Experimental and numerical investigations of cavity filling process in injection moulding for microcantilever structures

Kim, Won Woo; Gang, Myeong Gu; Min, Byung Kwon; Kim, Wook Bae

doi:10.1007/s00170-014-6104-0

Cited by 30 publications

(16 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The filling process in micro injection moulding is more complex because of peculiar phenomena happening at the micro scale such as high heat transfer at the melt-mould wall interface, presence of wall slip, influence of surface tension, compressibility of the melt and pressure-dependent viscosity. All the aspects that have been reported are affecting μIM at levels that are different from those encountered in injection moulding of conventionally-sized components [ 2 ].…”

Section: Introductionmentioning

confidence: 99%

Effect of Process Parameters on Flow Length and Flash Formation in Injection Moulding of High Aspect Ratio Polymeric Micro Features

et al. 2018

View full text Add to dashboard Cite

This paper reports an investigation of the effects of process parameters on the quality characteristics of polymeric parts produced by micro injection moulding (μIM) with two different materials. Four injection moulding process parameters (injection velocity, holding pressure, melt temperature and mould temperature) were investigated using Polypropylene (PP) and Acrylonitrile Butadiene Styrene (ABS). Three key characteristics of the mouldings were evaluated with respect to process settings and the material employed: part mass, flow length and flash formation. The experimentation employs a test part with four micro fingers with different aspect ratios (from 21 up to 150) and was carried out according to the Design of Experiments (DOE) statistical technique. The results show that holding pressure and injection velocity are the most influential parameters on part mass with a direct effect for both materials. Both parameters have a similar effect on flow length for both PP and ABS at all aspect ratios and have higher effects as the feature thickness decreased below 300 μm. The study shows that for the investigated materials the injection speed and packing pressure were the most influential parameters for increasing the amount of flash formation, with relative effects consistent for both materials. Higher melt and mould temperatures settings were less influential parameters for increasing the flash amount when moulding with both materials. Of the two investigated materials, PP was the one exhibiting more flash formation as compared with ABS, when corresponding injection moulding parameters settings for both materials were considered.

show abstract

Section: Introductionmentioning

confidence: 99%

Effect of Process Parameters on Flow Length and Flash Formation in Injection Moulding of High Aspect Ratio Polymeric Micro Features

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Micro‐injection molding is a widely used polymers processing method for fabricating micro polymer parts because of the advantages such as low manufacturing cost, short production cycle, good repeatability and simple process . Based on the experimental research and theoretical analysis, due to the high velocity, high pressure and micro scale flow conditions in micro‐injection molding process, the melt flow will exhibit uneven and complex changes in the micro cavity, the no‐slip boundary condition is not yet valid, and the wall slip behavior will occur . Compared with the shear stress in conventional size cavity, the shear stress increases sharply at the wall of the micro cavity during micro‐injection molding, and the possibility of the wall shear stress exceeding the critical value and the occurrence of wall slip is higher in mold filling process .…”

Section: Introductionmentioning

confidence: 99%

Wall Slip of Linear Polymer Melts During Ultrasonic‐assisted Micro‐injection Molding

Gao

Qiu

Ouyang

et al. 2018

Polymer Engineering & Sci

View full text Add to dashboard Cite

The wall slip of linear polymer melts under ultrasonic vibration is investigated by correcting the slip mechanism, and melt flow behaviors in ultrasonic‐assisted micro‐injection molding (UμIM) method are discussed. Based on the effect mechanism of ultrasonic vibration on the melt, theoretical models of the critical shear stresses for the onset of weak and strong wall slip during UμIM are established, and the change in rheological properties due to the onset of wall slip under ultrasonic vibration is experimental investigated by a built measurement system. The results show that the onset of weak and strong wall slip of the melt in micro cavity are promoted by ultrasonic vibration, which agree with the built theoretical models, and the melt filling capability in micro cavity is enhanced by reducing apparent viscosity and releasing shear stress of the polymer melt, which improves the molding quality of micro polymer parts via UμIM method. POLYM. ENG. SCI., 59:E7–E13, 2019. © 2018 Society of Plastics Engineers

show abstract

“…In this study, three processing parameters were chosen: mould temperature (T m ), holding pressure (P h ), and injection speed (V i ), based on our previous work and other previously published studies (Kim et al 2014;Attia et al 2009;Lucchetta et al 2014). The melt temperature was fixed at the recommended value set by the material supplier considering the thermal stability of the POM material.…”

Section: Moulding Conditionsmentioning

confidence: 99%

Microinjection moulding of miniaturised polymeric ortho-planar springs

Han

Kim

2015

Microsyst Technol

Self Cite

View full text Add to dashboard Cite

show abstract

Experimental and numerical investigations of cavity filling process in injection moulding for microcantilever structures

Cited by 30 publications

References 29 publications

Effect of Process Parameters on Flow Length and Flash Formation in Injection Moulding of High Aspect Ratio Polymeric Micro Features

Effect of Process Parameters on Flow Length and Flash Formation in Injection Moulding of High Aspect Ratio Polymeric Micro Features

Wall Slip of Linear Polymer Melts During Ultrasonic‐assisted Micro‐injection Molding

Microinjection moulding of miniaturised polymeric ortho-planar springs

Contact Info

Product

Resources

About