Ceramic valve for reciprocating piston engines consists of ceramic valve plate and ceramic valve shaft of silicon nitride, connected via a hard-solder connection with silicon

摘要

The valve has a ceramic valve plate (4) and a ceramic valve shaft (3), with a rotary symmetrical joint face projecting axially into the valve plate interior. The connection between the valve parts, which are formed by separate blanks, is a hard-solder connection, with a hard-solder of e.g. metal or metal-like material, which when melting undergoes an irreversible chemical connection with the ceramic material. Both valve plate and shaft are of the same silicon nitride, and the hard solder is a silicon or silicon-iron alloy, of a composition dependent upon thermal loads on the valve.