EBSD analysis of cyclic load effect on final misorientation distribution of post-mortem low alloy steel: A new method for fatigue crack tip driving force prediction

2018 ◽  
Vol 113 ◽  
pp. 264-276 ◽  
Author(s):  
Shao-Shi Rui ◽  
Yi-Bo Shang ◽  
Yue Su ◽  
Wenhui Qiu ◽  
Li-Sha Niu ◽  
...  
Keyword(s):  
Fatigue Crack ◽  
Alloy Steel ◽  
Driving Force ◽  
Cyclic Load ◽  
New Method ◽  
Post Mortem ◽  
Low Alloy Steel ◽  
Load Effect ◽  
Misorientation Distribution ◽  
Force Prediction

Further Development of a Model for Predicting Corrosion Fatigue Crack Growth in Reactor Pressure Vessel Steels

1987 ◽  
Vol 109 (3) ◽  
pp. 340-346 ◽  
Author(s):  
J. D. Gilman
Keyword(s):  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Alloy Steel ◽  
High Stress ◽  
Time Dependent ◽  
Crack Advance ◽  
Low Alloy Steel ◽  
Time Rate ◽  
Paris Law

Analysis of fatigue crack growth data for low-alloy steel shows that the influence of cyclic frequency in simulated LWR environments can be interpreted as the superposition of a time-dependent, corrosion-assisted crack growth rate upon an increment predicted by a Paris law. The time-dependent component increases monotonically to a maximum of about 6×10−5 mm/s as stress cycling becomes more aggressive. A useful measure of aggressiveness is the average time rate of crack advance due to the Paris law component alone; i.e., AΔKn × frequency. The result suggests that current ASME Code methods for flaw assessment are highly conservative in some regimes of stress and frequency, but there is a possibility of growth rates well above the ASME XI, Appendix A curves in a very low-frequency, high-stress regime. An upper bound to the time rate of corrosion-assisted crack growth in low-alloy steel is well supported by the data. The threshold conditions for the onset of this high rate are less well defined and require further investigation.

Fatigue Crack Thresholds Significantly Affected by Thermo-Mechanical Loading Histories in an Austenitic and a Ferritic Low Alloy Steel

2014 ◽  
Vol 891-892 ◽  
pp. 1295-1301
Author(s):  
Masakazu Okazaki ◽  
M. Muzvidziwa ◽  
R. Iwasaki ◽  
Naoto Kasahara
Keyword(s):  
Fatigue Crack ◽  
Alloy Steel ◽  
Mechanical Loading ◽  
Structural Reliability ◽  
Repair Process ◽  
Fluid Temperature ◽  
Low Alloy Steel ◽  
History Effects ◽  
High Temperature Structural Material ◽  
High Cycle Thermal Fatigue

High cycle thermal fatigue failure of pipes induced by fluid temperature change is one of interdisciplinary issues to be concerned for long term structural reliability of high temperature structural material and components in energy systems. In order to get basic understanding on this article. the fatigue crack propagation tests were carried out in a low alloy steel and an austenitic stainless steel those were subjected to typical kinds of thermo-mechanical loading histories those included a simulated weld repair process. It was shown experimentally that the thermo-mechanical histories left their individual effects along the prior fatigue crack wake, resulting in significant change in the fatigue crack threshold. Some proposes are presented to predict those history effects.

Sign in / Sign up

Export Citation Format

Share Document