On the porosity of advanced pore morphology structures

Kovačič, Aljaž; Ren, Zoran

doi:10.1016/j.compstruct.2016.09.046

Cited by 9 publications

(4 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Capillary pressure can hinder or promote the osmotic flow in fiber bundles, resulting in the formation of pores in or between fiber bundles. The porosity in the composite material will seriously affect the mechanical properties of the parts, such as bending strength and fatigue strength [ 28 , 29 , 30 , 31 , 32 ]. Therefore, it is necessary to further study the influencing mechanism of capillary pressure on dual-scale infiltration so that the balance can be achieved through the flow front, and the porosity of the molded part can be reduced to improve the mechanical properties.…”

Section: Introductionmentioning

confidence: 99%

A General and Efficient Approach for the Dual-Scale Infiltration Flow Balancing in In Situ Injection Molding of Continuous Fiber Reinforced Thermoplastic Composites

Liang

2021

Polymers

View full text Add to dashboard Cite

In situ injection molding of continuous fiber reinforced thermoplastic composites is challenged by unbalanced dual-scale infiltration flow due to the pronounced capillary effect. In this paper, a general and efficient approach was proposed for dual-scale infiltration flow balancing based on numerical simulation. Specifically, Stokes and Brinkman equations were used to describe the infiltration flow in inter- and intra-fiber bundles. In particular, capillary pressure drop was integrated in the Brinkmann equation to consider the capillary effect. The infiltration flow front is tracked by the level set method. Numerical simulation and experimental results indicate that the numerical model can accurately demonstrate the unbalanced infiltration flow in inter- and intra-fiber bundles caused by the changes of the injection rate, the resin viscosity, the injection rate, the fiber volume fraction and the capillary number. In addition, the infiltration flow velocity in inter- and intra-fiber bundles can be efficiently tuned by the capillary number, which is mainly determined by the injection rate for a specified resin system. The optimal capillary numbers obtained by simulation and experiment are 0.022 and 0.026, which are very close to each other. Finally, one-dimensional in situ injection molding experiments with constant injection pressure were conducted to prepare fiber reinforced polymerized cyclic butylene terephthalate composite laminate with various flow rates along the infiltration direction. The experimental results confirmed that the lowest porosity and the highest interlaminar shear strength of the composite can only be obtained with the optimized capillary number, which is basically consistent with the simulation results.

show abstract

Section: Introductionmentioning

confidence: 99%

A General and Efficient Approach for the Dual-Scale Infiltration Flow Balancing in In Situ Injection Molding of Continuous Fiber Reinforced Thermoplastic Composites

Liang

2021

Polymers

View full text Add to dashboard Cite

show abstract

“…Studies have been carried out to determine the response of these structures exposed to compressive stresses (Hohe et al, 2012;Kovačič and Ren, 2016). Kovačič and Ren (2016), developed a theory to estimate the lower and upper limit values of partial and total porosities in composite materials constituted by APM distributions. This theory includes the error estimation assuming negligible the adhesive phase action in the APM element.…”

Section: Introductionmentioning

confidence: 99%

Análisis estático y dinámico de estructuras sándwich con núcleo monocapa de esferoides APM espumados in-situ con mármol

et al. 2020

View full text Add to dashboard Cite

En el presente trabajo se estudia el comportamiento mecánico de las espumas de aluminio mediante la realización de pruebas estáticas y dinámicas de compresión. Una vez que se haya analizado su comportamiento, se debe poder decidir si este material es el adecuado para diferentes tipos de aplicaciones. Se comienza empleando piezas esferoidales de aleación de aluminio AlSi7, espumadas con mármol como agente de soplado, situadas entre dos placas de aluminio fijadas a las bolas con una mezcla formada por resina y un endurecedor. Por otro lado, se preparan otros paneles sándwiches con espumas de aluminio convencionales, adheridos con la misma mezcla a dos placas de aluminio. Estos dos tipos de materiales serán caracterizados mecánicamente.

show abstract

“…The mechanical and thermal properties of APM structures depend strongly on the complex internal geometry of the APM foam elements, as is known for other closed-cell foams [24]. In [25] the authors studied the porosity of individual APM elements and the porosity of the bulk APM structures theoretically. The experimental structural characterization of these APM foam elements is reported in [3].…”

Section: Introductionmentioning

confidence: 99%

Characterization of Geometrical Changes of Spherical Advanced Pore Morphology (APM) Foam Elements during Compressive Deformation

et al. 2019

Self Cite

View full text Add to dashboard Cite

The mechanical properties of Advanced Pore Morphology (APM) foam elements depend strongly upon their internal porous and external structural geometry. This paper reports on a detailed investigation of external (e.g. shape and size) and internal (e.g. distribution, size, number of pores) geometry and porosity changes of APM foam elements, during compressive loading by means of the ex-situ micro-Computed Tomography, and advanced digital image analysis and recognition. The results show that the porosity of APM foam elements decreases by only 25% at the engineering strain of 70% due to an increase of the number of pores at high stages of compressive deformation. The APM foam elements also exhibit a positive macroscopic Poisson’s ratio of υ = 0.2, which is uncharacteristic for cellular structures.

show abstract

On the porosity of advanced pore morphology structures

Cited by 9 publications

References 12 publications

A General and Efficient Approach for the Dual-Scale Infiltration Flow Balancing in In Situ Injection Molding of Continuous Fiber Reinforced Thermoplastic Composites

A General and Efficient Approach for the Dual-Scale Infiltration Flow Balancing in In Situ Injection Molding of Continuous Fiber Reinforced Thermoplastic Composites

Análisis estático y dinámico de estructuras sándwich con núcleo monocapa de esferoides APM espumados in-situ con mármol

Characterization of Geometrical Changes of Spherical Advanced Pore Morphology (APM) Foam Elements during Compressive Deformation

Contact Info

Product

Resources

About