Effect of silicon on the solidification cracking behavior and metastable carbide formation in austenitic high Mn steel welds

• An addition of Si into Fe–18Mn–0.6C steel increased the solidification cracking susceptibility.
• The Si suppressed the formation of (Fe,Mn)3C eutectic carbide.
• The segregation of Si enhanced the formation of metastable (Fe,Mn)5SiC and (Fe,Mn)23C6 carbides.

Addition of 1.5 wt.% Si into Fe–18Mn–0.6C steel noticeably increased the tendency of solidification cracking. Extensive segregation of Si at the dendritic and grain boundaries suppressed the formation of (Fe,Mn)3C eutectic carbide during solidification. On the other hand, Si segregation led to the formation of a metastable carbides consisting of a mixture of (Fe,Mn)5SiC and (Fe,Mn)23C6.