Creep embrittlement in aged HP-Mod alloy reformer tubes
Source abstract
Abstract
Abstract The welding of service-exposed, aged Heat Resistant Nickel-Base alloys is notorious in industry for being extremely difficult. There is an extremely high propensity for cracking in the heat affected zone of the weld joint. During a Reformer's service and/or periodic offline inspections, it may be determined that repairs are necessary and as such sections of the tube are replaced. However, attempts to weld are often hindered by the manifestation of cracks adjacent to the weld during or immediately after the welding process. In this investigation, service-exposed aged reformer tube material (HP-Mod.Nb or 25Cr/35Ni/1Nb/0.4C) sections were welded using the current procedures and parameters used in practice and the resultant effects on the microstructure and mechanical properties evaluated. Characteristic cracking typical to that observed in field welds was experienced. The observed cracks were subjected to a failure analysis to identify the responsible damage mechanism. It was found that the root cause of the cracking was due to Creep Embrittlement. Modification of the existing weld procedure can serve to reduce the effects of this damage mechanism.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Hydrogen embrittlement and corrosion behaviors in metals · Fatigue and fracture mechanics · High Temperature Alloys and Creep
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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