Modified Lap Shear Test for Automated Fiber Placement (AFP) of Steered Thermoplastic Composite Tape

Abstract Laser-assisted automated fiber placement (AFP) is highly suitable for an efficient production of thermoplastic-matrix composite parts, especially for aeronautic/aerospace applications. Heat input by laser heating provides many advantages such as better temperature controls and uniform heating projections. However, this laser beam distribution can be affected by the AFP head system, mainly at the roller level. In this paper, a new optico-thermal model is established to evaluate the laser energy quantity absorbed by a poly(ether ether ketone) reinforced with carbon fibers (APC-2). During the simulation process, the illuminated radiative material properties are characterized and evaluated in terms of the roller deformation, the tilt of the robot head, and the reflection phenomenon between the substrate and the incoming tape. After computing the radiative source term using a ray-tracing method, these data are used to predict the temperature distribution on both heated surfaces of the composite during the process. The results show that both the roller deformation and the tilt of head make it possible to focus the laser beam on a small area, which considerably affects the quality of the finished part. These findings demonstrate that this optico-thermal model can be used to predict numerically the insufficient heating area and thermoplastic composites heating law.

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Mechanical property evaluation of nano‐silver paste sintered joint using lap‐shear test

Soldering & Surface Mount Technology ◽

10.1108/09540911211214695 ◽

2012 ◽

Vol 24 (2) ◽

pp. 120-126 ◽

Cited By ~ 21

Author(s):

Xin Li ◽

Gang Chen ◽

Xu Chen ◽

Guo‐Quan Lu ◽

Lei Wang ◽

...

Keyword(s):

Mechanical Property ◽

Shear Test ◽

Silver Paste ◽

Nano Silver ◽

Lap Shear ◽

Property Evaluation ◽

Lap Shear Test

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

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717738305 ◽

2017 ◽

Vol 31 (12) ◽

pp. 1676-1725 ◽

Cited By ~ 15

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.

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LAP SHEAR TEST OF A MAGNESIUM FRICTION SPOT JOINT: NUMERIC MODELING

Tecnologia em Metalurgia Materiais e Mineração ◽

10.4322/tmm.2013.014 ◽

2013 ◽

Vol 10 (2) ◽

pp. 97-102 ◽

Cited By ~ 1

Author(s):

Leonardo Contri Campanelli ◽

Armando Ítalo Sette Antonialli ◽

Nelson Guedes de Alcântara ◽

Claudemiro Bolfarini ◽

Uceu Fuad Hasan Suhuddin ◽

...

Keyword(s):

Shear Test ◽

Lap Shear ◽

Lap Shear Test ◽

Numeric Modeling

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