KKKKI T OK ANNKAI.IM;. 



Tin- effects of previous loading on test bars may, 

 therefore, be summed up as follows : 



(a) If the bar is strained beyond the yield point, 

 and the load removed, a second loading will be 

 accompanied by a higher yield point than before, 

 and similarly for every repetition. 



(b) In the case of steel, if the bar is annealed after 

 the overstraining, the yield point will be approxi- 

 mately the same as in the original state. 



(c) Cold rolling and wire drawing, without annealing, 

 raise the yield point, increase the ultimate strength, 

 and lower the ductility. 



(d) Annealing restores the metal approximately to its 

 original state. 



(e) The effect of a long-continued load beyond the 

 yield point is to increase the ultimate strength 

 and diminish the ductility. 



