I-3 ASSESSMENT OF REDUCED PRESSURE TEST FOR HYDORGEN MEASUREMENT OF ALUMINUM CASTING(Session: Casting/Molding)

Reduced pressure test has long been used widely as a hydrogen measurement technique in aluminum foundries. Result in terms of hydrogen content obtained from this technique is, however, neither conclusive nor reliable enough. There are implications underlying the measured hydrogen level. In this study, a series of the reduced pressure test was conducted and values of hydrogen level of AlSi7 samples were subsequently evaluated employing quantitative density analysis. It is shown that, without proper practices in terms of casting conditions during the test, there exist significant discrepancies in the hydrogen measurement.