Susceptibility of 316L stainless steel to crevice corrosion in submersible solenoid valve

Abstract

The susceptibility of 316L stainless steel to crevice corrosion was investigated by using immersion test and electrochemical test. Three kinds of crevices including 316L-to-polytetrafluoroethylene (PTFE) crevice, 316L-to-fluoroelastomeric (FKM) crevice and 316L-to-316L crevice were tested in artificial seawater at 508C. The results indicate that 316L stainless steel specimen is the most susceptible to crevice corrosion when it is coupled to 316L stainless steel crevice former, while it is the least susceptible when it is coupled to FKM crevice former. It suggests that during submersible solenoid valve design, the crevice of metalto-metal should be moderately large so that crevice corrosion can not initiate and propagate, and FKM O-ring rather than PTFE O-ring should be selected as obturating ring. The corroded surface morphology was investigated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Three regions including passive region, active region and variable region can be observed on crevice corrosion sites.

Experimental study of galvanic corrosion behaviour of carbon fibre composite coupled to aluminium in artificial seawater

“…The galvanic corrosion tests were performed in artificial seawater prepared with deionised water and sea salts; the detailed composition of the solution is given in Table 1 20. The concentration of the artificial seawater is considered as 3·5%.…”

Optimal Design Based on Dynamic Characteristics and Experimental Implementation of Submersible Electromagnetic Actuators

“…When the coil is energized by DC voltage, the plunger of the SEMA retracts upward and extends downwards by releasing the stored energy from the spring [13] and [19]. [13] The cover of the actuator is made of AISI 316L austenitic stainless steel due to its high corrosion resistance to seawater, high strength, and high durability [20] and [21]. However, AISI 316L stainless steel is nonmagnetic.…”