Question 3
3. (a) (i) What is heat treatment?
(ii) Why is it necessary to heat-treat a metal?
(iii) List two quenching media.
(b) What is riveting?
(c) Sketch the following rivet heads:
(i) snap;
(ii) countersunk;
(iii) pan.
Observation
This question did not pose much problem to the candidates. Some of them interchanged the sketches of countersunk and pan rivet heads. The correct response is given below.
Pan
Countersunk