Method and apparatus for reducing stress on the tips of turbine or compressor blades

摘要

A method and apparatus for increasing blade fatigue strength in a turbine engine. The blades in the turbine engine are configured so as to reduce stress at the tip of the blades during operation of the turbine engine, thus increasing blade fatigue strength. This stress reduction helps to counteract the detrimental effect of abrasive tip coatings on blade fatigue strength. In one embodiment, the tip of the blade is chamfered in order to reduce the stress on the tip of the blade. An abrasive coating is then applied to the tip of the blade to assist the blade in seating into an abradable outer air seal. In another embodiment, an abrasive coating is applied to a center portion of the tip of the blade, with the periphery of the abrasive coating being set back from the opposing surfaces of the blade.