Technical Paper

Production of cast TiAl- exhaust valves for passenger cars

International Symposium on Niobium for High Temperature Application

Nearly two years ago a production scaled prototype furnace for TiAl- automobile- valves has been put into operation by ALD at ACCESS in Aachen Germany. The project was supported by the German federal ministry for education and research. Today more than 12,000 valve planks each were cast under fully automatic process control. The manufacturing process in the prototype plant allows the production of 50 parts per pouring. An automated 2 shift operation under production cycle times was carried out in autumn this year. First results will be explained. A key for future cost reduction is the recycling of revert TiAl material. The recycling possibilities will be discussed. Also the quality assessment data will be shown in the paper to be presented. These data will include LCF testing at working temperature, X-ray inspection results, fracture toughness, metallographical inspection, chemical composition and final application in the engine. The whole ongoing work is focused to demonstrate the price targets of the automobile industry. (AU)
Technical Paper (PDF 1.34 MB)