Elevated temperature axial and torsional fatigue behavior of Haynes 188

Technical Report · Mon Jun 01 04:00:00 EDT 1992

OSTI ID:7242459

Bonacuse, P J; Kalluri, S

The results of high-temperature axial and torsional low-cycle fatigue experiments performed on Haynes 188, a wrought cobalt-base superalloy, are reported. Fatigue tests were performed at 760 C in air on thin-walled tubular specimens at various ranges under strain control. Data are also presented for coefficient of thermal expansion, elastic modulus, and shear modulus at various temperatures from room to 1000 C, and monotonic and cyclic stress-strain curves in tension and in shear at 760 C. The data set is used to evaluate several multiaxial fatigue life models (most were originally developed for room temperature multiaxial life prediction) including von Mises equivalent strain range (ASME boiler and pressure vessel code), Manson-Halford, Modified Multiaxiality Factor (proposed here), Modified Smith-Watson-Topper, and Fatemi-Socie-Kurath. At von Mises equivalent strain ranges (the torsional strain range divided by the square root of 3, taking the Poisson's ratio to be 0.5), torsionally strained specimens lasted, on average, factors of 2 to 3 times longer than axially strained specimens. The Modified Multiaxiality Factor approach shows promise as a useful method of estimating torsional fatigue life from axial fatigue data at high temperatures. Several difficulties arose with the specimen geometry and extensometry used in these experiments. Cracking at extensometer probe indentations was a problem at smaller strain ranges. Also, as the largest axial and torsional strain range fatigue tests neared completion, a small amount of specimen buckling was observed.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
• OSTI ID: 7242459
• Report Number(s): N-92-28701; NASA-TM--105396; E--6788; NAS--1.15:105396; AVSCOM-TR--91-C-045; CNN: RTOP 553-13-00
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
ALLOY-CO36CR22NI22W15FE3
ALLOYS
BOILERS
BUCKLING
CHROMIUM ALLOYS
COBALT
COBALT ALLOYS
COBALT BASE ALLOYS
CONTAINERS
CORROSION RESISTANT ALLOYS
ELEMENTS
EVALUATION
EXPANSION
EXTENSOMETERS
FATIGUE
HAYNES 188 ALLOY
HAYNES ALLOYS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
LANTHANUM ADDITIONS
LANTHANUM ALLOYS
MATERIALS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
METALS
POISSON RATIO
PRESSURE VESSELS
RARE EARTH
RARE EARTH ALLOYS
SHEAR
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
THERMAL EXPANSION
THERMAL FATIGUE
TORSION
TRANSITION ELEMENTS
YOUNG MODULUS