Table 5.
The optimal duration times estimated for the heat treatment at 200℃ according to the values of × ×

× ×	Severity factor	Duration time (min.)
900	4.898	90
800	4.925	96
700	4.960	104
600	5.010	116
500	5.285	219
400	5.369	266
300	5.410	292
200	5.440	313
100	5.464	331