IIW Recommendations on HFMI Treatment

This second edition presents a substantially expanded and refined set of IIW Recommendations, delivering updated and clarified design rules supported by extensive new data for engineers working with HFMItreated welded joints. It introduces relaxed weldgeometry requirements prior to treatment, revised thicknesscorrection factors consistent with the 2024 IIW Fatigue Design Guidelines, and greatly enlarged tables covering fatigue strength across material grades, load ratios, stress ranges, and assessment methods. The scope has been broadened to include steels with yield strengths up to 1300MPa, alongside refined limits for variableamplitude loading. New chapters provide guidance on retrofitting and lifeextension of existing structures, as well as methodologies for assessing HFMI devices based on experimental evidence. With clearer procedures, expanded applicability, and rigorously updated technical content, this edition serves as a comprehensive, practiceoriented reference for the design, verification, and upgrading of welded structures using HFMI treatment.

Gary B. Marquis is a professor of applied mechanics at Aalto University, Finland. Within IIW, he served as a chair for Commission XIII: Fatigue of welded components and structures for eight years, chair of the IIW Technical Management Board and as IIW president for three years. Zuheir Barsoum is a professor of lightweight structures at KTH Royal Institute of Technology, Stockholm, Sweden. Within IIW, he has served as chairman for XIII-WG2: Techniques for improving the fatigue strength of welded joints for 8 years, vice chairman for Commission XIII for 6 years and member of IIW TMB (Technical Management Board) for 3 years. Martin Leitner is a professor of structural durability and railway technology at Graz University of Technology, Austria. Within IIW, he is currently chair of Sub-Commission XIII-SC-B: Fatigue Improvement Techniques.