Prediction of Corrosion of Advanced Materials and Fabricated Components

Anderko, A. ; Engelhardt, G. ; Inc.), M.M. Lencka (OLI Systems ; Jakab, M.A. ; Tormoen, G. ; Institute), N. Sridhar (Southwest Research

OLI Systems, Inc.

关键词: Corrosion;    Alloys;    Corrosion, Nickel-Base Alloys, Stainless Steels, Pitting, Crevice Corrosion, Prediction, Modeling, Electrochemistry, Thermodynamics, Software;    Corrosion Protection;    Crevice Corrosion;   

DOI  :  10.2172/916966
RP-ID  :  OLI-2007-09-29
RP-ID  :  FC36-04GO14043
RP-ID  :  916966

美国|英语

来源: UNT Digital Library

【 摘 要 】

The goal of this project is to provide materials engineers, chemical engineers and plant operators with a software tool that will enable them to predict localized corrosion of process equipment including fabricated components as well as base alloys. For design and revamp purposes, the software predicts the occurrence of localized corrosion as a function of environment chemistry and assists the user in selecting the optimum alloy for a given environment. For the operation of existing plants, the software enables the users to predict the remaining life of equipment and help in scheduling maintenance activities. This project combined fundamental understanding of mechanisms of corrosion with focused experimental results to predict the corrosion of advanced, base or fabricated, alloys in real-world environments encountered in the chemical industry. At the heart of this approach is the development of models that predict the fundamental parameters that control the occurrence of localized corrosion as a function of environmental conditions and alloy composition. The fundamental parameters that dictate the occurrence of localized corrosion are the corrosion and repassivation potentials. The program team, OLI Systems and Southwest Research Institute, has developed theoretical models for these parameters. These theoretical models have been applied to predict the occurrence of localized corrosion of base materials and heat-treated components in a variety of environments containing aggressive and non-aggressive species. As a result of this project, a comprehensive model has been established and extensively verified for predicting the occurrence of localized corrosion as a function of environment chemistry and temperature by calculating the corrosion and repassivation potentials.To support and calibrate the model, an experimental database has been developed to elucidate (1) the effects of various inhibiting species as well as aggressive species on localized corrosion of nickel-base alloys, stainless steels and copper-nickel alloys and (2) the effects of heat treatment on localized corrosion. Excellent agreement with experimental data has been obtained for alloys in various environments, including acids, bases, oxidizing species, inorganic inhibitors, etc. Further, a probabilistic model has been established for predicting the long-term damage due to localized corrosion on the basis of short-term inspection results. This methodology is applicable to pitting, crevice corrosion, stress corrosion cracking and corrosion fatigue. Finally, a comprehensive model has been developed for predicting sensitization of Fe-Ni-Cr-Mo-W-N alloys and its effect on localized corrosion. As a vehicle for the commercialization of this technology, OLI Systems has developed the Corrosion Analyzer, a software tool that is already used by many companies in the chemical process industry. In process design, the Corrosion Analyzer provides the industry with (1) reliable prediction of the tendency of base alloys for localized corrosion as a function of environmental conditions and (2) understanding of how to select alloys for corrosive environments. In process operations, the software will help to predict the remaining useful life of equipment based on limited input data. Thus, users will also be able to identify process changes, corrosion inhibition strategies, and other control options before costly shutdowns, energy waste, and environmental releases occur. With the Corrosion Analyzer, various corrosion mitigation measures can be realistically tested in a virtual laboratory.