Post-test examination of a pool boiler receiver

Technical Report · Wed Apr 01 00:00:00 EST 1992

OSTI ID:10154179

Dreshfield, R L; Moore, T J; Bartolotta, P A

A subscale pool boiler test apparatus to evaluate boiling stability developed a leak after being operated with boiling NaK for 791.4 hr at temperatures from 700 to 750 {degrees}C. The boiler was constructed using Inconel 625 with a type 304L stainless steel wick for the boiler and type 316 stainless steel for the condenser. The boiler assembly was metallurgically evaluated to determine the cause of the leak and to assess the effects of the NaK on the materials. It was found that the leak was caused by insufficient (about 30 percent) joint penetration in a butt joint. There was no general corrosion of the construction materials, but the room temperature ductility of the Inconel 625 was only about 6.5 percent. A crack in the heat affected zone of the Inconel 625 near the Inconel 625 to type 316 stainless steel butt joint was probably caused by excessive heat input. The crack was observed to have a zone depleted of iron at the crack surface and porosity below that zone. The mechanism of the iron depletion was not conclusively determined. 3 refs.

• Research Organization: National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AT04-85AL33408
• OSTI ID: 10154179
• Report Number(s): DOE/NASA-33408-6; NASA-TM-105635; ON: DE92015983
• Resource Relation: Other Information: PBD: Apr 1992
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
SOLAR RECEIVERS
PERFORMANCE TESTING
INCONEL 625
STAINLESS STEEL-316
WELDED JOINTS
LEAKS
STAINLESS STEEL-304
LIQUID METALS
POTASSIUM BASE ALLOYS
SODIUM ALLOYS
STIRLING ENGINES
SOLAR THERMAL CONVERSION
MECHANICAL PROPERTIES
TEMPERATURE RANGE 0400-1000 K
140700
141000
360103
SOLAR THERMAL POWER SYSTEMS
SOLAR COLLECTORS AND CONCENTRATORS