Review
Polymer Science
Baishun Zhao, Yuanbao Qiang, Wangqing Wu, Bingyan Jiang
Summary: With the advancement of technology, ultrasonic-assisted micro-injection molding has become one of the core technologies for producing micro-parts, offering advantages such as high replication fidelity and cost-effectiveness. This review presents the latest research activities on the action mechanism of power ultrasound in various polymer micro-molding processes.
Article
Polymer Science
Vito Speranza, Sara Liparoti, Roberto Pantani, Giuseppe Titomanlio
Summary: Understanding the mechanisms that determine mechanical performances during micro-injection molding is crucial for meeting the demand for advanced plastic products. The ability to correctly predict morphology opens the possibility to forecast final part properties. The morphology of semi-crystalline polymers parts mainly consists of spherulites and fibrils, with the thermomechanical history experienced by polymer chains playing a key role.
Article
Polymer Science
Fang-Yu Fan, Hsin-Hua Chou, Wei-Chun Lin, Chiung-Fang Huang, Yi Lin, Yung-Kang Shen, Muhammad Ruslin
Summary: This study investigated the uniformity of illuminance field distributions in light guide plates (LGPs) by designing microstructures and optimizing the fabrication process. LGPs with microstructures and optimal design showed better uniformity in illuminance compared to those without microstructures, with an average illuminance of approximately 196.1 cd/m(2). The uniformity of LGPs with microstructures and optimal design was roughly 86.4%, nearly 1.65 times that of LGPs without microstructures.
Article
Chemistry, Physical
Sara Liparoti, Giorgia De Piano, Rita Salomone, Roberto Pantani
Summary: Micro-injection molding is a widely-used process for manufacturing plastic parts in the microscale. Weld lines, especially in the presence of junctions, have been a challenge in micro-injection molding. This study investigates the influence of mold temperature on weld line position and strength through experimental and simulation approaches, finding that higher mold temperatures lead to shorter weld lines and increased tensile modulus.
Article
Polymer Science
Rossella Surace, Vito Basile, Vincenzo Bellantone, Francesco Modica, Irene Fassi
Summary: This study evaluated the feasibility of an AM/mu-IM process chain by designing and fabricating mold inserts using SLA technology, which were experimentally tested. The results confirm that producing mu-IM parts with an SLA fabricated mold insert is feasible, but requires high accuracy in material selection, mold design, fabrication, and assembly.
Article
Materials Science, Multidisciplinary
Alex Hamilton, Jack Perris, Neil Convery, Daniel M. Mulvihill, Nikolaj Gadegaard
Summary: This paper presents an alternative method to electroplating, utilizing a nanoimprint route to produce flexible micro-structured polymer inserts for mold production. The optimized fabrication approach using silicon masters with smooth sidewalls successfully replicated aspect ratios of 1 and below, as well as feature spacings down to 20 micrometers. Parts were successfully ejected with retained nanometer scalloping, although inlay damage occurred after multiple replicas. Overall, a proof-of-concept microfluidic device was successfully produced, demonstrating the efficiency and cost-effectiveness of this approach for rapid prototyping of complex micro-structured designs.
MACROMOLECULAR MATERIALS AND ENGINEERING
(2021)
Article
Optics
Hongqiang Li, Yingjie Wang, Yaqiang Sun, Sai Zhang, Zhixuan An, Shanshan Zhang, Cheng Zhang, Zanyun Zhang, Quanhua Mao, Juan Daniel Prades Garcia
Summary: In this study, we investigated and lubricated 1 x 8 and 1 x 16 traditional/saddle arrayed waveguide grating (AWG) wavelength division multiplexing devices on flexible substrates. Chemical modification of the PDMS material was proposed to enhance the film-forming characteristics of the SU-8 core layer on PDMS substrates. The experimental results showed that the saddle-type AWGs had good signal transmission characteristics and lower insertion losses.
Article
Robotics
Leonard G. Guex, Lewis S. Jones, A. Xavier Kohll, Roland Walker, Mirko Meboldt, Volkmar Falk, M. Schmid Daners, Wendelin J. Stark
Summary: This work presents an injection molded soft total artificial heart made from high-temperature vulcanizing silicone, which exhibited a total cardiac output of over 16 L/min and could be continuously pumped for 110,000 actuation cycles. Using finite element analysis, stress concentrations within the artificial heart were identified, leading to an optimized design proposal.
Article
Polymer Science
Zhiguo Ma, Zheng Li, Ming Huang, Chuntai Liu, Changyu Shen, Xinyu Wang
Summary: This study investigates the effect of insert technology on improving the appearance quality of injection-molded products. By introducing inserts with different shapes into the runner system, the appearance quality is improved. The rectangular insert design scheme shows the best result.
Article
Polymer Science
Vincenzo Bellantone, Rossella Surace, Irene Fassi
Summary: This paper proposes the use of surface parameters as a quality index for evaluating micro injection molded products. The results of the study show that surface parameters evaluated in critical areas of the components can provide reliable estimates of surface quality for the molded parts.
Article
Materials Science, Multidisciplinary
Leonardo Piccolo, Kyle Puleo, Marco Sorgato, Giovanni Lucchetta, Davide Masato
Summary: In this study, a comprehensive multiscale model was developed to investigate the replication quality of laser-induced periodic surface structures by micro injection molding of different bio-based polymers. The modeling approach considered parameters such as topography, polymer rheology, thermal behavior, and mold surface energy, along with the influence of mold temperature on replication accuracy. The maximum error of 8% demonstrated the accuracy of the multi-scale model.
MATERIALS & DESIGN
(2021)
Article
Materials Science, Multidisciplinary
Al Basir, Abu Bakar Sulong, Nashrah Hani Jamadon, Norhamidi Muhamad, Ukwueze Bonaventure Emeka
Summary: Powder injection molding (PIM) has evolved into micro-powder injection molding (mu PIM) and become a key manufacturing technique for producing components in electronic, automobile, and biomedical fields. This article reviews the important process parameters for fabricating parts with different materials using these techniques, and provides a brief discussion on future research guidelines in two-component macro and micro powder injection molding.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Polymer Science
Rossella Surace, Claudia Pagano, Vincenzo Bellantone, Simone Gatti, Leonardo Castellani, Massimo Vighi, Gregory Stoclet, Sara Sechi, Irene Fassi, Francesco Baldi
Summary: This study investigated the moldability and microstructural characteristics of nano-filled PA6 based systems via micro-injection molding compared to traditional injection molding. Different thermomechanical histories during the two molding processes led to different microstructures in the micro- and macro-parts, influenced by the type of filler. The presence of nano-fillers did not hinder the mold replication capability of PA6 in micro-injection molding.
Article
Optics
I. Gnilitskyi, W. Alnusirat, M. Sorgato, L. Orazi, G. Lucchetta
Summary: In this study, the influence of two different types of laser-induced periodic surface structures on the flow length in micro injection molding was evaluated. The performance of an untreated cavity surface was compared with surfaces modified by LIPSS. The phenomenon was investigated by localizing the weld lines created by the polymer flow in different surface treatments.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Polymer Science
Wu Guo, Zhaogang Liu, Yan Zhu, Li Li
Summary: Based on a self-designed pan-mill mechanochemical reactor, a PVDF/GP nano-composite powder with high beta-phase content was prepared for micro-injection molding, resulting in micro-parts with good replication and dimensional stability. The high injection speed and small cavity of micro-injection molding induced a skin-core structure and increased crystallinity, leading to improved dielectric properties and mechanical strength of the micro-parts.
