Cold work dislocation (interactions)

[321GO]

Hi guys,

I know thtat cold working produces more dislocations that 'impede slip and thus increase strength' but i'm kind of puzzled to what exactly happens in the lattice.

In this context I also read about 'forest dislocations' but I'm srugling to get a clear comprehension on this, hope some of you could help, thanks in advance.

Is it that these 'new' dislocations act as a sort of 'step' or 'raised plateau' that impedes movement on the slipplane?

 

[metengr]

321GO;
Good questions. Here is a tip, there is plenty of good information on the internet that can be reviewed regarding dislocation interaction and slip systems of metals.

 

[FennLane]

Once Again - Dieter Mechanical Metallurgy.

Give good explanations of Frank Read Sources, Jogs, Climb, etc, etc.

To look at it more simply annealed steel would have around 10^8 dislocation lines per cm^2 of surface and a fully cold worked steel can have as many as 10^28 lines per cm^2. (This for the type of steel used for deep drawing)

Interactions between dislocations also means that in order for slip to occur the line tension of the dislocation has to increase and this is seen as work hardening.