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During the past three decades the chromium-nickel stainless steels have become invaluable tools for the handling of corrosive chemicals. In numerous media, these materials provide completely satisfactory service. In certain conditions of heat treatment, when exposed to specific media, they may exhibit a type of attack known as intergranular corrosion, which can seriously affect their usefulness. Austinitic stainless steels, such as AISI Types 302, 304, 316, and 317 can be rendered susceptible to such attack to exposure in the temperature range of 900-1400F. This "sensitization" is generally attributed to the precipitation of chromium carbides at the grain boundaries which lowers the effective chromium contension resistance near the grain bound phenomenon has long been recognized, and has led to the development of low carbon grades and columbium or titanium stabilized grades of stainless steels which possess greatly improved resistance to carbide precipitation.