ISSN: 1945-7553
CODEN: JTEVAB
Page Count: 6

Estimation of Fatigue Life at Elevated Temperature of Electron Beam Weldments of Alloy 718

Fukakura, J
Heavy Apparatus Engineering Laboratory, Toshiba Corporation, Yokohama,

Mori, T
Heavy Apparatus Engineering Laboratory, Toshiba Corporation, Yokohama,

Abstract

Axial displacement-controlled fatigue tests were conducted at 600°C on smooth solid cylindrical specimens of Alloy 718 with electron beam weldments. By monitoring the diametral strain response of the heat-softened region, relationships between strain amplitude and fatigue life, and between cyclic stress and strain, were obtained. Using the cyclic stress-strain curve of the soft region, the load-controlled fatigue test results corresponded to the axial displacement-controlled test results. Subsequently, a simple model of strain sharing in the weldment was established for cyclic loading in order to estimate the fatigue life. Using the model, the fatigue life of a welded specimen under axial loading was estimated as a function of gage length, considering the effect of gage length on strain concentration in the soft region.

Keywords:
fatigue, elevated temperature, Alloy 718, electron beam welding

Paper ID: JTE10313J
DOI: 10.1520/JTE10313J
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