Weld Cracking in Duplex Stainless Steel (Report I) : Aspects of Solidification Sequence Revealed by Quenching(Materials, Metallurgy & Weldability)
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Solidification sequence of duplex stainless steel weld metals was investigated by observing the typical solidification modes of commercial stainless steels. Freezing the solidification microstructure of each material were made with liquidtin quenching during GTA welding. It was found that liquid-tin quenching has sufficient cooling rate to reveal the dendritic substructure near the solidification front even though weld metal solidifies with primary ferrite. This dendritic substructure was gradually obscured with decreasing the temperature even within the BTR, and liquid droplet was confined at the interdendritic boundary due to the development of the solid bridge which was formed at very high temperature near the solidification front. Moreover, the secondary dendrite arm boundary was apt to be obscured compared with the primary dendrite arm boundary. The characteristic features mentioned above was remarkable in dupex and ferritic stainless steels.
- Trans. JWRI
Trans. JWRI 16, 343, 1987