Stress corrosion cracking environmental influences

Additionally, specific environmental conditions can induce localized corrosion such as temperature, conductivity of the corrosive fluid, or thickness of the liquid corrosive film in contact with the metal. In some cases, both metallurgical and geometric factors will influence behavior, such as in stress-corrosion cracking. Preferential weldment corrosion of carbon steels has been investigated since the 1950s, commencing with the problems on icebreakers, but the problem continues today in different applications. (Bond)5... 

Bucci, R. J., "Environment Enhanced Fatigue and Stress Corrosion Cracking of a Titanium Alloy Plus a Simple Model for the Assessment of Environmental Influence on Fatigue Behavior, Ph.D. dissertation, Lehigh University, Bethlehem, PA, 1970. 

E Gamboa, A Atrens, Environmental influence on the stress corrosion cracking of rock bolts, Engineering Failure Analysis, 2003, 10, 521. 

Bucci, R.J. Environment enhanced fatigue and stress corrosion cracking of a titanium alloy plus a simple model for the assessment of environmental influence on fatigue behavior. PhD Dissertation, Lehigh University, Bethlehem (1970)... 

The fracture behaviour of glasses is also influenced by humidity. An increase of the relative humidity results in an increase of fracture velocity. Wiederhorn [562] provided an explanation of the mechanism of the impact of moisture on the fracture behaviour. Michalske and Freiman [356] discussed the molecular mechanism of stress corrosion in vitreous silica, which depends on the environmental conditions. The increase in the fracture velocity in glasses with increase in environmental moisture content is due to the chemical reaction between glass with water at the crack tip. The transport rate of water to the crack tip influences the fracture behaviour. These effects are of particular importance for the mechanical shaping of glasses in the presence of aqueous lubricants. 

It is often difficult to conduct laboratory tests in which both the environmental and stressing conditions approximate to those encountered in service. This applies particularly to the corrosive conditions, since it is necessary to find a means of applying cyclic stresses that will also permit maintenance around the stressed areas of a corrosive environment in which the factors that influence the initiation and growth of corrosion fatigue cracks may be controlled. Among these factors are electrolyte species and concentration, temperature, pressure, pH, flow rate, dissolved oxygen content and potential (free corrosion potential or applied). 

Influence of Chemicals—Environmental Stress Cracking. In metallurgy, corrosive stress cracking is the simultaneous interaction of a certain... 

Frequency. Cyclic load frequency is die most important variable that influences corrosion fatigue for most material, environment, and stress intensity conditions. The rate of environmental cracking above that produced in vacuum generally increases with decreasing fiequency. Frequencies exist above which corro-... 

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