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Stainless steels are widely used in applications where both the mechanical properties of steels and high corrosion resistance are required. There is continuous research to enable stainless steel components to be produced in a more economical way and be used in more harsh environments. A way to achieve this is to correlate the service performance with the production processes.

The central theme of this thesis is surface integrity and corrosion, especially the stress corrosion cracking behavior, after grinding processes. Controlled grinding parameters, including abrasive grit size, machine power and grinding lubricant, were used and the resulting surface properties studied for austenitic 304L and duplex 2304 stainless steels. The abrasive grit size effect was found to have a larger influence. Surface defects, a highly deformed surface layer and the generation of a high level surface tensile residual stresses along the grinding direction were observed as the main types of damage. 

The effect of grinding on stress corrosion cracking behavior of austenitic 304L, ferritic 4509 and duplex 2304 stainless steels in chloride-containing environments was also investigated.  The abrasive grit size effect on corrosion behavior for the three grades was compared. Grinding-induced surface tensile residual stress was suggested as the main factor to cause micro-cracks on the ground surface for 304L and 2304; for 4509, grinding-induced grain fragmentation was considered as the main factor for the initiation of extensive micro-pits. For duplex 2304, the microstructure and micro-notches in the as-ground surface also had significant influence. Depending on the surface conditions, the actual loading by four-point bending was found to deviate from the calculated value using the formula according to ASTM G39 by different amounts. The knowledge obtained from this work can provide guidance for choosing appropriate stainless steel grades and grinding parameters; and can also be used to help understanding the failure mechanism of ground stainless steel components during service.