Effect of corrosion on the high cycle fatigue strength of martensitic stainless steel X12CrNiMoV12-3

TLDR: In this article, the effects of corrosion on the high cycle fatigue (HCF) strength of a high mechanical strength martensitic stainless steel (X12CrNiMoV12-3) that is used in aeronautic applications were addressed.

About: This article is published in International Journal of Fatigue.The article was published on 2013-02-01 and is currently open access. It has received 45 citations till now. The article focuses on the topics: Corrosion fatigue & Martensitic stainless steel.

Figures

Figure 1: X12CrNiMoV12-3 stainless steel microstructure after heat treatment ................................. 16

Figure 4: Median S-N curves (survival probability Ps = 0.5) in air and in the aqueous solutions at 120 Hz........................................................................................................................................................... 19

Figure 5: Crack initiation sites in air and under corrosion fatigue in the aqueous solutions ................ 20

Figure 8: Relation between normalized stress amplitude and (a) initiation time of potential decrease from Ebara [9] and (b) duration of the potential decrease for our corrosion fatigue tests .................. 23

Figure 3: In-situ corrosion fatigue cell with potentiostatic measurements. The specimen is isolated from the fatigue testing machine (Vibrophore) .................................................................................... 18

Figure 6: Linear scan voltammetry test on a specimen without cyclic stress in 0.1 M NaCl + 0.044 M Na2SO4 ................................................................................................................................................... 21

Frequently asked questions

Q1. What contributions have the authors mentioned in the paper "Effect of corrosion on the high cycle fatigue strength of martensitic stainless steel x12crnimov12-3" ?

This paper addresses the effects of corrosion on the high cycle fatigue ( HCF ) strength of a high mechanical strength martensitic stainless steel ( X12CrNiMoV12-3 ) that is used in aeronautic applications. The electrochemical behaviour of the passive film was investigated during fatigue testing in a NaCl aqueous solution by monitoring the free potential and through electrochemical impedance spectroscopy ( EIS ). 

Q2. What are the future works mentioned in the paper "Effect of corrosion on the high cycle fatigue strength of martensitic stainless steel x12crnimov12-3" ?

In the future, a corrosion fatigue crack initiation model considering the coupling between the environment and cyclic loading should also be developed. 

Q3. What is the loading frequency of a passive film?

The possible effect of the loading frequency in corrosion fatigue is related to the repassivation rate after local ruptures in the passive film. 

Q4. What is the effect of the aqueous solution on the corrosion strength?

The authors conclude that the corrosive effect (depassivation of the material) is not dependent solely on the chloride content in the environment because for the 0.1 M Na2SO4 solution and the distilled water, the decreasing of the fatigue strength is also important. 

Q5. What was the free potential in the corrosion fatigue test?

For the corrosion fatigue test in the 0.1 M Na2SO4 aqueous solution without chlorides, the free potential also decreased to around -0.4 V/SCE under cyclic loading. 

Q6. How many locations were measured to evaluate the thickness of the passive film?

Measurements were performed at ten different locations on the specimen surface in order to evaluate the thickness uniformity of the passive film. 

Q7. What was the free potential recorded during cyclic loading?

The free potential was recorded during cyclic loading (corrosion fatigue tests) in the same environment (0.1 M NaCl + 0.044 M Na2SO4 aqueous solution). 

Q8. What is the value of the free potential in the corrosion fatigue test?

No free potential decrease was observed forspecimens which did not fail after 107 cycles under a stress amplitude equal to the median fatigue strengths in the aqueous solution (σDR=-1 (NaCl) or σ D R=0.1 (NaCl)). 

Q9. What is the common method used to calculate the coefficients of the CPE, Rc?

A fitting program (Zsimwin) was used to provide the coefficient values of the CPE, Rct and Rs. Figure 10 shows that the calculated curves agree with the experimental values in the investigated frequency range.