Details

Autor(en) / Beteiligte

• Sam, Shiju
• Das, C.R.
• Ramasubbu, V.
• Albert, S.K.
• Bhaduri, A.K.
• Jayakumar, T.
• Rajendra Kumar, E.

Titel

Delta ferrite in the weld metal of reduced activation ferritic martensitic steel

Ist Teil von

• Journal of nuclear materials, 2014-12, Vol.455 (1-3), p.343-348

Erscheinungsjahr

2014

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• Formation of delta( delta )-ferrite in the weld metal, during autogenous bead-on-plate welding of Reduced Activation Ferritic Martensitic (RAFM) steel using Gas Tungsten Arc Welding (GTAW) process, has been studied. Composition of the alloy is such that delta-ferrite is not expected in the alloy; but examination of the weld metal revealed presence of delta-ferrite in the weld metal. Volume fraction of delta-ferrite is found to be higher in the weld interface than in the rest of the fusion zone. Decrease in the volume fraction of delta-ferrite, with an increase in preheat temperature or with an increase in heat input, is observed. Results indicate that the cooling rate experienced during welding affects the volume fraction of delta-ferrite retained in the weld metal and variation in the delta-ferrite content with cooling rate is explained with variation in the time that the weld metal spends in various temperature regimes in which delta-ferrite is stable for the alloy during its cooling from the liquid metal to the ambient temperature. This manuscript will discuss the effect of welding parameters on formation of delta-ferrite and its retention in the weld metal of RAFM steel.