POPPET VALVE SUBJECTED TO SOLUTION HEAT-TREATMENT AND ITS PRODUCTION

摘要

An engine poppet valve is manufactured to have a microstructure that varies by location to match the stresses, temperature, wear and other conditions encountered in service. The microstructure is characterized by a coarse grain size in the head adjacent its combustion face, a fine grain size in the head adjacent its seat face, and a fine grain size in the stem.