Stainless steel 316L, corrosion

Stainless steel 316L material used for piping and equipment shows considerable corrosion resistance because of the beneficial effect of molybdenum on the surface properties. It is also observed that the surface treatment (pre-reduced, polished, passivated and chemically treated surfaces) of stainless steel equipment and piping reduces the corrosion process in seawater applications. The corrosion resistance of stainless steel in seawater applications can also be enhanced by bulk alloying the stainless steel with nitrogen, chromium, molybdenum and nickel by converting the stainless steel into super austenitic stainless steel. From leaching studies it is also observed that the release of iron, chromium and nickel from the super austenitic stainless steel to seawater is considerably... 

Chew, K.K., Zein, S.H.S., and Ahmad, A.L. (2012) The corrosion scenario in human body stainless steel 316L orthopaedic implants. Nat. Sci., 4, 184-188. 

Stainless steel, 316L and 304L, is the preferred material of constmction for shipment and storage of alkanolamines, if product quahty is of importance. Aluminum can be used for short term transport, at temperatures below 60°C, for the pure amines. Plastic liners have not been found acceptable for all alkanolamines. Phosphatized-lined steel dmms are used for transport of ethanlomaines and isopropanolamines, except MEA, which is shipped in high density polyethylene dmms to maintain low product color. Monoetbano1 amine and monoisopropanolamine are classified as DOT corrosive Hquids. 

The author was once involved in corrosion assessment for an industry. The case was about two cracked stainless steel 316L tubes with a service temperature of less than 60°C with water as the fluid inside them. X-ray fluorescence (XRF) results for the collected corrosion products are shown in Figure 4.53. 

Parsapour, A. Fathi, M. H. Salehi, M. In vitro evaluation of the corrosion behavior and biocompatibihty of surface treated and metallic coated stainless steel 316L implants. Proc. 1st Jordanian International Conference of Materials Science and Engineering, Al-Balqa Applied University, Al-Salt, Jordan, 3-5 May 2005, pp. 91-99. 

L stainless steel Increased corrosion rate Polarization resistance method static conditions 10% serum (Williams et al, 1988)... 

The behavior of 316L stainless steel in corrosive conditions was improved upon deposition of nanohybrid coatings based on PMMA-Zr02- The coatings were deposited via dip-coating of sols prepared by mixing zirconium propoxide and... 

Javaherdashti in his investigation regarding the mechanical and electrochemical behaviour of mild steel, stainless steel 316L, and duplex stainless steel SAF2205 found that when mild steel is exposed to a culture of IRB, in comparison with an abiotic environment it shows lesser times of failure, therefore implying that IRB could actually enhance corrosion [89]. Figure 4.20 illustrates the typical slow strain rate SCC behaviour of mild steel in a culture of IRB. 

Armco NITRONIC 50 Stainless Steel provides a combination of corrosion resistance and strength. This austenitic stainless steel has corrosion resistance greater than that provided by Types 316, 316L, 317 and even 317L, pius approximately twice the yield strength at room temperature. In addition, Armco NITRONIC 50 has very good mechanical properties at both elevated and sub-zero temperatures. 

Gegelova, N, B., Mudzhiri, Y. N., Knyazheva, V. M. and Topchiashvili, L. I., Determination of Intercrystalline Corrosion Tendency of Stainless Steel by Potentiodynamic Method , Zashch. Metal., 8, 420 (1972) C.A., 77, 121422n van der Horst, J. M. A., Grain Boundary Attack of 316L Stainless Steel in Ammonia-rich Environments , J. Electrochem. Soc., 119, 216C (1972)... 

One of the most serious corrosion problems associated with type 316 stainless steel is its susceptibility to crevice corrosion. The incidence and extent of this type of corrosion in surgical implants was stressed by Scales eta/. who reported the presence of crevice corrosion in 24% of type 316L bone plates and screws examined after removal from patients. This record however compared favourably with the presence of crevice corrosion in 51 % of 18-8 stainless plates, demonstrating the superiority of the molybdenum-containing grade. 

The specimen design used in the study by Rostoker et al. was such that it simulated both galvanic coupling and crevice conditions. Specimens were immersed in a 1% saline solution at 37 C, and examined by optical microscopy after exposures of a few to 100 days. No corrosion was observed on Ti-6A1-4V when the alloy was either uncoupled, coupled with itself (simple crevice). Or coupled with type 316L stainless steel, cast Co-Cr-Mo... 

Bundy, K. J., Vogelbaum, M. A. and Desai, V. H., The Influence of Static Stress on the Corrosion Behaviour of 316L Stainless Steel in Ringer s Solution , Journal of Biomedical Materials Research, 20, 493-505 (1986)... 

Sheehan, J. P., Morin, C. R. and Packer, K. F., Study of Stress Corrosion Cracking Susceptibility of Type 316L Stainless Steel In-Vitro , in Corrosion and Degradation of Implant Materials, Second Symposium , (Eds) A. C. Fraker and C. D. Griffin, 57-72 ASTM Publication STP 859, Philadelphia (1985)... 

Selective corrosion in the heat-affected zone of a weld occurs most commonly when unstabilised stainless steels are used in certain environments. The obvious answer is to use an extra-low-carbon grade of stainless steel, e.g. types 304L, 316L or a stabilised grade of steel, e.g. types 321 and 347. Knifeline attack at the edge of a weld is not commonly encountered and is seldom predictable, and it must be hoped that it is revealed during preliminary corrosion testing. 

After purification, 316L grade stainless steel is used. This is resistant to corrosion and is electropolished and passivated to reduce roughness, which may act as sites for bacterial growth and future corrosion. 

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