Is this the loading temperature or is this a heat that will be introduced and removed frequently? There may be several ways this effects the material. Perhaps explain in what manner this is taking place or apllicable.
The yield strength of 316 at 650 degrees f is 21 ksi. This information
comes from 9.49 of High-Temperature Property Data: Ferrous Alloys
published by ASM International ISBN: 0-87170-243-6
The allowable tensile strength (to be used in design equations) for plate material SA240-316 (UNS No. : S31600) is : @ ambient temp.: 20 000 psi and @ 650 oF 16 600 psi.
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