Development of ODS Heat Exchanger Tubing Progress Report (open access)

Development of ODS Heat Exchanger Tubing Progress Report

Work continued on four major tasks of this project--increasing the circumferential strength of MA956 tubing, joining of the MA956 alloy, determining the bending limits of MA956 tubing, and determination of the high temperature corrosion limits of the MA956 alloy. With respect to increasing the circumferential strength of a MA956 tube, an additional 120 MA956 rods have been extruded (total of 180 rods) using 16:1 and 10:1 extrusion ratios and extrusion temperatures of 1000, 1075, 1150, and 1200 C. Also, approximately 40 cold work (0, 10, 20, 30, 40%) plus annealing treatments (1000, 1150, 1300 C) have been completed with the resulting sample microstructures presently being analyzed. Creep testing to determine the ''stress threshold'' curves for this alloy continues. Regarding joining of the MA956 alloy, work continued using friction welding, magnetic impulse welding, explosive welding, and transient liquid phase bonding, with encouraging results obtained from the friction, explosive, and transient liquid phase joining methods. Initial work on determining the bending limits of the MA956 tubing has shown that the recrystallized material shows good ductility but the unrecrystallized material does not. And finally, fluid-side high temperature corrosion testing of the material continues and the environment for the laboratory fireside corrosion testing has …
Date: October 1, 2001
Creator: Mark A. Harper, Ph.D.
System: The UNT Digital Library
Development of ODS Heat Exchanger Tubing Progress Report (open access)

Development of ODS Heat Exchanger Tubing Progress Report

Work has begun under three major tasks of this project. With respect to increasing the circumferential strength of a MA956 tube, approximately 60 MA956 rods have been extruded using a 20:1 extrusion ratio and extrusion temperatures of 1000, 1075, 1150, and 1200 C. Also, creep testing is underway for the purpose of determining the ''stress threshold'' curves for this alloy. Regarding joining of the alloy MA956, work has begun on the friction welding, magnetic impulse welding, explosive welding, and transient liquid phase bonding aspects of this project. And finally, material is being prepared for the laboratory fire-side high temperature corrosion tests, with potential gas and deposits for a typical Vision 21 plant being reviewed for final determination of these variables in the test program.
Date: April 30, 2001
Creator: Harper, Mark A.
System: The UNT Digital Library