Evaluation of 2 1/4 Cr-1 Mo steel for liquid lithium containment. II. Effects of post-weld heat treatment and niobium content. Annual report, 1979

Technical Report · Mon Jan 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/6695155· OSTI ID:6695155

Anderson, T L; Edwards, G R

The lithium corrosion resistance of the regular grade of 2 1/4 Cr-1 Mo steel can be vastly improved with a proper postweld heat treatment, but even greater improvements are needed. Results indicate that if weldments were tempered sufficiently long at 760C to remove all Mo/sub 2/C from the microstructure, even greater resistance to attack by low nitrogen lithium could be achieved. Corrosion tests should eventually be performed on regular grade 2 1/4 Cr-1 Mo steel weldments which have been given a long-term (> 25 h) post-weld temper at 760C. Lithium corrosion resistance of regular grade 2 1/4 Cr-1 Mo steel may also be improved by employing a quench and temper heat treatment. Quenched microstructures have more homogenous distribution of carbides than isothermally annealed microstructures, and if properly tempered, should provide excellent lithium corrosion resistance. Furthermore, the toughness of such a lower bainite microstructure should be better than that of the ferrite-bainitic microstructure created by an isothermal anneal. Numerous parameters, all potentially deleterious to the lithium corrosion resistance of 2 1/4 Cr-1 Mo steel, remain to be investigated; two such variables are velocity effects and lead content in the lithium.

• Research Organization: Colorado School of Mines, Golden (USA). Dept. of Metallurgial Engineering
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6695155
• Report Number(s): UCRL-15313
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALKALI METALS
ALLOYS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-MOLYBDENUM STEELS
CORROSION RESISTANCE
CORROSIVE EFFECTS
CRYSTAL STRUCTURE
ELEMENTS
FLUIDS
FRACTURE PROPERTIES
HEAT TREATMENTS
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
LIQUID METALS
LIQUIDS
LITHIUM
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
QUENCHING
STEELS
TEMPERING
WELDED JOINTS