Combined effects of cooperative grain boundary sliding and migration and reinforced particles on crack growth in fine-grained Mg alloys

2018 ◽  
Vol 749 ◽  
pp. 705-714 ◽  
Author(s):  
Tengwu He ◽  
Miaolin Feng
Keyword(s):  
Grain Boundary ◽  
Crack Growth ◽  
Grain Boundary Sliding ◽  
Mg Alloys ◽  
Combined Effects ◽  
Fine Grained ◽  
Boundary Sliding ◽  
And Migration

Examination of Fracture Interfaces in Silicon Nitride

1975 ◽  
Vol 33 ◽  
pp. 60-61
Author(s):  
Nancy J. Tighe
Keyword(s):  
Silicon Nitride ◽  
Grain Boundary ◽  
Crack Growth ◽  
Subcritical Crack Growth ◽  
Slow Crack Growth ◽  
Ceramic Materials ◽  
Grain Boundary Sliding ◽  
Boundary Phase ◽  
Turbine Engines ◽  
Boundary Sliding

Silicon nitride is one of the ceramic materials being considered for the components in gas turbine engines which will be exposed to temperatures of 1000 to 1400°C. Test specimens from hot-pressed billets exhibit flexural strengths of approximately 50 MN/m2 at 1000°C. However, the strength degrades rapidly to less than 20 MN/m2 at 1400°C. The strength degradition is attributed to subcritical crack growth phenomena evidenced by a stress rate dependence of the flexural strength and the stress intensity factor. This phenomena is termed slow crack growth and is associated with the onset of plastic deformation at the crack tip. Lange attributed the subcritical crack growth tb a glassy silicate grain boundary phase which decreased in viscosity with increased temperature and permitted a form of grain boundary sliding to occur.

In-situ observation of cooperative grain boundary sliding and migration in the nano-twinned nanocrystalline-Au thin-films

2020 ◽  
Vol 180 ◽  
pp. 97-102 ◽  
Author(s):  
Qizhen Li ◽  
Lihua Wang ◽  
Jiao Teng ◽  
Xiaolu Pang ◽  
Xiaodong Han ◽  
...  
Keyword(s):  
Thin Films ◽  
Grain Boundary ◽  
Grain Boundary Sliding ◽  
In Situ Observation ◽  
Boundary Sliding ◽  
Au Thin Films ◽  
And Migration

Recrystallization and Grain Growth in Rocks and Minerals

2004 ◽  
Vol 467-470 ◽  
pp. 545-550 ◽  
Author(s):  
David J. Prior ◽  
Michel Bestmann ◽  
Angela Halfpenny ◽  
Elisabetta Mariani ◽  
Sandra Piazolo ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Grain Growth ◽  
Grain Boundary Sliding ◽  
Data Sets ◽  
Nucleation Process ◽  
Ebsd Data ◽  
Boundary Sliding ◽  
And Migration

Misorientation analysis, using EBSD data sets, has enabled us to constrain better recrystallization mechanisms in rocks and minerals. Observed microstructures are not explicable in terms of recovery, boundary bulging and migration alone. We have to invoke either a nucleation process (physics unknown) or grain rotations that are not related to grain or boundary crystallography. Such rotations can occur by diffusion accommodated grain boundary sliding and this mechanism explains best the microstructure and texture of recrystallized grains in some rocks.

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