COMPLEX COMPOSITE TURBO-MACHINERY COMPONENT FABRICATED BY RESIN TRANSFER MOLDING

Open Access
Author:
Maruszewski, Rance Joel
Graduate Program:
Engineering Mechanics
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 30, 2011
Committee Members:
  • Dr Reginald Hamilton / Dr Kevin Koudela, Thesis Advisor
  • Kevin L Koudela, Thesis Advisor
  • Reginald Felix Hamilton, Thesis Advisor
Keywords:
  • Cost Saving Manufacturing Technology
  • Metrology
  • Geometric Inspection
  • Geometry Correction by Finite Element Modeling FEM
  • Fiber Reinforced Polymer FRP
  • Resin Transfer Molding RTM
  • Composite Fabrication
  • Prototype
  • Production
  • Urethane Tooling
  • Aluminum Tooling
  • Woven Carbon Fabric
  • Vinyl Ester Resin
Abstract:
This thesis is an overview of the resin transfer molding fabrication of a complex composite turbo-machinery component (blade). The motivation for this work was to provide an alternative cost saving technology for the manufacture of complex geometries. Legacy components were machined from metal blanks incurring high machining costs and long delivery times due to complex geometry, the degree of machining accuracy needed, and surface finish requirements of the part. A fabrication process technology was developed to produce an alternative low-cost high quality composite component with tailored properties. Beyond cost reduction, the main priorities of this process focused on quality and repeatability. Technology development took place in two phases: a prototype proving phase and a production phase. For the proving phase, a machined master blade was used to create a prototype urethane tooling mold. Hybrid fiber preforms were constructed from carbon and glass fabrics to fill the complex mold cavity. Preform layups were empirically generated and sewn together. Preforms were then loaded into the mold and the assembly was placed within a containment vessel. Vinyl ester resin was injected into the mold and allowed to cure. The mold was then disassembled and the blade extracted. The geometry of the as-fabricated prototype blade was inspected using a coordinate measuring machine. The prototype blade exhibited a geometric ‘inward bow’ distortion. Geometry data and lessons learned from the prototype phase influenced development of the production phase. On the foundation of a successful prototype part that proved development concepts, production tooling was designed and constructed from aluminum. A novel finite element geometry correction method was developed and demonstrated to correct for prototype blade distortion by modifying mold cavity geometry. These geometry corrections were implemented in the aluminum tooling. Also, small preforms were added, and other improvements made. A production blade was fabricated using the aluminum production tooling, inspected, and compared to the prototype and the design of record (DOR). The production tooling yielded an improved blade with corrected geometry, optimized fiber fill, and accurate repeatability. The overall manufacturing development was a success resulting in a robust low-cost resin transfer molding process for the repeatable production of high quality complex composite turbo-machinery components with sufficient geometric accuracy. Two main accomplishments are a fully developed production technology and a process engineering blueprint for developing complex composite resin transfer molding technologies. A third major achievement of this work was the successful application of the aforementioned finite element geometry correction method that accounted for material distortions to yield a part that met required tolerances. Included is a review of the resin transfer molding process covering studies on the effects of process variables, potential defects and countermeasures, modeling and analysis efforts, and similar fabrications.