摘要
To date, fusion welding the precipitation-hardened austenitic Fe–Mn–Al–C lightweight alloys still remains an insurmountable challenge. In the present study, the viability of using a Fe-28.3Mn-10.2Al-1.62C (in wt.% hereafter) as a welding filler wire for gas tungsten arc welding (GTAW) of as-hot-rolled Fe-29.2Mn-8.8Al-1.65C base material (BM) were systematically investigated. It was striking that in the as-welded condition, a high density of nano-sized κ-carbide precipitates was formed by spinodal decomposition within the significantly refined austenite dendrite cells in the fusion zone (FZ). This unique feature is critical to achieve a high weld strength in virtually all fusion welded precipitation-hardened alloys. In the heat-affected zone (HAZ), the strengthening nano-sized κ-carbides originally existed in the BM was also preserved with no sign of dissolution or noticeable coarsening. Consequently, the as-welded joint exhibited a fairly uniform microhardness across the FZ, HAZ and BM. More significantly, the entire as-welded joint is free of any solidification cracking and/or liquation cracking. The as-welded joint also exhibited an excellent combination of yield strength, ultimate tensile strength and ductility.
原文 | English |
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頁(從 - 到) | 269-276 |
頁數 | 8 |
期刊 | Journal of Materials Research and Technology |
卷 | 14 |
DOIs | |
出版狀態 | Published - 1 9月 2021 |