Patent ID: 8382441
Filing Date: 2013-02-26
Classification: B21D,B23K,F01D,F05D,Y02T

Abstract:
1. A method of manufacturing a blade for a turbomachine by superplastic forming and diffusion bonding a first layer, a second layer and a membrane, the membrane being disposed between the first and second layers, the method comprising: applying a stop-off material in a first predetermined pattern between the first layer and the membrane so as to prevent a diffusion bond from forming between the first layer and the membrane across said first predetermined pattern; wherein the first pattern is applied such that it defines one or more first strips and one or more first dots, the first strips and first dots being void of the stop-off material, and wherein the first strips are arranged in a span-wise direction, and the first dots are located between the first strips and the blade tip edge, the first dots being offset from a longitudinal axis of the first strips in a chord-wise direction; and applying the stop-off material in a second predetermined pattern between the second layer and the membrane so as to prevent a diffusion bond from forming between the second layer and the membrane across said second predetermined pattern; wherein the second pattern is applied such that it defines one or more second strips and one or more second dots, the second strips and second dots being void of the stop-off material, and wherein the second strips are arranged in a span-wise direction and the second dots are located between the second strips and the blade tip edge, the second dots being offset from a longitudinal axis of the second strips in a chord-wise direction; wherein the first and second predetermined patterns are applied such that the second strips are spaced apart from the first strips and the first dots are spaced apart from the second dots on opposite sides of the membrane.