Gas turbine rotor bimetallic ring seal and method therefor

摘要

A method for making a bimetallic ring seal having a nickel core covered by a first layer of platinum having a inner dense portion and a second outer portion both of which plastically deform in the presence of a load. The method includes the step of applying a porous layer of platinum over the dense layer by electroless plating in a platinum bath comprising 0.8-1.2 gram/liter platinum as diammine dinitrite salt Pt(NH3)2(NO2)2, 50-100 milliliter/liter of 25% ammonium hydroxide NH4OH; and 0.3-1.5 gram/liter hydrazine hydrate N2H4-H2O, at a temperature in the range of 75-90° C. and at a plating rate in the range of 0.5-3.0 micron/hour and then plastically deforming the ring seal under load.