Incipient corrosion behavior and mechanical properties of low-alloy steel in simulated industrial atmosphere

•The corrosion morphology on the different surfaces of the specimens are different.•Salt spray tests of steel specimens could be considered as a stochastic process.•With same corrosion time, the mass loss ratio conformed to the normal distribution.•The corrosion process could be described by a power model or an exponential model.•Plastic deformation performance was sensitive to corrosion. Low-alloy steel is widely used in the structures. However, the corrosion problem is very common for low-alloy steel, which would result in the degradation of mechanical properties and the decrease of effective area of steel member. In this paper, the incipient corrosion behavior and mechanical properties of low-alloy steel were studied. Dog-bone steel specimens were artificially corroded through salt spray tests. Based on the experimental results, the incipient corrosion process was detailed presented, and different characterizations of the bottom surface and the top surface of the corroded specimen were analyzed. Then the stochastic distribution function and the time-dependent model of mass loss ratio were presented. At last, through the tensile coupon tests, the influence of corrosion levels on the final elongation ratio, elastic modulus, yielding stress and ultimate strength of low-alloy steel was presented and analyzed.