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Sham, Sam

Publications and source records attributed to Sham, Sam.

High Temperature Materials

Overview of high temperature metals, including component construction rules for advanced reactor designs, assessment of filler metal for Alloy 800H weldments, high-temperature crack growth rate testing, work packages and contributors for FY24, creep-fatigue damage summation evaluation, GCR metal needs, and high temperature metals from other programs.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Report on FY 2020 creep, fatigue and creep fatigue testing of Alloy 709 base metal at ORNL

The testing activities and research in support of ASME Code qualification of Alloy 709, an advanced austenitic steel, are being carried out at Oak Ridge National Laboratory (ORNL), Argonne National Laboratory, and Idaho National Laboratory. This report summarizes the status and results of FY 2020 planned testing at ORNL. Uniaxial tensile tests on the electroslag remelt (ESR) solution-annealed plate (heat number 58776-3RBC) with additional heat treatment were performed for the baseline mechanical properties evaluation for ASME code qualification of Alloy 709. The tensile properties were found to meet ASME SA-213 specifications and were comparable to the Nippon Steel NF709 data generated for an ASME Section I Code Case for seamless tubing. ORNL was tasked to carry out a subset of the Code Case testing for creep rupture. Creep rupture data from 18 tests were generated on a solution-annealed ESR plate with a solution annealing temperature of 1100°C. There are total of 19 intermediate and long-term creep rupture tests of Alloy 709 ongoing at ORNL. A preliminary fatigue design curve at 760°C was developed for Alloy 709, and the results show that the fatigue design curve of Alloy 709 is comparable to that of Alloy 800H at 760°C.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Advanced Materials Program Summary

Materials solutions - enabling design, construction, and operation of licensable Advanced Nuclear Material, design, fabrication, installation, examination, testing, overpressure protection, inspection, stamping, and certification

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Report on FY 2020 Testing in Support of the Development and Extension of ASME Code Rules for Grade 91

This report summarizes the FY 2020 research and activities at Oak Ridge National Laboratory in support of the ASME code rule development and code extension for Grade 91 (Gr. 91) steel. Incorporation of the Gr. 91 temperature-dependent fatigue curves in Section III Division 5 was one major task, and the associated major aspects brought up during the course of the ASME balloting process are documented in this report. Experiments and analysis continued on the development of the alternative creep-fatigue evaluation based on elastic–perfectly plastic (EPP) plus simplified model test (SMT) methodology. The focus of the study in FY 2020 was the evaluation of the hold-time effect at high cycle and low strain range region. Baseline testing in support of the evaluation of hold time effects was started and will continue in FY 2021. Major on-going experiments and activities in support of the ASME code development and extension of Gr. 91 will be completed in FY 2021.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Technical Gap Assessment for Materials and Component Integrity Issues for Molten Salt Reactors

Material selection and qualification is an important consideration for the deployment of molten salt reactors (MSRs). This report summarizes the most important materials issues that must be considered for licensing MSRs. Because of the variety of MSR designs under consideration, this report considers materials for both fluoride and chloride applications, with both fast and thermal neutron spectra.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

FY17 Status Report on Testing Supporting the Inclusion of Grade 91 Steel as an Acceptable Material for Application of the EPP Methodology

This report summarizes the experiments performed in FY17 on Gr. 91 steels. The testing of Gr. 91 has technical significance because, currently, it is the only approved material for Class A construction that is strongly cyclic softening. Specific FY17 testing includes the following activities for Gr. 91 steel. First, two types of key feature testing have been initiated, including two-bar thermal ratcheting and Simplified Model Testing (SMT). The goal is to qualify the Elastic – Perfectly Plastic (EPP) design methodologies and to support incorporation of these rules for Gr. 91 into the ASME Division 5 Code. The preliminary SMT test results show that Gr. 91 is most damaging when tested with compression hold mode under the SMT creep fatigue testing condition. Two-bar thermal ratcheting test results at a temperature range between 350 to 650o C were compared with the EPP strain limits code case evaluation, and the results show that the EPP strain limits code case is conservative. The material information obtained from these key feature tests can also be used to verify its material model. Second, to provide experimental data in support of the viscoplastic material model development at Argonne National Laboratory, selective tests were performed to evaluate the effect of cyclic softening on strain rate sensitivity and creep rates. The results show the prior cyclic loading history decreases the strain rate sensitivity and increases creep rates. In addition, isothermal cyclic stress-strain curves were generated at six different temperatures, and a nonisothermal thermomechanical testing was also performed to provide data to calibrate the viscoplastic material model.

36 MATERIALS SCIENCE↗