Isothermal calorimetric observations of the effect of welding on compatibility of stainless steels with high-test hydrogen peroxide propellant

Welding of stainless steels (CRES 316L and CRES 304L) was found to increase surface roughness and more importantly to decrease their compatibility with high-test hydrogen peroxide (HTP). Compatibility was determined by isothermal microcalorimeter (IMC) measurements. Omission of a purge gas enhances welding effects. Previous literature indicated welding causes segregation of chromium and iron in the heat affected zone (HAZ) and in the weld bead itself. It is likely that these surface modifications are responsible for the diminished compatibility, however a direct correlation was not established.