The results of an experimental investigation of rim cracking in a welded-blade composite gas-turbine wheel, in two carbon-steel disks, and in five tool-steel disks are presented.nIn order to determine the effectiveness of holes in preventing crack propagation, l/8-inch and l/l6-inch-diameter holes were drilled in the rim of the welded-blade composite gas-turbine wheel. Although causing the cracks to grow through the holes in the course of sub¬jecting the wheel to thermal-stress cycles was impossible, the effectiveness of the holes in preventing crack growth was difficult to estimate accurately. The estimation was difficult because a considerable portion of the stress relief appeared to be occurring in a few long cracks, which existed before the holes were drilled in the rim. Crack growth occurred during the cooling part of the thermal-stress cycle.
展开▼
