Stress Corrosion Cracking Behavior of Spring Steel in Aggressive Corrosion Environment

An experimental study was carried out to investigate the stress corrosion cracking behavior of spring steel in acidic media by constant extension to fracture. The majority of the spring material requirements are met with carbon steel, alloy steel, and corrosion-resistant steel. Some of the desired mechanical properties are yield strength, toughness, and fatigue strength to withstand the various service loads and unexpected jerks during the working environment. The service performance of the spring steel is closely related to susceptibility to corrosion. The cracks induced due to environmental service condition under the influence of service load affects the performance of the engineering component. The combined effect of this applied load and environmentally induced cracks may lead to delayed but catastrophic failure. Stress corrosion cracking (SCC) of spring steel was investigated at room temperature in nitric acid using a constant extension method. The test was performed on treated and untreated tensile cylindrical specimens exposed to a corrosive environment. Experimentation was carried out according to ASTM E8 standards. The tensile loading of these corroded specimens has yielded significant changes in the mechanical properties revealing the influence of stress corrosion cracking. The effect of stress corrosion is witnessed in terms of change in yield strength, ultimate strength, and ductility of the untreated and treated tensile test specimens. The anodic dissolution of material led to the loss in cross-section resulting in varied tensile behavior of stress corroded specimens.