Method of treating a valve comprising a nitruration step and valve obtained by this method

摘要

The method involves forming a peripheral layer of nitride material. Surface state of a valve (14) is improved at level of its range against a seat (24) of the valve by preserving the nitride material layer of sufficient thickness to resist temperatures of combustion of an engine. The thickness of the layer at the level of range is higher or equal to five micrometers. An independent claim is also included for a valve of an internal combustion engine.