Title: FORMING PROPERTIES OF STRETCH BROKEN CARBON FIBER PREPREG
Authors: Dalton B. Nold, Dilpreet S. Bajwa, Douglas Cairns, Roberta Amendola, Cecily Ryan, Chris Ridgard, Mathew Egloff
Abstract: Continuous carbon fiber is known to be a superior material for its strength, stiffness, and high strength-to-weight ratio. A challenge, however, is that it’s not versatile in forming deep drawn geometries, which require convoluted manufacturing techniques resulting in expensive components. To overcome this, a type of carbon fiber with a random discontinuous fiber alignment called stretch broken carbon fiber (SBCF) is proposed. SBCF has potential to form parts with complex geometries with comparable or better mechanical properties (e.g. strengths and stiffness) to that of continuous carbon fiber. Montana State University developed its own version of SBCF manufacturing process, and research is being conducted to understand how SBCF prepreg tows react to stretch drawing at elevated temperatures using Solvay CYCOM® 977-3 and Hexcel 8552 epoxy resin systems. Using a novel forming fixture, it has been determined that temperature, loading rate, gap width, and forming tool size are all factors contributing to the forming process. This research revealed that, for both resin systems, the forming load increases with more tool-ply contact area at room and elevated temperatures. A forming gap distance and plunger diameter were variables that were investigated to understand peak forming load trends for both elevated and room temperatures.
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Conference: SAMPE 2023
Publication Date: 2023/04/17
Price: $32.00Get This Paper