Accurate Measurement of Hydrogen in Steel

Senadheera, Thushanthi D.A.A.

Accurate Measurement of Hydrogen in Steel

atmire.migration.oldid	856
dc.contributor.advisor	Shaw, W. J. D.
dc.contributor.author	Senadheera, Thushanthi D.A.A.
dc.date.accessioned	2013-04-29T15:09:59Z
dc.date.available	2015-04-30T07:00:25Z
dc.date.issued	2013-04-29
dc.date.submitted	2013	en
dc.description.abstract	Accurate measurement of hydrogen in steels is one of the greatest challenges in the field of applied science. Even though research on hydrogen in steels has been carried out over the last ten decades, very little progress has been made in fundamental areas because of the lack of a reliable method for measuring hydrogen within a steel. The hydrogen atom's small size and its one atomic orbit have caused di culties in applying readily established measuring techniques to measure the simplest atom. The small size of the hydrogen atom has also made leak proofing the hydrogen measuring systems extremely difficult; thus, most apparatus are vulnerable to leaking. Additionally, the need to measure extremely small quantities and the high degree of statistical variation in the measured quantities have made the measured hydrogen quantities uncertain. The main task of this research study was to design and construct a new, direct hydrogen measuring device called the Temperature Vacuum Hydrogen System (TVHS) and to explore some higher temperature measurements of hydrogen in steel using this new device. This thesis provides a study of the direct hydrogen measuring methods available, the improvements implemented on the standard eudiometer method to improve the method's accuracy and the users' safety, a discussion of the problems faced during the construction and operation of the TVHS, and the solutions applied to mitigate them. The hydrogen volumes measured using the TVHS at 50, 150, 250, and 350 C in hydrogen charged AISI 1020 steel samples; and temperature-time relationships for measured hydrogen quantities; an equation to correlate the measured amounts from the TVHS method with the amounts measured using the standard eudiometer method are also provided in this thesis. Key findings of the tests carried out using the TVHS were that a significantly higher amount of hydrogen egressed at 350 C compared to the amounts that egressed at lower test temperatures and the time durations took longer than expected for stabilizing the egressed hydrogen amounts. Equations to predict hydrogen amounts egress from steel samples that are charged with low hydrogen concentrations were also derived. In addition, a chemical analysis on a steel sample immersed in mercury at low-elevated temperatures for an extended period showed a possibility for hot mercury to dissolute carbon from the pearlite structure of the steel, leaving the iron in the structure.	en_US
dc.description.embargoterms	2 years	en_US
dc.identifier.citation	Senadheera, T. D. (2013). Accurate Measurement of Hydrogen in Steel (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/24654	en_US
dc.identifier.doi	http://dx.doi.org/10.11575/PRISM/24654
dc.identifier.uri	http://hdl.handle.net/11023/629
dc.language.iso	eng
dc.publisher.faculty	Graduate Studies
dc.publisher.institution	University of Calgary	en
dc.publisher.place	Calgary	en
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subject	Materials Science
dc.subject.classification	Hydrogen	en_US
dc.subject.classification	measurement	en_US
dc.subject.classification	hot-extraction	en_US
dc.subject.classification	Mercury	en_US
dc.subject.classification	eudiometer	en_US
dc.title	Accurate Measurement of Hydrogen in Steel
dc.type	doctoral thesis
thesis.degree.discipline	Mechanical and Manufacturing Engineering
thesis.degree.grantor	University of Calgary
thesis.degree.name	Doctor of Philosophy (PhD)
ucalgary.item.requestcopy	true