[en] Additions of controlled residual elements (CRE) such as titanium, boron and phosphorus, to the commercial 308 type stainless steel welds have been found to improve the creep-rupture properties. In both conventional and CRE-type stainless steel welds, during high temperature service, various microstructural changes take place such as the formation of M₂₃C₆ carbide networks along austenite(γ)-ferrite (δ) interface, the formation of sigma (σ) phase, and the dissolution of ferrite. Boron-containing CRE welds exhibit similar microstructural evolution as that of conventional types 308 stainless steel welds. As boron may segregate to ferrite-austenite interface and thereby modify the austenite-M₂₃C₆ carbide interface, the distribution of boron was measured with an atom probe field ion microscope. Atom probe analysis revealed significant boron and carbon enrichments along the ferrite-austenite boundary in the as-welded state. The ratio of carbon to boron concentration at the interface was found to be ∼ 4