Method for manufacturing a poppet valve from a gamma -TiAl base alloy

摘要

A method for the manufacture of a poppet valve made of a gamma -TiAl base alloy for internal combustion engines. In this method, the gamma -TiAl blank is first subjected to primary forming, for example, by extrusion, in such a manner that thereafter it has approximately the diameter of a valve head and the material properties required for the valve head. The secondary forming is then carried out by extrusion using a die designed in such a manner that the diameter of the inlet opening corresponds approximately to that of the blank after primary forming, and a cylindrical section corresponding to this diameter, followed by a transition in the form of a narrowing which corresponds approximately to the valve cone to the outlet opening. The outlet opening has at least approximately the same diameter as the diameter of the valve shaft. The extrusion process is terminated when the desired thickness of the valve head has been attained.