Date:  Thursday, May 22, 2008
Time: 10:00 am
Location:  NIA headquarters, 100 Exploration Way, Room 137
Speaker: Prof. Pascal Hubert, McGill University, Montreal, Quebec, Canada

Subject:  “Integrated Design and Manufacturing of a Composite Helicopter Horizontal Stabilizer Slat”

ABSTRACT: 
This paper presents an integrated design and manufacturing approach for the production of a carbon fibre epoxy helicopter horizontal stabilizer slat using the resin transfer moulding (RTM) process.  In order to optimize the composite component, processing development and structural analysis are integrated.  The processing development consists of a complete material characterization followed by mould filling simulations and prediction of the component final cure and dimensions.  The evolution of material properties during the manufacturing, such as the degree of cure, the chemical shrinkage and the elastic modulus allows the prediction of the residual stresses during processing and the process induced part distortions. These results are integrated to optimize the design and the RTM manufacturing process. The structural analysis involves the prediction of the final failure of the composite part under static and fatigue loadings.  The paper also presents the results of the manufacturing of prototype components that validated the design obtained by the analysis.  This effort is an example of the benefit of academia-industry-government collaboration through the Consortium for Research and Innovation in Aerospace in Quebec (CRIAQ).

Dr. Pascal Hubert (P. Metals and Materials Engineering, University of British Columbia) holds a Canada Research Chair (Tier II) in Advanced Composite Materials.  He is an associate professor at McGill University in the Department of Mechanical Engineering since September 2002.  Before coming back to Canada, Dr. Hubert was leading the process modelling research at the Advanced Material and Processes Branch at NASA Langley Research Center in Hampton, VA.    Dr. Hubert is a co-founder and director of Convergent Manufacturing Technologies Inc., a university spin-off company specialized in software development for composites process simulation.  At McGill University, he is leading a dynamic group of 1 research associate, 1 postdoctoral fellow, 7 Ph.D. and 7 Masters students involved in the development of process modelling for polymer composite structures and on the optimization of carbon nanotube (CNT) composite properties. Dr. Hubert as 90 referred journal and conference publications with over 20 publications in the area of nanocomposites.  He also gave several presentations on the modelling of CNT polymer composites at conferences, universities and industries. 

Dr. Hubert’s research focuses on the processing and performance of composite materials.  His research activities include:

• Process Modelling of Polymer Composites:  Processing models are developed in order to understand and optimize the manufacturing of composite materials.  These models use the finite element method and simulate the physical phenomena found during the processing of polymer composite materials (i.e. thermal, chemical, flow and residual stress development).

• Investigation of Processing-Performance Relationship:  The design of composite structures is intimately linked to the processing cycle used.  It is critical to understand the relationship between processing and the performance (mechanical, surface finish) of the final composite part.

• Development of Polymer Nanocomposites:  This new class of composite materials consists of polymers reinforced with particles a few nanometres in size (e.g. carbon nanotubes, nanoclays).  The properties of these composite materials are predicted using new numerical approaches that combine molecular dynamics and continuum mechanics.

• Development of Polymer Composites Characterization Techniques:  In order to apply process modelling, numerous material properties must be measured.  The resin curing behaviour is correlated with other changes in other properties (e.g. viscosity, cure shrinkage, elastic modulus).  Fibre preforms used in composite materials are also characterized to obtain the permeability and compaction as a function of fibre architecture and volume fraction.

In order to effectively pursue this research program, an extensive network of collaborators has been developed.  Dr. Hubert is currently involved in active collaborative research programs in the area of composite processing and nanotechnology with NASA Langley Research Center, Michigan State University with Prof. Alfred Loos and Purdue University with Prof. Byron Pipes.  Strong existing partnership with Prof. Anoush Poursartip, Prof. Reza Vaziri and Prof. Göran Fernlund at The University of British Columbia in the area of development of composites processing simulation tools will be strengthened with several planned collaborative projects.  Two CFI grants were obtained to acquire the composite manufacturing equipment for The Composite Materials and Structures Laboratory at McGill University.  A partnership with Prof. François Trochu and Prof. Eduardo Ruiz at Ecole Polytechnique de Montreal is well established in the area of resin transfer moulding for aerospace and automotive applications.  He also has several active collaborations with the National Research Council (NRC) Institute of Aerospace Research in Ottawa and in Montreal with Dr. Andrew Johnston and Dr. Ali Yousefpour.  Collaboration in the area of nanotechnology and thermoplastic processing research is active with the NRC Industrial Materials Institute in Boucherville with Dr. Johanne Denault.  Recently, a very promising collaboration with Dr. Benoit Simard of the NRC Steacie Institute for Molecular Sciences was initiated in the area of carbon nanotube polymer composites.  Finally, strong industry collaborations with Bell Helicopter, Boeing Canada, Bombardier, MDA Co. and Ford Motor Co. on several research projects have created the necessary focus for the research conducted by his group.