Hydrogen Permeation and Trapping Characteristics of Cold-Drawn Pure Iron and Eutectoid Steel Evaluated by Thermal Desorption Spectrometry

摘要

Hydrogen absorption characteristics of pure iron and eutectoid steel cold-drawn andannealed have been evaluated by Thermal Desorption Spectrometry (TDS). The pure ironspecimens whose structure is ferrite (α), and eutectoid steel specimens whose structure is cr/Fe_3Clamellae, are produced under various degree of reduction area and under various heat treatmentconditions. These specimens absorbed hydrogen in 20 mass % NH_4SCN solution were measuredusing TDS. TDS analysis shows that the hydrogen desorption of pure iron has a single peak, whilethat of eutectoid steel has two peaks. The lower-temperature peak corresponds to hydrogendesorbed from trapping sites of point defects, of clusters, and of dislocations. Thehigher-temperature peak corresponds to hydrogen desorbed from trapping sites of interfacedislocations between the a and Fe_3C, and/or of point defects and of dislocations in Fe_3C.