00:01
Okay, now we're going to explain the sources and implications of size effect in fracture mechanics.
00:05
So this refers to the phenomenon where mechanical behaviour and failure characteristics of material depend on their size dimensions.
00:13
Okay, particularly at micro -scrutinial level.
00:17
Okay, so let's firstly have a look at the size effects.
00:21
So we have statistical fluctuations.
00:25
Fluctuations.
00:29
So these are at the micro or nanoscale level where materials are composed of finite atoms or molecules.
00:36
And these fluctuations in the arrangement of particles can lead to size dependent variations in the material property.
00:43
We have surface energy to consider.
00:47
As the size of the material decreases, the proportion of atoms and molecules at the surface increases.
00:53
Increases to this higher surface area can result in increased energy affecting the overall mechanical behavior.
01:01
We have defects, so small sized material have a higher probability of containing defects or flaws that can influence their mechanical properties.
01:13
And four we have grain boundaries, so in polycrystalline materials the presence of grain boundaries become more significant significant small scales can affect the mechanical strength and fracture resistance...