Influence of C, Mn and Ni Contents on Microstructure and Properties of Strong Steel Weld Metals — Part I. Effect of Nickel Content
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چکیده
The effects of increasing nickel from 3 to 7 and 9 wt. % were investigated in high strength steel weld metals with 2 wt. % manganese. It was found that nickel additions were positive for strength but negative for impact toughness. Significant segregation of nickel and manganese to interdendritic regions was observed with the two higher nickel contents. In these weld metals a mainly martensitic microstructure developed at interdendritic regions while bainite was found at dendrite core regions. The microstructural inhomogeneity was due to segregation and the accompanying stabilisation of austenite in solute enriched regions to lower transformation temperatures. With 3 wt. % nickel the microstructure was found more homogenous with mainly bainite forming. The decrease in impact toughness with increasing nickel content was mainly attributed to the formation of coarse grained coalesced bainite.
منابع مشابه
Influence of C, Mn and Ni Contents on Microstructure and Properties of Strong Steel Weld Metals — Part II. Impact Toughness Gain from Manganese Reductions
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