Increasing the Resistance of Automobile Sheet to Atmospheric Corrosion by Optimizing its Chemical Composition and the Parameters of the Manufacturing Process

A method involving alternating immersion in a 3.5% NaCl solution has been developed for corrosion tests of automobile sheet. Results obtained from 30 cycles of tests (10 + 50 min) of specimens of steels 08Yu, 08ps, 08YuP, 08YuDP, 08GSYuT, and IF established the dependence of the steel's unit weight gain from corrosion products on its combined content of carbon and silicon: steels with a lower content of these elements show a smaller gain in weight, i.e., they exhibit greater corrosion resistance. Steel alloyed with copper (0.23-0.34%) and phosphorus (0.06-0.08%) - the production of which has been mastered by the company Severstal' -- has the highest resistance to corrosion. Use of the method makes it possible to rank grades of automobile sheet in one of three corrosion-resistance classifications in relation to their chemical composition and the parameters of the production process.[PUBLICATION ABSTRACT]