NeT Project Task Group 8 – An International Benchmark on Residual Stress Assessment for Welding Repair

The mission of the European Network on Neutron Techniques Standardization for Structural Integrity (NeT) is to develop experimental and numerical techniques and standards for the reliable characterisation of residual stresses in structural welds. NeT was first established in 2002, and involves over 30 organisations from Europe and beyond. It operates on a “contribution in kind” basis from industrial, academic, and research facility partners. Each problem examined by the network is tackled by creating a dedicated Task Group (TG), which undertakes measurement and modelling studies and the interpretation of the results. NeT achieves this by conducting parallel measurement and prediction round robins on closely controlled and well characterized benchmark weldments. NeT TG8 follows on from the successful NeT TG1 and NeT TG4 benchmarks, which both examined welds in AISI 316L material and also NeT TG6 which examines an Alloy 600 plate containing a three pass “slot” weld made with Alloy 82 consumables. A new benchmark, NeT TG8, which examines an 18MnD5 (French nuclear code grade also named 18 MnNiMo 05) plate containing a five pass “slot” weld made with Alloy 52 consumables, has been organized to address welding repair issues. This paper describes the NeT TG8 benchmark as a whole, and presents preliminary materials characterization, residual stress measurement, and residual stress modelling results.