A new method for the rapid processing of thin-gage sheet of traditionally difficult-to-process materials has been developed. The method uses high-density infrared (HDI) rapid heating of a plasma-arc lamp to liquid-phase sinter powder metal compact precursors to a dense structure. Using this method, intermetallic sheet can be produced in a fraction of the time at a significant cost savings over traditional processing methods. In this work, gamma titanium aluminides (gamma-TiAl) sheet was produced using HDI from powder precursors.; A mathematical model was developed in order to determine lamp processing parameters. The model was developed using nickel materials and uses a comprehensive set of thermophysical data to predict temperature fields and phase changes during processing. The model was extended to the gamma-TiAl material system. With the aid of the model, processing parameters were determined that allowed for a temperature gradient across the sheet that would produce a liquid-phase cast structure on the surface, residual powder on the backside, and a middle layer solid + liquid zone. The later region produced an optimal fine-grain, lamellar microstructure that yields the best mechanical properties. The model also reduced costs by removing the need for front-end experiments.; Postprocessing investigations showed that HDI was an effective tool for producing sheet. Measurements of density and mechanical properties revealed that HDI-produced gamma-TiAl was >99% dense and had a tensile strength of 428 MPa and ductility of 0.55%. Light microscope investigation showed the predicted fine-grain, lamellar microstructure was achieved. Results of HDI processing were compared to material processed by traditional methods.
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