Temperature range, INOR

Plasticity. A series of relaxation tests of INOR-8 at 1200 and 1300°F has indicated that creep will be an important design consideration for reactors operating in this temperature range. The rate at which the stress must be relaxed in order to maintain a constant elastic strain at 1300°F is shown in Fig. 1.3-14, and similar data for 1200°1 are presented in Fig. 13-15. The time lapse before the material becomes plastic is about 1 hr at 1300°F and about 10 hr at 1200°F. The time period during which the material behaves elastically becomes much longer at lower temperatures, and below some temperature, as yet undetermined, the metal will continue to behave elastically indefinitely. 

Coefficient of Linear Expansion of INOR-8 FOR Several Temperature Ranges... 

The compatibility of INOR-8 and sodium is adequate in the temperature range presently contemplated for molten-salt reactor heat-exchanger operation. At higher temperatures, mass transfer could become a problem, and therefore the fabrication of duplex tubing has been investigated. Satisfactory duplex tubing has been made that consists of Inconel clad with type-316 stainless steel, and components for a duplex heat exchanger have been fabricated, as shown in Fig. 13-20. 

To determine whether interdiffusion of the alloys would result in a continuous brittle layer at the interface, tests were made in the temperature range 1300 to 1800°F. As expected, a new phase appeared at the interface between INOR-8 and the stainless steel which increased in depth along the grain boundaries with increases in the temperature. The interface of a duplex sheet held at 1300°F for 500 hr is shown in Fig. 13-22. Tests of this sheet showed an ultimate tensile strength of 94,400 psi, a 0.2% offset yield strength of 36,800 psi, and an elongation of 51%. Creep tests of the... 

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