Shock Wave Thermomechanical Processing of Gas Turbine Disks.
Abstract
This program involved a study of the effects of two shock wave thermomechanical processing (TMP) schedules on the microstructure, hardness, elevated temperature low-cycle fatigue, stress-rupture, and tensile properties of IN-100 (MOD) gas turbine disk alloy. Peak shocking pressures of 10,000 MPa (1450 ksi/100 kbar) for TMP Schedule I and 15,000 MPa (2175 ksi/150 kbar) for TMP Schedule II were established on subscale sonic-shaped turbine disks. These pressures were applied to flat plates of the respective schedules for mechanical property evaluations. In general, processing according to TMP Schedules I and II contributed only minor strength improvements, with a corresponding loss in ductility. Strength increases were attributed to the complex dislocation substructure created by the shock wave treatments. No significant improvement in low-cycle fatigue life was noted for either shock schedule. Stress-rupture testing showed no improvement over conventionally processed IN-100 for either schedule, and results indicated an increase in the notch sensitivity of IN-100 due to shocking. Microstructures appeared unaffected by processing schedule in optical microscopy examinations. Transmission electron microscopy studies revealed a higher dislocation density in disks shocked according to Schedule II than Schedule I. The shocking stage in both schedules prevented ripening of primary cooling conductivity on subsequent postshock heat treatments. Postshock heat treatments promoted dislocation recovery, although no real cellular substructure was observed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1980
- Accession Number
- ADA102082
Entities
People
- J. M. Robertson
- J. W. Simon
- T. D. Tillman
Organizations
- Pratt & Whitney