Incorporation of gases in interstitial free steel

Gas desorption spectrometry has been used to investigate the composition of the gas and the quantities that are present in blowholes in interstitial free cold rolled steel. Besides monitoring of the gas release during ramp heating of selected parts containing blowholes, measurements have also been performed for in vacuo cutting of the blowholes at room temperature. The main component (>99%) of the gas is argon. Gas pressure in cavities with a volume of ∼ 0.1 mm 3 is a few bar. Some methane gas is also present, but the amount of hydrogen gas is negligible.