creator Tong, Wei advisor Guralnick, Sidney Piezomagnetism designates a change in the magnetization of materials induced by mechanical actions such as tension or compression. The type of Barkhausen effect that occurs in this work consists of sudden, discontinuous jumps in a material’s magnetization that appear in response to smooth (continuous) stress variations. A series of strain controlled fatigue tests with an alternating sinusoidal waveform were carried out to study the relationship between the endurance limit and the Barkhausen effect. Results of fatigue tests on steel specimens exhibiting Barkhausen pulses at various stages are reported and a threshold-crossing analysis is applied to the test results. These studies show that when the fatigue limit is approached, the Barkhausen pulses become, in general, more intense in amplitude and quantity than at other stress levels. A hypothetical mechanism is proposed that relates the intensity of the Barkhausen response to the inception of micro-cracking and rearrangements of the mechanical lattice at the microscopic level. Submitted by Liana Khananashvili (khananashvili@iit.edu) on 2013-11-06T19:18:08Z No. of bitstreams: 2 PhDThesis052013.pdf: 19170230 bytes, checksum: 5ebef684f8b43554ff527dfffc43df5f (MD5) Signed Title Page.pdf: 108980 bytes, checksum: e9e6e72d13668e2f6dad5c3353366e32 (MD5) Made available in DSpace on 2013-11-06T19:18:08Z (GMT). No. of bitstreams: 2 PhDThesis052013.pdf: 19170230 bytes, checksum: 5ebef684f8b43554ff527dfffc43df5f (MD5) Signed Title Page.pdf: 108980 bytes, checksum: e9e6e72d13668e2f6dad5c3353366e32 (MD5) Previous issue date: 2013-05 PH.D in Civil Engineering, May 2013 2013 2013-05 http://hdl.handle.net/10560/3133 en Dissertation born digital application/pdf In Copyright http://rightsstatements.org/page/InC/1.0/ Restricted Access CAEE / Civil, Architectural, and Environmental Engineering Illinois Institute of Technology Affiliated department