Processing of thermoplastic matrix composites through automated fiber placement and tape laying methods

2017 ◽  
Vol 31 (12) ◽  
pp. 1676-1725 ◽  
Author(s):  
Khaled Yassin ◽  
Mehdi Hojjati
Keyword(s):  
Heat Transfer ◽  
Quality Parameters ◽  
Thermoplastic Composites ◽  
Transfer Model ◽  
Scanning Calorimetry ◽  
Intimate Contact ◽  
Fiber Placement ◽  
Hot Gas ◽  
Lap Shear ◽  
Automated Fiber Placement

Fiber-reinforced composite materials are replacing metallic components due to their higher specific strength and stiffness. Automation and thermoplastics emerged to overcome the time and labor intensive manual techniques and the long curing cycles associated with processing thermoset-based composites. Thermoplastics are processed through fusion bonding which involves applying heat and pressure at the interface. Together with automated techniques (such as automated fiber placement, and automated tape laying), a fast, clean, out-of-autoclave, and automated process can be obtained. A detailed review of thermoplastic composites processing through automated methods is presented. It sheds the light on the materials used and the different heat sources incorporated with the pros and cons of each, with concentration mainly on hot gas torch, laser, and ultrasonic heating. A thorough illustration of the several mechanisms involved in a tow/tape placement process is tackled such as heat transfer, intimate contact development, molecular interdiffusion, void consolidation and growth, thermal degradation, crystallization, and so on. Few gaps and recommendations are included related to materials, laser heat source, heat transfer model, and the use of silicone rubber rollers. A review of optimization studies for tape placement processes is summarized including the main controllable variables and product quality parameters (or responses), with some of the major findings for laser and hot gas torch systems being presented. Both mechanical and physical characterizations are also reviewed including several testing techniques such as short beam shear, double cantilever beam, lap shear, wedge peel, differential scanning calorimetry, and so on. Challenges, however, still exist, such as achieving the autoclave-level mechanical properties and complying with the porosity levels required by the aerospace industry. More work is still necessary to overcome these challenges as well as increase the throughput of the process before it can be totally commercialized.

scholarly journals Heat transfer analysis of automated fiber placement of thermoplastic composites using a hot gas torch

2019 ◽  
Vol 5 (4) ◽  
pp. 206-223 ◽  
Author(s):  
Omid Aghababaei Tafreshi ◽  
Suong Van Hoa ◽  
Farjad Shadmehri ◽  
Duc Minh Hoang ◽  
Daniel Rosca
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Analysis ◽  
Thermoplastic Composites ◽  
Fiber Placement ◽  
Hot Gas ◽  
Automated Fiber Placement

EFFECT OF THERMAL INPUT ON THE TEMPERATURE DISTRIBUTION OF THERMOPLASTIC COMPOSITES MADE BY AUTOMATED FIBER PLACEMENT (AFP)

2021 ◽  
Author(s):  
MEHRSHAD MOGHADAMAZAD ◽  
SUONG V. HOA
Keyword(s):  
Thermoplastic Composite ◽  
Heat Transfer Analysis ◽  
Thermoplastic Composites ◽  
Experimental Measurements ◽  
Convection Coefficient ◽  
Fiber Placement ◽  
Hot Gas ◽  
Temperature Distributions ◽  
Automated Fiber Placement ◽  
Theoretical Results

The heat transfer analysis of thermoplastic composite manufactured using automated fiber placement with a hot gas torch can be done using numerical methods such as finite difference method. The accuracy of the theoretical results depends upon the accuracy of the thermal inputs. The hot gas/air temperature and convection coefficient distributions between the hot gas and the surface of the substrate (thermal inputs) have the significant influence on the accuracy of the resulting theoretical temperature distributions in the deposited laminate. A model predicting theoretical results which agree with experimental measurements is presented

Determination of convective heat transfer coefficient for hot gas torch (HGT)-assisted automated fiber placement (AFP) for thermoplastic composites

2021 ◽  
pp. 089270572098236
Author(s):  
Lorenz Zacherl ◽  
Farjad Shadmehri ◽  
Klemens Rother
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Heat Transfer Analysis ◽  
Thermoplastic Composites ◽  
Hot Gas ◽  
Automated Fiber Placement

In-situ manufacturing of thermoplastic composites using the automated fiber placement (AFP) process consists of heating, consolidation and solidification steps. During the heating step using hot gas torch (HGT) as a moving heat source, the incoming tape and the substrate are heated up to a temperature above the melting point of the thermoplastic matrix. The convective heat transfer occurs between the hot gas flow and the composites in which the convective heat transfer coefficient h plays an important role in the heat transfer mechanism which in turn significantly affects temperature distribution along the length, width and through the thickness of the deposited layers. Temperature is the most important process parameter in AFP in-situ consolidation that affects bonding quality, crystallization and consolidation. Although it is well known the convective heat transfer coefficient h is not constant and has a distribution, most studies have assumed a constant value for h for heat transfer analysis which leads to discrepancy between numerical and experimental results. In this study a new function is proposed to approximate the distribution of the convective heat transfer coefficient h in the vicinity of the nip point. Using the proposed convective heat transfer coefficient distribution, a three-dimensional finite element transient heat transfer analysis is performed to predict temperature distribution in the composite parts. An optimization loop is employed to find the free parameters of the distribution function so that the predicted temperature match experimental data. It is shown that, unlike other studies assuming constant h value, not only maximum temperature can be well predicted, but also predicted heating and cooling curves agree well with experimental results. The cooling rate is of significant importance in crystallization behavior and residual stress calculation.

