ASSET Technology Update for Analyzing and Predicting Corrosion in High Temperature Gases

摘要

This presentation updates a long-standing effort to develop an information system for corrosion of metals and alloys in high temperature gases. The current database represents 13.7 million hours of exposure time for 8,500 tests with 87 commercial alloys. The data cover temperatures of 100-1200°C and exposure times of up to 20,000 hours. The system utilizes corrosion data from well-defined exposures, determines corrosion product stabilities and assesses corrosion losses for wide ranges of exposure conditions. Development of this program has developed new insights via analysis of thermochemical data for alloys rich in Fe-Ni-Cr-Co and exposed to gases containing C-O-S-N-Cl-H. All known thermochemical data for the potential corrosion product phases based upon potential reactions between these alloys and gases were compiled and allow complete assessments of corrosion product stabilities, which are used to infer the dominant corrosion mechanism. The technology is used in corrosion research, alloy development, failure analysis, lifetime prediction, and process operations. The corrosion mechanisms emphasized are oxidation, sulfidation, sulfidation/oxidation, and carburization, corrosion by HC1, corrosion by Cl{sub}2 and nitridation. Engineering lifetimes of alloys and the effects of complex exposure conditions can be estimated by the technology.