Formation of Microchannels in Sintered Titanium-Powder Compacts by Microscopic Reactive Infiltration
Tatsuya Ohmi, Masayuki Sakurai, Kiyotaka Matsuura, Masayuki Kudoh and Manabu Iguchi
A simple and economical method for fabricating microchannels in titanium alloy bodies has been investigated experimentally. A titanium-powder compact containing shaped aluminum wires was sintered at a temperature above the melting point of aluminum. Microscopic reactive infiltration of molten aluminum into the surrounding titanium powder, accompanied by the reaction between Al and Ti, occurred during the sintering and brought about the formation of microchannels lined with Ti-Al alloy layers in the sintered body. The Ti-Al alloy liner was composed of titanium aluminides when the sintering time was relatively short. In contrast, the primary phase of the liner changed from titanium aluminides to titanium solid solutions when the sintering time was longer because of the progression of aluminum diffusion.