Metal Works Paper 2, May/June 2013  
Questions: 1 2 3 4 5 Main
General Comments
Question 4

(a)       State one reason for carrying out each of the following heat treatment  processes:

  1. tempering of cold chisel after hardening;
  2. annealing a metal after raising.

(b)       Explain how to harden and temper a cold chisel in a workshop.

(c)        List three hand forging operations.           

(d)       State one distinct feature that differentiates the hand file from the flat file.


This question was well attempted by the candidates with good performance. 
Part (b) of the question was the part that was poorly answered.  The required
response to part (b) of the question is:

-           it is heated to cherry red colour (750ºC)
-           it is quenched vertically in water or oil
-           it is reheated to purple colour (about 280º) and then cooled in oil to temper it.

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