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					  Slip
					Steel is malleable, meaning it can be drawn or 
					pressed into many different shapes without breaking. It is also 
					ductile, which means that it can be drawn into bars or even thin 
					wires without breaking. The concept of slip partially accounts for 
					this behavior. 
					
					 Picture 1  
					When steel bends, what actually happens is that layers of ions in the 
					steel are slipping over other layers and then forming attractions 
					with the ions now around them. This is why the steel bends without 
					breaking. See Picture 1.
					
					Dislocations
					The lattice structure naturally contains many 
					defects, that is, missing ions in layers. When a force is placed on 
					the steel, dislocations move through the lattice structure. Unlike 
					slip, only a relatively few number of ions need to move, not an 
					entire layer. See Picture 2. 
					
					Together, dislocation and slip account for malleability and 
					ductility of steel. 
		 
					 Picture 2  
					Grains 
					and dislocations Grain boundaries hinder the movement of dislocations. The more 
					grain boundaries that exist, the more difficult it is for 
					dislocations to move, and as a result, the steel is harder, 
					stronger, and stiffer.
					
					Coarse grained steel contains fewer grains and grain 
					boundaries than fine grained steel with many more grains and 
					boundaries. Because of this, fine-grained steel has 
					the potential to be stronger and more ductile than coarse grained 
					steel. 
					
					Often times, elements like vanadium are added to the 
					mixture of steel to provide nuclei around which grains can grow. 
					The objective of this process is to produce finer grained steel, and 
					vanadium is well known for its ability to assist in the control of 
					grain size. 
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