Composite thermo-hydroforming is an MSU patented process similar to sheet metal hydroforming. This process uses heated and pressurized fluid to form composite blanks to a punch of desired geometry. Prior to this study, a small 40 ton press served as a proof of concept by forming 4" diameter hemispheres, allowing the lab to acquire a larger 300 ton press. This study focuses on the modification and design of the 300 ton press and using it to form advanced combat helmets using the ballistic composite Spectra Shield SR-3136. Good results are achieved in the forming process showing that composite hydroforming is a viable means for manufacturing thermoplastic composite materials. The process showed good results in the ability to form these deep drawn parts by reducing wrinkling of the final product. Concurrent to these forming experiments, the forming process is numerically modeled using Abaqus/CAE. The material is modeled using a Preferred Fiber Orientation model developed by a past student of the hydroforming lab. The model is adapted to work with a thick composite laminate consisting of many layers. Model parameters are also updated to work with a significantly thicker laminate than has been used in the past. Results of the numerical modeling show good correlation with the forming experiments. The model still shows need for improvement due to the premature onset and severity of the out of plane warping observed.
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