The Effect of Dilution on Microsegregation in AWS ER NiCrMo-14 Alloy Welding Claddings

Dilution and microsegregation are phenomena inherent to claddings, which, in turn, directly affect their main properties. This study evaluated microsegregation in the fusion zone with different dilution levels. The overlays were welded by the TIG cold wire feed process. Dilution was calculated from the geometric characteristics of the claddings and from the conservation of mass equation using chemical composition measurements. Microsegregation was calculated using energy dispersive X-ray spectroscopy measurements of the dendrites and the chemical composition of the fusion zone. The dilution of the claddings was increased by reducing the wire feed rate. Fe showed potential to be incorporated into the solid phase (k > 1), and this increased with the increase of dilution. Mo, in turn, was segregated into the liquid phase (k < 1) and also increased with the increase of dilution. However, Cr and W showed a slight decrease in their partition coefficients (k) with the increase of dilution.