Life Prediction and Constitutive Models for Engine Hot Section Anisotropic Materials Program

By National Aeronautics and Space Administration

This report presents the results from a 35 month period of a program designed to develop generic constitutive and life prediction approaches and models for nickel-based single crystal gas turbine airfoils. The program is composed of a base program and an optional program. The base program addresses the high temperature coated single crystal regime above the airfoil root platform. The optional program investigates the low temperature uncoated single crystal regime below the airfoil root platform including the notched conditions of the airfoil attachment. Both base and option programs involve experimental and analytical efforts. Results from uniaxial constitutive and fatigue life experiments of coated and uncoated PWA 1480 single crystal material form the basis for the analytical modeling effort. Four single crystal primary orientations were used in the experiments: (001), (011), (111), and (213). Specific secondary orientations were also selected for the notched experiments in the optional program. Constitutive models for an overlay coating and PWA 1480 single crystal material were developed based on isothermal hysteresis loop data and verified using thermomechanical (TMF) hysteresis loop data. A fatigue life approach and life models were selected for TMF crack initiation of coated PWA 1480. An initial life model used to correlate smooth and notched fatigue data obtained in the option program shows promise. Computer software incorporating the overlay coating and PWA 1480 constitutive models was developed. Nissley, D. M. and Meyer, T. G. ENGINE PARTS; FATIGUE LIFE; GAS TURBINE ENGINES; LIFE (DURABILITY); MATHEMATICAL MODELS; PREDICTION ANALYSIS TECHNIQUES; PROTECTIVE COATINGS; ANISOTROPY; COMPUTER PROGRAMS; CRACK INITIATION; HIGH TEMPERATURE TESTS; HYSTERESIS; SINGLE CRYSTALS...

• Format: Paperback
• Language: English
• ISBN: 1731541899
• ISBN13: 9781731541895
• Release Date: January 1
• Publisher: Independently Published
• Length: 178 Pages
• Weight: 0.94 lbs.
• Dimensions: 0.4" x 8.5" x 11.0"