Influence of carbon, manganese and nickel on microstructure and properties of strong steel weld metals Part 1 – Effect of nickel content
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چکیده
The effects of increasing the nickel content from 3 to 7 or 9 wt-% were investigated in high strength steel weld metals with 2 wt-% manganese. Nickel additions were beneficial to strength but detrimental to impact toughness. Significant segregation of nickel and manganese to interdendritic regions was observed at the two higher nickel contents. In these weld metals a mainly martensitic microstructure developed at interdendritic regions, whereas 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 to be more homogeneous, 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 carbon, manganese and nickel on microstructure and properties of strong steel weld metals Part 2 – Impact toughness gain resulting from manganese reductions
Two experimental high strength steel weld metals were produced with 7 wt-% nickel and either 2 or 0.5 wt-% manganese. Neural network predictions that it is advantageous to reduce the manganese concentration in high nickel alloys have been confirmed, with impact energy increasing from 32 to 113 J at –40uC. High resolution microstructural investigations showed that both weld metals contained main...
متن کاملInfluence of C, Mn and Ni Contents on Microstructure and Properties of Strong Steel Weld Metals — Part I. Effect of Nickel Content
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 ...
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