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In FCC crystals the a/2* unit dislocations can dissociate to produce a ribbon of stacking fault. Which among the following is as an example of the same? ->a/6* + a/6 b) a/2*->a/6* + a/6 c) a/2*->a/6* + a/6 d) a/2*->a/6* + a/6

In FCC crystals the a/2* unit dislocations can dissociate to produce a ribbon of stacking fault. Which among the following is as an example of the same? ->a/6* + a/6 b) a/2*->a/6* + a/6 c) a/2*->a/6* + a/6 d) a/2*->a/6* + a/6 Correct Answer unit dislocations can dissociate to produce a ribbon of stacking fault. Which among the following is as an example of the same? ] a/2*->a/6* + a/6

a/2*->a/6* + a/6* is an example and this gives a stacking fault on (111) separated by two Shockley partials. Since the stacking fault is in effect four close-packed layers of hcp crystal, it can act as a very potent nucleation site for an hcp precipitate.

Related Questions

The higher the width of the stacking fault _________ will be the stacking-fault energy. Higher the stacking fault energy __________ will be the cross slip.
A metal crystallizes into two cubic phases BCC and FCC. The ratio of densities of FCC and BCC is equal to 1.5. Calculate the difference between the unit cell lengths of the FCC and BCC crystals if the edge length of the FCC crystal is equal to 4.0 Å.
Stainless steel A has a stacking fault energy of 8 mJ.m-2 and stainless steel B has a stacking fault energy of 45 mJ. m-2. The correct statement out of the following are.
P. A will have a wider stacking faults than B
Q. A will strain harden more rapidly than B
R. A and B will develop similar type of substructure
S. A and B will have the same temperature dependence of flow stress.
The stacking fault in FCC will create a thin region of ___________ in stacking of the FCC.
The _______ the stacking-fault energy, the higher the separation between the partial dislocations and the ________ the stacking fault.
Which of the following statements are true about edge dislocations?
P. Edge dislocations do not have an extra half plane associated with them.
Q. The Burger vectors is perpendicular to the direction.
R. Edge dislocations can avoid obstacles by cross-slip.
S. Depending on geometry, parallel edge dislocations of opposite signs can attract or repel one another.
In a village 50% of the villagers produce rice, 40% of the villagers produce apples and 50% of the villagers produce vegetables, 20% of the villagers produce rice and apples both, 25% of the villagers produce apples and vegetables both, 20% of the villagers produce rice and vegetables both and 10% of the villagers produce all three. Find the percentage of villagers who do not produce anything.
The material with higher stacking fault energy has higher fatigue strength whereas the material with lower stacking fault will have a lower fatigue limit.
The effect of grain size on the fatigue strength is predominant in material with high stacking fault energy while the effect of grain size is negligible in low stacking fault energy material.
The material with low stacking fault energy is prone to sub-grain formation compared to the metal with high stacking fault energy.