Thermal stresses in rings of thermoplastic composites made by automated fiber placement process

2011 ◽  
Vol 18 (1-2) ◽  
pp. 35-49 ◽  
Author(s):  
Qi Zhao ◽  
Suong V. Hoa ◽  
Zhan Jun Gao
Keyword(s):  
Heat Transfer ◽  
Thermal History ◽  
Thermal Stresses ◽  
Thermoplastic Composite ◽  
Thermoplastic Composites ◽  
Thermally Induced ◽  
Fiber Placement ◽  
Ansys Simulation ◽  
Hot Air ◽  
Automated Fiber Placement

AbstractThe automated fiber placement (AFP) of thermoplastic composites has a complex thermal history, which seriously leads to residual stresses in the products. An ANSYS simulation model is proposed to predict thermal history and induced thermal stresses in thermoplastic composite rings. It attempts to simulate closely the AFP process by adding materials incrementally. The processing speed was modeled by incrementally moving the hot air heater along the outer surface of the composite cylinder. The analysis is time-dependent, including two steps of transient heat transfer and induced thermal stress analyses. The heat transfer characteristics and the accumulated thermal effect during processing are investigated. Thermally induced stresses are examined.

Processing and characterization of the thermoplastic composites manufactured by ultrasonic vibration–assisted automated fiber placement

2017 ◽  
Vol 31 (3) ◽  
pp. 339-358 ◽  
Author(s):  
Qiyi Chu ◽  
Yong Li ◽  
Jun Xiao ◽  
Dajun Huan ◽  
Xiangyang Zhang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Impact Toughness ◽  
Ultrasonic Vibration ◽  
High Efficiency ◽  
Thermoplastic Composites ◽  
Hot Press ◽  
Scanning Calorimetry ◽  
Fiber Placement ◽  
Automated Fiber Placement ◽  
The Impact

To obtain the autoclave-level mechanical properties using in situ consolidation of thermoplastic composites by automated fiber placement (AFP) with high efficiency is the focus of recent research. Different heat resources were utilized to pursue improved mechanical properties and deposition rates but yet not very satisfactory. In this article, E-glass fiber/polypropylene laminates, manufactured by ultrasonic vibration–assisted AFP (UAFP) and autoclave, were compared by means of mechanical properties and crystallization. The interfacial bonding mechanism was analyzed theoretically based on the principle of ultrasonic heating and the autohesion. The orthogonal tests were designed to study the effect of the process parameters on the interlaminar shear strength (ILSS), including the ultrasonic amplitude, layup speed, and pressure, to optimize the manufacturing process of specimens. The mechanical tests and differential scanning calorimetry (DSC) were utilized to evaluate the ILSS, mode I interlaminar fracture toughness GIC, impact toughness, and degree of crystalline of laminates from hot-press and UAFP. The experimental results indicate that the ILSS of the specimens from UAFP can match with the hot-press specimens. The GIC and the impact toughness of the UAFP specimens are 59.9% and 20.1% lower than the hot-press ones, respectively, which are due to the lower degree of crystalline caused by the higher cooling rate during the UAFP process. The results of DSC show that the crystallinity of specimens made from UAFP is only 38.5%, whereas the 49.2% crystallinity is tested for the hot-press.

scholarly journals Review: Filament Winding and Automated Fiber Placement with In Situ Consolidation for Fiber Reinforced Thermoplastic Polymer Composites

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1951
Author(s):  
Yi Di Boon ◽  
Sunil Chandrakant Joshi ◽  
Somen Kumar Bhudolia
Keyword(s):  
Processing Parameters ◽  
Filament Winding ◽  
Reference Points ◽  
Thermoplastic Composites ◽  
Manufacturing Processes ◽  
Fiber Reinforced ◽  
Consolidation Process ◽  
Fiber Placement ◽  
Automated Fiber Placement

Fiber reinforced thermoplastic composites are gaining popularity in many industries due to their short consolidation cycles, among other advantages over thermoset-based composites. Computer aided manufacturing processes, such as filament winding and automated fiber placement, have been used conventionally for thermoset-based composites. The automated processes can be adapted to include in situ consolidation for the fabrication of thermoplastic-based composites. In this paper, a detailed literature review on the factors affecting the in situ consolidation process is presented. The models used to study the various aspects of the in situ consolidation process are discussed. The processing parameters that gave good consolidation results in past studies are compiled and highlighted. The parameters can be used as reference points for future studies to further improve the automated manufacturing processes.

Sign in / Sign up

Export Citation Format

Share Document