Effective Use of Weld Metal Hydrogen Trapping and Advance Diffusible Hydrogen Sensing

摘要

The development of an advance measuring apparati for diffusible hydrogen content based on electronic, optical and magnetic property measurements was investigated. The effort was to develop a rapid and accurate determination for both steel weld metal diffusible hydrogen content and its distribution. This investigation used the instrumentation acquired by the DURIP grant program. Thermoelectric (Seebeck) coefficient measurements are used to assess hydrogen content in higher strength low alloy steel, nickel-aluminum bronze, austenitic stainless steel, and hydrogen storage alloys. The thermoelectric power coefficient was also used to assess the soluble nitrogen content and nitride content in nitrogen strengthened structural steels. The role of hydrogen to assist high temperature forming (deformation) was investigated in ferrous and refractory alloys. The investigation sought a mechanistic understanding for the significant reduction of compressive stress to hot form hydrogen charged ferrous alloys and refractory alloys. Efforts were made to transfer the demonstrated effectiveness of weld metal hydrogen trapping, which results from investigation on rare earth additions to steel weld metal to lower the weld diffusible hydrogen content, to commercial welding practice and consumable products.