Abstract One of the great problems faced in the production of concentrated sulfuric acid is its storage and transportation because this acid is very aggressive. Carbon steel and austenitic stainless steel (ASTM A 36; API 5L GrB; AISI 316L) are the most commonly used alloys. When these alloys come into contact with concentrated sulfuric acid there is an immediate acid attack with the formation of a protective layer on the metallic surface. Corrosion rate mean values of these alloys in concentrated sulfuric acid can be found in the literature; however data on the variation of the corrosion rates as a function of immersion time are rare. This type of study is important because it allows estimating the time of formation of the protective layer and the amount of hydrogen formed soon after the metal contact with the acid. This paper aims to present curves of variation of corrosion rate as a function of immersion time obtained for ASTM A 36 and API 5L GrB carbon steels and AISI 316L stainless steel in sulfuric acid at concentrations of 93.5 % 96 % and 98 % at room temperature. Curves for a high corrosion resistant alloy (Alloy 20) are also presented.