Investigating the Effect of Cooling Media on Hardness, Toughness, Coefficient of Friction, and Wear Rate of Mild Steel Heat Treated at Different Temperatures

Figure 5

Coefficient of friction of sample cooled by oil, (a) heat treated by 500°C and sliding load 10 N, (b) heat treated by 500°C and sliding load 20 N, (c) heat treated by 900°C and sliding load 10 N, and (d) heat treated by 900°C and sliding load 20 N. (a–d) Present coefficient of friction of samples heat treated up to 500 and 900 degrees Celsius. (a) Reveals slow increase in coefficient of friction at 200 seconds. At the lower sliding force, which was 10 N, it was noticed that the maximum coefficient of friction is higher than the one of 20 N which was reported to be 0.530. (b) Shows faster coefficient increase at the start and slow increase after 100 seconds. Linear coefficient increase was noticed in (c), and the maximum coefficient of friction is 36 percent higher than that of a high sliding load. This implies that for samples cooled by oil, more force is required in order for sliding to occur at 10 N applied load.

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