Evaluation of grain boundary sliding behavior of SUS316 under low-cycle fatigue fracture at high temperature

The fatigue fracture and the microstructure of Al5Zn2Mg high strength aluminum alloy were observed by OM, SEM and TEM, and the low cycle fatigue properties were tested and analyzed. The results of experimentation show that the low cycle fatigue life of Al5Zn2Mg high strength aluminum alloy is 9.28×104 cycle in R=0.1, f=8Hz, and σmax=0.75σb. The tensile strength is 444MPa. The fatigue fracture is composed of the initiation zone, the propagation zone, and the sudden fracture zone, which is characteristic of a mixed-type fatigue fracture. The fatigue crack initiates in the surface of Al5Zn2Mg aluminum alloy sample, while there is no fatigue striation in fatigue crack propagation zone. The η′(MgZn2) transitional strengthening phases are precipitated in Al5Zn2Mg aluminum alloy, and mostly distributed in grain boundary. The diameter of η′ strengthening phase is fine, about is 10nm. There is none precipitated zone in width nearby the grain boundary

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Grain boundary sliding at high temperature deformation in cold-rolled ODS ferritic steels

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2014.05.040 ◽

2014 ◽

Vol 452 (1-3) ◽

pp. 628-632 ◽

Cited By ~ 13

Author(s):

Yoshito Sugino ◽

Shigeharu Ukai ◽

Bin Leng ◽

Naoko Oono ◽

Shigenari Hayashi ◽

...

Keyword(s):

High Temperature ◽

Grain Boundary ◽

Grain Boundary Sliding ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Ferritic Steels ◽

Boundary Sliding ◽

Cold Rolled

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High-temperature grain boundary sliding behavior and grain boundary energy in cubic zirconia bicrystals

Acta Materialia ◽

10.1016/j.actamat.2004.01.026 ◽

2004 ◽

Vol 52 (8) ◽

pp. 2349-2357 ◽

Cited By ~ 84

Author(s):

Hidehiro Yoshida ◽

Kenji Yokoyama ◽

Naoya Shibata ◽

Yuichi Ikuhara ◽

Taketo Sakuma

Keyword(s):

High Temperature ◽

Grain Boundary ◽

Boundary Energy ◽

Grain Boundary Sliding ◽

Grain Boundary Energy ◽

Cubic Zirconia ◽

Boundary Sliding

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Evaluation of Plastic Workability Limit of Magnesium Alloy by Cavitations in High Temperature Uni and Biaxial Test

Materials Science Forum ◽

10.4028/www.scientific.net/msf.735.67 ◽

2012 ◽

Vol 735 ◽

pp. 67-72

Author(s):

Kunio Funami ◽

Daisuke Yamashita ◽

Kohji Suzuki ◽

Masafumi Noda

Keyword(s):

Fine Structure ◽

High Temperature ◽

Magnesium Alloy ◽

Grain Boundary ◽

Room Temperature ◽

Grain Boundary Sliding ◽

Az31 Magnesium Alloy ◽

Temperature Deformation ◽

Alloy Plate ◽

Boundary Sliding

Abstract. This study examined the critical plastic formability limit of a fine-structure AZ31 magnesium alloy plate under warm and high temperature based on the strength of a magnesium alloy that has cavities at room temperature. The cyclic hot free-forging process as pre-form working following rolling at a light reduction ratio fabricated a fine-structure AZ31 magnesium alloy plate. The appearance of the cavities was examined in detail together with changes in the structure and preparation methods before further damage at high temperatures with increasing uni-and biaxial plastic deformation. The allowable deformation limit in the super plasticity process can be estimated from the strength of the deformed material and forming limit diagram (FLD) at room temperature. During high-temperature deformation, cavities are produced by stress concentrations at grain boundary triple points and striation bands due to grain boundary sliding. The cavitations growth behavior is dependent upon deformation conditions, and a high percentage of large cavities occupy the sample surface as a large amount of grain boundary sliding is present, i.e., as uniform elongation grows larger, the cavity size also increases. In a case where 200% uniaxial strain was applied to a fine-grained structure material at a temperature of 623K under a strain rate of 10-4s-1, the tensile strength at room temperature decreased about 13%, and elongation was 10% less, compared with that of a material to which no load was applied due to the influence of cavities. In a case of biaxial deformation, the values were 28% lower. It is possible to draw a FLD based on the cavity incidence fraction .

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