Huey Corrosion Resistance for Urea Grade 316Lmod Stainless Steel Tube

The effect of different solution heat treatment processes on Huey corrosion properties of urea grade 316Lmod stainless steel tube was studied by Huey test. The surface corrosion morphology of the specimens with different heat treatment processes during Huey test was observed by optical microscope and scanning electron microscope, and the corrosion mechanism of Huey test was analyzed. The results show that the average corrosion rates of the specimens solution heat treated at 1 000-1 150 ℃ decrease with the increase of solution temperature, but the Huey corrosion resistance increases with the increase of solution temperature. With the increase of corrosion test cycle, the number of corrosion pits on grain boundaries of specimens, the area of corrosion pits and the corrosion rate increase. With the increase of solution temperature, the number of corrosion pits and the total area of corrosion pits on the grain boundary of specimens in the same corrosion test cycle decrease, and the Huey corrosion resistance improves. The average grain size is proportional to the solution temperature, the larger the average grain size is, the better the non sensitized intergranular corrosion resistance of the material is, and the better the Huey corrosion resistance is.