Abstract
The quenching of steel products is a heat-treatment technology that improves durability and fatigue strength. In order to control distortion and strain due to quenching, recently, a new technology of gas quenching such as nitrogen gas was developed in mobile car industry. We developed the gas cooling evaluation device that it was possible to be visible of a thermal flow around a specimen during gas quenching at the same time to measure cooling ability of gas to use for cooling. In this paper, the gas flow velocities have been measured in situ using a PIV method (laser imaging method) and compared to gas locations in the cylinders.
