Weldability studies on borated stainless steel using Varestraint and Gleeble tests

摘要

Borated austenitic stainless steels are widely used in nuclear applications due to their higher neutron absorption efficiency. Weldability of these steels is a major concern due to the formation of low-melting eutectics enriched in iron, chromium, molybdenum and boron. Varestraint and Gleeble-based tests have been carried out to evaluate the solidification and liquation cracking behaviour of 304B4 Grade B stainless steel. The solidus and liquidus temperatures have been determined using differential scanning calorimetry and Scheil simulation for solidification of welds. The results indicate that this steel has good solidification cracking resistance due to the backfilling effects of eutectic borides. However, liquation cracking resistance in this steel is moderate due to its wide nil ductility range. This paper discusses the role of boron on hot cracking susceptibility of this borated austenitic stainless steel using both the Varestraint and Gleeble-based hot ductility tests.