TY - JOUR

T1 - Experimental Investigation on the Use of a PEI Foam as Core Material for the In-Situ Production of Thermoplastic Sandwich Structures Using Laser-Based Thermoplastic Automated Fiber Placement

AU - Denkena, Berend

AU - Schmidt, Carsten

AU - Schmitt, Christopher

AU - Kaczemirzk, Maximilian

N1 - Funding Information: The authors thankfully acknowledge the financial and organizational support of the project JoinTHIS (ZW6-85024403) by the federal state of Lower Saxony and the European Regional Development Fund (ERDF). The publication of this article was funded by the Open Access Fund of the Leibniz Universität Hannover.

PY - 2022/10

Y1 - 2022/10

N2 - Laser-based thermoplastic automated fiber placement (TAFP) is nowadays mainly used to produce pure carbon fiber-reinforced plastic (CFRP) structures. This paper investigates the feasibility of a novel application: The deposition of thermoplastic prepreg tapes onto a thermoplastic foam for the production of thermoplastic sandwich structures. Therefore, simple deposition experiments of thermoplastic PEEK/CF prepreg tapes on a PEI closed-cell foam were carried out. 3D surface profile measurements and peel tests according to DIN EN 28510-1 standard were used to investigate the joining area and bonding quality. The results show that a cohesive bond is formed between the deposited tapes and the foam core, however the foam structure in the area of the deposited tapes deforms in dependence of the process parameters, and increasingly with higher deposition temperatures. Due to the deformations that occur during tape deposition, the thermomechanical foam behavior under the TAFP process conditions was investigated in more detail in a subsequent study for an extensive parameter space using a simple experimental setup. Results show that for suitable process parameters, namely a short contact time and a high temperature, the foam deformation can be minimized with the simultaneous formation of a thin melting layer required for cohesive bonding. The inner foam core structure remains unaffected.

AB - Laser-based thermoplastic automated fiber placement (TAFP) is nowadays mainly used to produce pure carbon fiber-reinforced plastic (CFRP) structures. This paper investigates the feasibility of a novel application: The deposition of thermoplastic prepreg tapes onto a thermoplastic foam for the production of thermoplastic sandwich structures. Therefore, simple deposition experiments of thermoplastic PEEK/CF prepreg tapes on a PEI closed-cell foam were carried out. 3D surface profile measurements and peel tests according to DIN EN 28510-1 standard were used to investigate the joining area and bonding quality. The results show that a cohesive bond is formed between the deposited tapes and the foam core, however the foam structure in the area of the deposited tapes deforms in dependence of the process parameters, and increasingly with higher deposition temperatures. Due to the deformations that occur during tape deposition, the thermomechanical foam behavior under the TAFP process conditions was investigated in more detail in a subsequent study for an extensive parameter space using a simple experimental setup. Results show that for suitable process parameters, namely a short contact time and a high temperature, the foam deformation can be minimized with the simultaneous formation of a thin melting layer required for cohesive bonding. The inner foam core structure remains unaffected.

KW - additive manufacturing

KW - in-situ

KW - PEI foam

KW - thermoplastic automated fiber placement

KW - thermoplastic sandwich composites

KW - VCSEL

UR - http://www.scopus.com/inward/record.url?scp=85140969622&partnerID=8YFLogxK

U2 - 10.3390/ma15207141

DO - 10.3390/ma15207141

M3 - Article

AN - SCOPUS:85140969622

VL - 15

JO - Materials

JF - Materials

SN - 1996-1944

IS - 20

M1 - 7141

ER -