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Corrosion and Fatigue Testing of Microsized 304 Stainless Steel Beams Fabricated by Femtosecond Laser

Qiang Zhang,Xingpeng Guo,Nengli Dai,Peixiang Lu,

材料科学技术学报 , 2009,
Abstract: The 304 stainless steel (SS) microcantilever specimens with dimensions of 30 μm×30 μm×50 μm (thickness× width×length) were fabricated by femtosecond (fs) laser. The microsized cantilevers of good quality with structure and dimensions according commendably with that of the designed cantilever were obtained. The result shows that fs laser micromachining is a promising method for directly fabricating metallic microcomponents. Corrosion and fatigue properties of microsized specimens were carried out on the microsized 304 SS cantilever beams by a newly developed fatigue testing machine. The results show that the microsized 304 SS specimens appear to have an improved resistance towards localized corrosion compared to ordinary-sized 304 SS specimens after the static corrosion testing. The testing result shows that the presence of corrosive solution reduces the fatigue lifetime of the 304 SS specimen by a factor of 10-100. The maximum bending loads measured by fatigue testing machine decrease rapidly at the terminal stage of environment assisted fatigue testing. Corrosion fracture first occurred at the range of notch with a higher tensile bending stress, and exhibited clear evidence of trans-columnar fracture detected by SEM (scanning electron microscopy).
JSLu,IOdneval,CLeygraf College of Chemical Engineering,Zhejiang University of Technology,Hangzhou,China,
,I.Odneval and C.Leygraf College of Chemical Engineering,Zhejiang University of Technology,Hangzhou,China

金属学报(英文版) , 1999,
Abstract: Atmospheric corrosion of 304 and 316 stainless steels was studied by field exposure test, in which rain water was collected and analyzed by atomic absorption spectroscope (AAS). Emphasis was put on the dissolution of chromium and nickel from the stainless steels by atmospheric corrosion and rain runoff. AAS analyses shows that the amounts of yearly chromium and nickel dissolution were less than 150ng/cm 2 and 50ng/cm 2 respectively for both 304 and 316 stainless steels. XPS analysis reveals the marked Cr enrichment on the 316 stainless steel after one year field exposure. SEM shows the morphology of corrosion pits on the steel surfaces.
Corrosion Behaviour of Stainless Steel 304 Electroplated with Zinc Followed by Blue Passivation  [cached]
H.B. Sherine,C.C. Rajakumari,S. Rajendran
Portugaliae Electrochimica Acta , 2011,
Abstract: The corrosion resistance of three stainless steel materials, namely, stainless steel (SS), stainless steel electroplated with zinc (SS-Zn) and stainless steel electroplated with zinc followed by blue passivation (BP), has been evaluated in an aqueous solution containing 3.5% NaCl. A potentiodynamic polarization study and AC impedance spectra have been used to investigate the corrosion behaviour of these metals. The corrosion resistance of these materials in 3.5% NaCl increased in the following order: SS>SS+Zn+BP>SS+Zn.
Assessment of Galvanic Corrosion in Galvanic Couples of Sensitized and Nonsensitized AISI Type 304 Stainless Steel in Nitric Acid
M.G. Pujar, N. Parvathavarthini, R. K. Dayal and H. S. Khatak
International Journal of Electrochemical Science , 2008,
Abstract: Waste vault tanks made of 304 stainless steel (SS) meant for the storage of high level liquid waste of 6M HNO3 showed precipitation of M23C6 in heat affect zone (HAZ) in the weldments and high corrosion rates in boiling nitric acid test (ASTM A262 Practice C test). In this connection a study of possible galvanic corrosion effect at the junction of sensitized HAZ and the adjacent base metal in 304 SS in sulphuric as well as nitric acid, was undertaken. The galvanic couples were prepared using sensitized 304SS as the anodes, and the base metal as the cathodes, electrically connected in different anode to cathode ratios. Potentiodynamic anodic polarization studies were conducted in deaerated 0.5M sulphuric acid whereas electrochemical noise (ECN) experiments were performed in 3M deaerated nitric acid at room temperature as well as 60°C. The data analysis of current and potential signals was conducted using statistical methods; the data was analysed in the frequency domain using Maximum Entropy Method (MEM). The corrosion rates observed in nitric acid medium at room temperature did not show enhanced corrosion rate due to galvanic coupling. However, the corrosion rates were higher at 60°C in the same medium. Based on these results, a drastic rise in corrosion rate and the subsequent failure of the waste vault tank was not expected.
Corrosion potential of 304 stainless steel in sulfuric acid
Journal of the Serbian Chemical Society , 2006,
Abstract: The potentiodynamic study of the electrochemical behavior of austenitic 304 stainless steel in deaerated aqueous sulfuric acid of pH 1 revealed that the steel achieved a stable corrosion potential of ca. – 0.350 V (SCE) independent of whether the electrode had previously been cathodically “activated” or anodically passivated. It was also shown that the experimentally observed anodic peak was not the usually obtained anodic passivation peak, as is the case with a number of metal, but an artifact due to the anodic oxidation of hydrogen absorbed during the previously employed cathodic polarization and hydrogen evolution, intended to activate the initially passive surface, or even hydrogen absorbed on the open circuit potential. It was shown that this potential establishes and electrochemical corrosion potential of the Wagner–Traud type due to the evolution of cathodic hydrogen on a passivated steel surface and anodic metal dissolution through the passive layer. It was impossible to activate 304 stainless steel in sulfuric acid of pH 1 by cathodic polarization, and the usually observed anodic peak obtained under these conditions should not be considered as an active metal dissolution process and a passivation anodic peak, but rather as an artifact due to the electrochemical oxidation of the in the steel absorbed hydrogen.
Comparison of Aggressiveness Behavior of Chloride and Iodide Solutions on 304 and 304L Stainless Steel Alloys  [PDF]
Shaymaa Mahdi Salih, Ibtehal K. Shakir, Abdulkareem M. A. Al-Sammarraie
Materials Sciences and Applications (MSA) , 2017, DOI: 10.4236/msa.2017.812065
Abstract: The aggressive effect of chloride anion in comparison to iodide anion on the pitting corrosion attack of 304 and 304L stainless steel (SS) alloys was investigated by using the cyclic potentiodynamic polarization test at 0.6 M Sodium Halide salts (NaX) solution and different temperatures. The two alloys 304 and 304L SS suffered from severe pitting corrosion at room temperature up to 50°C in a chloride containing solution with the higher resistance observed for 304L in comparison to the 304 while on pits were detected in iodide solution for both alloys. The pitting potentials of the two alloys in 0.6 M NaCl solution reduced with the increase of the temperature. Examination of the alloys’ surfaces was conducted by using the scanning electron microscopes where it revealed that the occurrence of pitting attack seems like hemispherical or irregular pits with different sizes.
Corrosion Behavior of Mild Steel and SS 304L in Presence of Dissolved Copper  [PDF]
M. Mobin, Hina Shabnam
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2010, DOI: 10.4236/jmmce.2010.912081
Abstract: The failure of steel components in multistage flash (MSF) desalination or power plants as a result of the deposition of carryover heavy metals/oxides is a common problem and reported by many authors. The present investigation was undertaken to study the corrosion behavior of mild steel and AISI 304L SS in presence of dissolved Cu ions under different experimental conditions. The experimental conditions include: variation in aqueous medium, Cu ion concentration, pH and flow condition. The corrosion rate of mild steel and SS 304L in presence of different concentration of Cu was determined by weight loss measurements and solvent analysis of iron ions into the test solution after completion of immersion. The amount of Cu ions present in the test solution after completion of immersion was also estimated using Atomic absorption spectrophotometer. The pH of the test solution was monitored during the entire period of immersion. Electrochemical techniques like free corrosion potential measurements and potentiodynamic polarization measurements were carried to find out the role of Cu ions on the corrosion behavior of mild steel and SS 304L. The effect of Cu on corrosion rate of mild steel is quite pronounced and follows interesting trend. However, SS 304L is not affected either in distilled water or artificial seawater and do not show any significant variation in corrosion rates in presence of Cu ions.

