Weldability and Mechanical Properties of Age-Hardened Fe-Ni-Cr-Mn-Ti Austenitic Alloy for Cryogenic Use
The electron beam weldability and the low temperature mechanical and magnetic properties of Mn-modified iron-base superalloys have been investigated. Mn addition to an Fe-30Ni-13Cr-2.4Ti alloy suppressed the occurrence of ferromagnetism at 4.2K and did not cause any deleterious effects on the mechanical properties of the alloy and its weldability, i.e., the alloys containing from 3 to 9 mass% Mn were welded without any fusion zone hot cracking and HAZ micro-fissuring. The post-weld heat-treatment which consists of solutionizing followed by aging was very effective to diminish the strength mismatch between base metal and weld metal regions. The absorbed energy of impact specimens of weldments for both the as-welded and heat-treated conditions showed higher values than those of the base materials.
KeywordsFusion Zone Magnetization Curve Electron Beam Weldability Austenitic Alloy Soft Zone
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