Processing effect on the mechanical properties of randomly-oriented strands thermoplastic composites


Student: Benoit Landry - PhD student

Supervisor: Prof. Pascal Hubert

Sponsors:  Bell Helicopter Textron Canada Limited; Bombardier Inc.; Pratt and Whitney Canada Corp.; Marquez; Transtech Limited; Delastek Inc.; Avior Integrated Products Inc.; NRC; CRIAQ; NSERC

Randomly-Oriented Strands (ROS) composites are a bulk moulding compound type of material made of strands of unidirectional pre-impregnated tape. The main advantage of these materials is their great formability compared to continuous fibre composites, which are generally limited to components having small curvature and thickness variations. ROS composites are intended to be used for small intricate compression moulded components having features such as varying wall thickness, tight radii, reinforcing ribs, mould-in holes, etc. The objective of this project is to relate the processing parameters, such as moulding pressure and temperature, to the compaction quality and resulting mechanical properties of ROS composites. The focus will be placed on understanding how defects such as voids are formed, and quantifying their effect on the fracture properties of the material. This will provide processing guidelines for the manufacturing of thermoplastic ROS composites. Finite element modelling will also be employed to further understand how the material’s random nature affects its mechanical properties.

Randomly-Oriented Strands (ROS) composites.

Cross-sectional micrograph of a ROS composite sample processed at low pressure showing intralaminar voids.

Landry B and Hubert P. Processing effect on the damage tolerance of randomly-oriented strands thermoplastic composites. Proceeding of the 19th International Conference on Composite Materials, Montreal QC, Canada, 2013.

Selezneva L, Picher-Martel GP, Landry B et al. Compression moulding of discontinuous-fibre Carbon/PEEK composites: study of mechanical properties. Proceeding of the International SAMPE Symposium and Exhibition, Baltimore MD, USA, 2012.

Landry B, LaPlante G and Leblanc LR. Environmental effects on mode II fatigue delamination growth in an aerospace grade carbon/epoxy composite. Composites Part A: Applied Science and Manufacturing, 43(3):475-485, 2012.

Landry B and LaPlante G. Modeling delamination growth in composites under fatigue loadings of varying amplitudes. Composites Part B: Engineering, 43(2):533–541, 2012.

LaPlante G and Landry B. The effect of hygrothermal aging on mode I fatigue delamination growth in a carbon/epoxy composite. Journal of Advanced Materials, 43(2):79–86, 2011.

Landry B, LaPlante G, Maslouhi A. The effects of hygrothermal aging on mode II delamination propagation in G40-800/5276-1 graphite/epoxy composite. Eighth Joint Canada-Japan Workshop on Composites, Montreal QC, Canada, 2010.

LaPlante G and Landry B. The effect of hygrothermal aging on the delamination of a carbon/epoxy composite. Proceedings of the International SAMPE Symposium and Exhibition, Seattle WA, USA, 2010.