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Infusion Processing of Phenylethynyl Terminated Imides by High Temperature RTM and VARTMFabrication of composite structures using infusion processes such as resin transfer molding (RTM) and vacuum assisted resin transfer molding (VARTM) is generally more affordable than conventional autoclave techniques. Recent efforts have focused on adapting both technologies for the fabrication of high temperature (HT) resistant composites. Due to their low melt viscosity and long melt stability, certain phenylethynyl terminated imides (PETI) can be processed into composites using these high temperature out-of-autoclave processes. In the current study, two PETI resins, LARC(TradeMark) PETI-330 and LARC(TradeMark) PETI-8 have been used to make test specimens using both RTM and VARTM. For aerospace applications, a void fraction of less than 2% is desired. Traditionally, RTM has had the advantage over VARTM for generating composites with low void content. However, the process is limited in terms of size. Work at NASA LaRC has incorporated modifications to the thermal cycle used in laminate fabrication that have reduced the void content significantly (typically 1-3%) using the current HT-VARTM process. For composite fabrication by both RTM and VARTM, the resins were infused into three carbon fiber preforms (T650-35-3k 5HS, IM7-6k 5HS, and IM7-6k Uniweave) at 316 C and 260 C respectively and cured up to 371 C. The details of the RTM processing carried out at the University of Akron are discussed in this work along with a brief description of the HT-VARTM processing carried out at NASA-LaRC. Photomicrographs of the panels were taken and void contents were determined by acid digestion. Mechanical properties (short beam shear, SBS) of the panels fabricated by both infusion processes were determined at room temperature as well as at various elevated temperatures. The results of this work are presented herein.
Document ID
Acquisition Source
Langley Research Center
Document Type
Conference Paper
Ghose, Sayata
(National Inst. of Aerospace Hampton, VA, United States)
Lewis, Todd M.
(Akron Univ. Akron, OH, United States)
Cano, Roberto J.
(NASA Langley Research Center Hampton, VA, United States)
Watson, Kent A.
(National Inst. of Aerospace Hampton, VA, United States)
Isayev, Avraam I.
(Akron Univ. Akron, OH, United States)
Date Acquired
August 25, 2013
Publication Date
October 17, 2011
Subject Category
Composite Materials
Report/Patent Number
Meeting Information
Meeting: SAMPE 2011 Fall Technical Conference
Location: Fort Worth, TX
Country: United States
Start Date: October 17, 2011
End Date: October 20, 2011
Sponsors: Society for Advancement of Materials and Process Engineering
Funding Number(s)
WBS: WBS 984754.
Distribution Limits
Public Use Permitted.
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