FANG Zhi,WU Yinshun,LI Jiuqing,SUN Dongbai,

腐蚀科学与防护技术 , 1995,
Abstract: There are two potential ranges for 304L stainless steel sensitive to intergranular corrosion in 0.5mol / LH2SO4+10(-3)mol/L CH3CSNH2 solution. One is active-passive transitive potential range, the critical potential for the other is 1040mV(SCE). The material is sensitive to intergranular corrosion at potentials above this value. The susceptibility to intergranular corrosion of 304L stainless steel can be judged by potentic-static method. The bigger the current density andthe slope of current density-time curves at a certain potential, the more susceptive to intergranularcorrosion.
Corrosion in Tap Water and Hot Water Supply Facilities of Stainless Steel Type 304 Pipes  [PDF]
Noriyuki Tanaka, Shigeru Sato, Ippei Watanabe, Yutaka Yamada, Osamu Sakurada
Materials Sciences and Applications (MSA) , 2018, DOI: 10.4236/msa.2018.91005
Abstract: We performed corrosion case study and corrosion tests to assess the corrosion resistance of stainless steel type 304 pipes in tap water and hot water facilities. Circulating test equipment used for corrosion tests and two types of sample, plates and straight pipe specimens, were examined under different conditions of residual chlorine concentration in the test water. The results of case study analysis indicated that high degrees of pitting corrosion occurred on straight pipes with inner diameter < 50 mm. The results of corrosion tests showed that the residual chlorine concentration around the pitting corrosion of stainless steel type 304 was greater than 0.3 mg/L in the plate, regardless of the remaining chlorine concentration in the straight pipe specimens. These results suggest that straight pipes have higher corrosion susceptibility because of bending during production.
Corrosion Inhibition of 304 SS in Hydrochloric Acid Solution by N - Furfuryl N'- Phenyl Thiourea
Herle,R.; Shetty,P.; Shetty,S.D.; Kini,U.A.;
Portugaliae Electrochimica Acta , 2011,
Abstract: the inhibition of corrosion of 304 ss in 2 n hcl solutions by n - furfuryl - n' phenyl thiourea (fptu) has been investigated using potentiodynamic polarization techniques. the results obtained reveal that fptu performs excellently as anodic inhibitor (ie> 93%) for 304 ss in hcl solution. the inhibitor functions through adsorption following temkin?s adsorption isotherm, and the inhibition was governed by physisorption mechanism. the thermodynamic parameters deduced for the adsorption process reveal spontaneous adsorption of the compound on the alloy steel surface.
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