Short Crack Initiation during Low-Cycle Fatigue in SAF 2507 Duplex Stainless Steel

2007 ◽  
Vol 345-346 ◽  
pp. 343-346 ◽  
Author(s):  
M.C. Marinelli ◽  
Suzanne Degallaix ◽  
I. Alvarez-Armas
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Room Temperature ◽  
Low Cycle Fatigue ◽  
Fatigue Cracks ◽  
Surface Strain ◽  
The Other ◽  
Cycle Fatigue ◽  
Cyclic Tests ◽  
Characteristic Microstructure

In this work, the formation of fatigue cracks is considered as a nucleation process due to the development of a characteristic microstructure formed just beneath the specimen surface. Strain controlled cyclic tests were carried out at room temperature at total strain ranges εt = 0.8 and 1.2% in flat specimens of SAF 2507 Duplex Stainless Steel (DSS). The results show that for this DSS, at εt = 0.8%, the correlation between phases (Kurdjumov-Sacks crystallographic relation) plays an important role in the formation of microcracks. On the other hand, at εt = 1.2%, microcracks initiate in the ferritic phase and the K-S relation does not seem to affect the formation of the cracks.

Fatigue Properties of 316L Stainless Steel

2012 ◽  
Vol 204-208 ◽  
pp. 3786-3789
Author(s):  
Xiao Zhao
Keyword(s):  
Stainless Steel ◽  
Room Temperature ◽  
316L Stainless Steel ◽  
Low Cycle Fatigue ◽  
Fatigue Cracks ◽  
Testing Machine ◽  
Experimental Studies ◽  
Hydraulic Testing ◽  
Fatigue Properties ◽  
Cycle Fatigue

The present paper deals with experimental studies on the tension-tension fatigue properties of 316L stainless steel by using a servo-valve controlled electro-hydraulic testing machine at room temperature. The low cycle fatigue properties of 316L stainless steel were studied and the initiation mechanisms of fatigue cracks were investigated and analyzed with scanning electron microscopy (SEM). Preliminary results indicate that the S-N curve of 316L stainless steel descends linearly in the low cycle regime and fatigue failure initiates from inclusions/defects on the specimen surface.

Low Cycle Fatigue of Nuclear Pipe Components

1974 ◽  
Vol 96 (3) ◽  
pp. 171-176 ◽  
Author(s):  
J. D. Heald ◽  
E. Kiss
Keyword(s):  
Stainless Steel ◽  
Fatigue Life ◽  
Room Temperature ◽  
Fatigue Testing ◽  
Low Cycle Fatigue ◽  
304 Stainless Steel ◽  
Code Design ◽  
Hydraulic Pressure ◽  
Cycle Fatigue ◽  
Cyclic Bending

This paper presents the results of low-cycle fatigue testing and analysis of 26 piping components and butt-welded sections. The test specimens were fabricated from Type-304 stainless steel and carbon steel, materials which are typically used in the primary piping of light water nuclear reactors. Components included 6-in. elbows, tees, and girth butt-welded straight sections. Fatigue testing consisted of subjecting the specimens to deflection-controlled cyclic bending with the objective of simulating system thermal expansion type loading. Tests were conducted at room temperature and 550 deg F, with specimens at room temperature subjected to 1050 psi constant internal hydraulic pressure in addition to cyclic bending. In two tests at room temperature, however, stainless steel elbows were subjected to combined simultaneous cyclic internal pressure and cyclic bending. Predictions of the fatigue life of each of the specimens tested have been made according to the procedures specified in NB-3650 of Section III[1] in order to assess the code design margin. For the purpose of the assessment, predicted fatigue life is compared to actual fatigue life which is defined as the number of fatigue cycles producing complete through-wall crack growth (leakage). Results of this assessment show that the present code fatigue rules are adequately conservative.

Identification and analysis of slip systems activated during low-cycle fatigue in a duplex stainless steel

2008 ◽  
Vol 59 (12) ◽  
pp. 1231-1234 ◽  
Author(s):  
A ELBARTALI ◽  
V AUBIN ◽  
L SABATIER ◽  
P VILLECHAISE ◽  
S DEGALLAIXMOREUIL
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Low Cycle Fatigue ◽  
Slip Systems ◽  
Cycle Fatigue

Microstructural Changes in a Duplex Stainless Steel During Low Cycle Fatigue*

2009 ◽  
Vol 51 (6) ◽  
pp. 359-364 ◽  
Author(s):  
Silvina Hereñú ◽  
Iris Alvarez-Armas ◽  
Alberto Armas ◽  
Suzanne Degallaix ◽  
Adriana Condó ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Low Cycle Fatigue ◽  
Cycle Fatigue ◽  
Microstructural Changes

SEM Study of the Influence of Microstructure on Low Cycle Fatigue Crack Growth in Martensitic Steel I

2018 ◽  
Vol 774 ◽  
pp. 96-100 ◽  
Author(s):  
Tamaz Eterashvili ◽  
Temur Dzigrashvili ◽  
M. Vardosanidze
Keyword(s):  
Room Temperature ◽  
Martensitic Steel ◽  
Low Cycle Fatigue ◽  
Fatigue Cracks ◽  
Cycle Fatigue ◽  
Slip Bands ◽  
Sem Study ◽  
Austenite Grains ◽  
Plastic Zones ◽  
The Impact

Distribution of fatigue cracks in chromium martensitic steel after low cycle fatigue (LCF) tests at room temperature has been studied using SEM, and the experimental evidences of localized plastic flow (LPF) are presented. The influence of the location of LPF and the microstructure elements on the trajectory and growth of microcracks is also considered. The dimensions of plastic zones ahead of macrocrack tip as well as at its edges were measured in the process of crack propagation inside of the sample. The processes occurring in plastic zone, particularly ahead of macrocrack tip, were analyzed. Distribution, orientation and the reasons of slip bands’ formation as well as the microstructure elements at which they were nucleated have been studied. The impact of the slip bands’ orientation on the process of macrocrack growth was also analyzed. In addition the interactions of a crack with the boundaries of former austenite grains, martensitic packets, martensitic laths, slip bands and precipitates have been discussed.

Sign in / Sign up

Export Citation Format

Share Document