This study presents an experimental study of the effect of quenching temperature from the inter-critical
region (α+γ region) on the fatigue life of AISI 1010 plain low-carbon steel. In this study identical test specimens of
the AISI 1010 were heat-treated by oil quenching followed by tempering, specimens were heat-treated at different
quenching temperatures between 750°C to 850°C and followed by tempering at 550°C. The specimens were then tested to compare their fatigue life at constant stress amplitude; the standard high speed rotating beam test was adapted for this purpose. It was found that there is a direct relation between quenching temperature from the intercritical region and fatigue life; the fatigue life can be increased up to 625% by increasing the quenching temperature to 850°C. This finding is important as it enhances much the ability of the AISI 1010 steel to resist fatigue failure.