Microstructural Study of Failure Mechanisms during Mechanical Testing in Coal Gasification Environments

摘要

This report sets forth the results of a microstructural study of the behavior of iron-chrome-nickel alloys under the combined effects of stress and corrosive species encountered in coal gasification. The work involved systematic study of the effects of variations in alloy and environment compositions. Included are oxidizing and sulfidizing gas compositions. Model alloys were procured and heat treated. In addition, microstructural changes which occur in 310 stainless steel, Incoloy 800H, RA 333 and IN 657 during stress rupture testing in a simulated coal gasification environment at 1500 F were examined. Optical metallography and energy dispersive X-ray analysis were used to characterize the microstructure and mechanisms were proposed.