ASME Section VIII Local Strain Limit Material Property Requirements and Notch Tensile Testing Method Proposal

Abstract The 2007 rewrite of ASME Section VIII, Division 2 introduced a local strain limit methodology to be applied to elastic plastic design analyses in both ASME Section VIII, Divisions 2 and 3. As new materials are introduced to the Code, this leaves a gap as to what information needs to be supplied for new materials to be able to be accepted. ASME Section II, Part D, Appendix 5 contains general guidelines for material data to be supplied for the acceptance of new materials into the Code. However, it is only for basic information required and leaves a statement that “other additional data” may be required as specified by the Code of Construction. The following paper discusses the background of the methodology currently in ASME Section VIII, Division 2 and 3. It further contains a proposed testing methodology to be followed for new materials in ASME Section VIII relative to local strain limits. The final part of the paper discusses testing experience with some material data produced following this methodology and how it was utilized to gain acceptance by the ASME Section VIII Standards committee. The intent of the paper is to serve as a basis for a new testing specification for notch tensile testing to support the inclusion of new materials into Section VIII. It will also contain a guideline on how to process the data to obtain material constants used in the local strain limit evaluation in Section VIII elastic plastic analyses.