Self-Welding Evaluation of Type 304 and A286 Stainless Steel in the Temperature Range 800 exp 0 -1140 exp 0 F in Flowing Sodium

摘要

This paper covers two material combinations, Type 304 SS vs Type 304 SS and Type 304 SS vs A286, tested at temperatures from 800 to 1140 exp 0 F for time periods up to six months in flowing sodium. Contact stresses ranged from 2 to 30 ksi on contact areas for 0.63 to 1.00 in. exp 2 . Tests were performed in either tensile or shear modes on the flat-on-flat samples. Surface morphologies of the sample before and after the test were presented. Self-welding of Type 304 SS was significant at temperatures above 1080 exp 0 F while no self-welding was detected at 800 exp 0 F. Sliding friction coefficient ( mu ) data for a Type 304 SS couple at 800 exp 0 F under compressive stresses from 2000 to 30,000 psi in sodium could be correlated quite accurately by W/sigma = 0.08e/sup 9 mu /, where W is the waviness height in microinches and sigma is the compressive stress in kilo-pound per square inch. One self-weld couple of Type 304 SS/Type 304 SS exposed at 1080 exp 0 F for 3 months was not separated but rather removed intact from the test apparatus and examined in cross-section. Scanning electron micrographs of the contacted area revealed that portions of the original interface were no longer discernible. (ERA citation 02:001036)