The fatigue crack initiation at the interface between matrix and δ-ferrite in 304L stainless steel

1998 ◽  
Vol 39 (10) ◽  
pp. 1407-1412 ◽  
Author(s):  
Byung Sup Rho ◽  
Hyun Uk Hong ◽  
Soo Woo Nam
Keyword(s):  
Stainless Steel ◽  
Fatigue Crack ◽  
Crack Initiation ◽  
Fatigue Crack Initiation ◽  
304L Stainless Steel ◽  
Δ Ferrite

Fatigue Crack Initiation of 304L Stainless Steel in Simulated PWR Primary Environment: Relative Effect of Strain Rate

2012 ◽  
Author(s):  
Nicolas Huin ◽  
Kazuya Tsutsumi ◽  
Laurent Legras ◽  
Thierry Couvant ◽  
Dominique Loisnard ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Fatigue Crack ◽  
Fatigue Life ◽  
Crack Initiation ◽  
Strain Rate ◽  
Early Stage ◽  
Laboratory Data ◽  
Fatigue Crack Initiation ◽  
304L Stainless Steel ◽  
Pressurized Water

The French Regulatory Commission insisted on a survey justifying the assumed mechanical behavior of components exposed to Pressurized Water Reactor (PWR) water under cyclic loading without taking into account its effect. In the US and Japan, the fatigue life correlation factors, so called Fen, are formulated and standardized on the basis of laboratory data to take into account the effect on fatigue life evaluation. However, the current fatigue codification, suffers from a lack of understanding of environmental effects on the fatigue lives of stainless steels in simulated hydrogenated PWR environments. Samples tested in a recent study were analyzed to highlight the strain rate effect (within a range 0.4%/s to 0.004%/s) at the early stage of fatigue life in PWR primary environment for a 304L stainless steel. The deleterious effect of PWR primary environment on fatigue crack initiation was observed with a quantitative microscopic approach. Multi scale observations of oxide morphology and microstructure were carried out from common optical microscopy using recent technologies such as 3D oxide reconstruction, and DualBeam observations.

scholarly journals Toward consistent fatigue crack initiation criteria for 304L austenitic stainless steel under multi-axial loads

2015 ◽  
Vol 75 ◽  
pp. 57-68 ◽  
Author(s):  
Bai-Mao Lei ◽  
Van-Xuan Tran ◽  
Saïd Taheri ◽  
Jean-Christophe le Roux ◽  
François Curtit ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Fatigue Crack ◽  
Austenitic Stainless Steel ◽  
Crack Initiation ◽  
Fatigue Crack Initiation ◽  
Axial Loads

Environmental Effects on Fatigue Crack Initiation in 2.25 Cr-1 Mo Steel and 316L Stainless Steel

1988 ◽  
Vol 110 (3) ◽  
pp. 240-246
Author(s):  
V. K. Mathews ◽  
T. S. Gross
Keyword(s):  
Stainless Steel ◽  
Fatigue Crack ◽  
Crack Initiation ◽  
Room Temperature ◽  
316L Stainless Steel ◽  
Silicone Oil ◽  
Fatigue Crack Initiation ◽  
Type A ◽  
Order Of Magnitude ◽  
Number Of Cycles

Blunt notch fatigue crack initiation tests for Type A387 2.25 Cr-1 Mo steel and 316L stainless steel were performed in air at room temperature, in silicone oil at room temperature, in V-131B coal process solvent at 100°C, and in chlorine-modified V-131B coal process solvent at 100°C. For both steels the most damaging environment was room temperature air. The number of cycles to initiate a crack were almost identical in the coal process solvent and the silicone oil for the Type A-387 steel. These two environments resulted in the longest crack initiation lifetime for the Type A-387 steel. The crack initiation lifetime for the Type A-387 steel in the chlorine modified V-131 B coal process solvent was roughly a factor of five less than the lifetime in the silicone oil and the unmodified coal process solvent. The crack initiation lifetime for the Type A-387 steel in room temperature air was a factor of 30 less than the lifetime in the silicone oil or the unmodified coal process solvent. The improvement of the crack initiation lifetime for the Type A-387 steel in the unmodified coal process solvent and the silicone oil is attributed to protection of the material from embrittlement from room temperature air. The decrease in crack initiation lifetime in the chlorine modified coal process solvent indicates that chlorine can be an active embrittling agent in the coal process solvent. The crack initiation lifetime for 316L stainless steel was longest in the silicone oil. The lifetime decreased somewhat in the unmodified coal process solvent with a further decrease for the chlorine modified coal solvent. The crack initiation lifetime in air was an order of magnitude lower than the lifetime in the silicone oil. The silicone oil and the coal process solvent apparently protected the 316L stainless from the embrittlement in air. However, the coal process solvent is not entirely inert as in the case of Type A-387 steel. The chlorine is an active embrittling agent for the 316L stainless steel in the coal process solvent.

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