPa, and 4 MPa), and curing time (20 min, 25 min, 30 min, and 35 min). From the analysis, it was observed that the percentage of reinforcement is contributing more to altering the fatigue strength, and the curing time is influenced in the impact and wear analysis.

VARTM Process Improvement for Repeatable and Improved Mechanical Properties of Composite Laminates

2009 ◽  
Author(s):  
Sanjay Sharma ◽  
Dennis A. Siginer
Keyword(s):  
Mechanical Properties ◽  
Process Parameters ◽  
Composite Laminates ◽  
Volume Fraction ◽  
Void Content ◽  
Molding Process ◽  
Fiber Volume ◽  
The Impact ◽  
Vartm Process

Quality of laminates produced by Seeman Composite Resin Infusion Molding Process (SCRIMP) is studied by comparing their Fiber Volume fraction and void content. SCRIMP is a variant of Vacuum Assisted Resin Transfer Molding (VARTM). Manufacturing process parameters are then identified and varied to study the impact on mechanical properties of laminated composites. Modification to SCRIMP is carried out by infusing the resin under additional pressure. Optimal process parameters for this modified SCRIMP process are suggested to yield laminates that are repeatable and consistent in quality. Void content is reduced in the composite laminates by altering the vacuum pressure level. Thickness gradient commonly found in SCRIMP processed laminates is eliminated by allowing longer de-bulking time. Final laminate quality is measured using ASTM standardized mechanical testing.

Experimental and Numerical Analysis of Liquid-Forming

2015 ◽  
Vol 651-653 ◽  
pp. 842-847 ◽  
Author(s):  
Johannes Zimmer ◽  
Daniel Klein ◽  
Markus Stommel
Keyword(s):  
Process Parameters ◽  
Temperature Drop ◽  
Liquid Product ◽  
Forming Process ◽  
Molding Process ◽  
Influence Of Process Parameters ◽  
Inertia Effects ◽  
Thermally Induced ◽  
Blow Molding ◽  
Stretch Blow Molding

The packaging of liquid products is conventionally realized by using two production stages, which are the stretch blow molding and the filling. In the stretch blow molding process, hot polyethylene terephthalate (PET) preforms are inflated by pressurized air into a cavity to form plastic bottles. In a follow-up process, these packages are filled by a separate machine with the desired liquid product. In contrast to that, liquid-forming combines the blowing and filling stages by directly using the liquid product to form a plastic bottle. Through this substitution, two main challenges arise. Firstly, there are significant inertia effects through the liquid mass, leading to additional reaction forces and a spatially inhomogeneous pressure distribution inside the preform. Secondly, the heat transfer between preform and fluid is drastically increased. Because of this cooling effect, a specific combination of forming speed as well as initial preform and liquid temperatures is necessary to avoid thermally induced preform rupture. This is based on the fact that the formability of PET rapidly declines below its glass transition temperature (Tg). Consequently, a process control requires the knowledge of how the process parameters influence the preform cooling. In this paper, a numerical simulation of the liquid-forming process (LF) is introduced including the preform cooling during forming. In addition, the strain-dependent self-heating effect of PET is implemented. Process experiments under different parameter combinations are conducted using simplified bottle geometry. Through a comparison of the results from experiments and from simulation, the influence of process parameters on the temperature drop and thus on thermally induced failure is determined. In this way, process understanding and control are increased.

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