___The Burger\'s vector of a screw dislocation is parallel to the dislocation li
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___The Burger's vector of a screw dislocation is parallel to the dislocation line. ___The Burger's vector of an edge dislocation is parallel to the dislocation line. ___The electron configuration for Ca^2+ is 1s^2 2s^2 2p^6 3s^2 3p^6. ___Covalence bonding is directional. ___Interstitial diffusion is normally more rapid than vacancy diffusion. ___Interstitial atom is not a point defect. ___The BCC and HCP structures are the closed packed structures. ___The diffusion coefficient for diffusion of C in BCC alpha iron is larger than that for diffusion of C in FCC gamma iron. The reason is that the diffusion of C in BCC alpha iron is interstitial diffusion while the diffusion of C in FCC gamma iron is vacancy diffusion.Explanation / Answer
1.True
Burger's vector of screw dislocation is parallel to the dislocation line.
2. False
In scew dislocation ,the Burger's vector and dislocation line are perpendicular to one another.
3.False
Configuration of Ca= 1s2,2s2 2p6,3s2 3p6,4s2
4.True
Covalent bonds being directional is that atoms bonded covalently prefer specific orientations in space relative to one another. Atoms which are bonded covalently have definite shape.
5.True
For vacancy diffusion to occur ,there has to be a hole for the atom or molecule to move into.Either one has to be open or diffusion thing has to wait for one to form.For interstitial diffusion, the diffusing species sort of slips through the void space in the lattice.
6.False.
Interstitial atoms is a interstitial defect.
7. False
BCC structure has neither a stacking sequence nor stacking faults .Therefore , it does not have a closed packed planes,while HCP has closed packed cubic crystal system.
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