Higher spectra approximations derived from multistep loading

Theocaris, PS

dc.contributor.author	Theocaris, PS	en
dc.date.accessioned	2014-03-01T01:05:27Z
dc.date.available	2014-03-01T01:05:27Z
dc.date.issued	1967	en
dc.identifier.issn	0303402X	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/8844
dc.subject	Degree of Approximation	en
dc.title	Higher spectra approximations derived from multistep loading	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/BF01520396	en
heal.identifier.secondary	http://dx.doi.org/10.1007/BF01520396	en
heal.publicationDate	1967	en
heal.abstract	A multistep loading programme for a cross-linked polymer with equidistant discontinuities jumping with constant amplitudes of stress or strain may yield higher approximations of the retardation or relaxation spectra to any degree of accuracy provided that the Boltzmann superposition principle is not violated. In the case of retardation spectra the multistep loading programme can be replaced by an initial creep loading followed by steps of recovery of equal amplitudes and time. In the case when an accurate composite curve of the material is available by application of the principle of reduced variables, this curve yields sufficient information for the tracing of retardation or relaxation spectra to any degree of approximation. Examples are given for the tracing of retardation and relaxation spectra up to their third approximation for an epoxy polymer and a polyurethane elastomer by using the multistep method. Three approximations of relaxation spectra for N.B.S. Polyisobutylene and Polymethylmethacrylate are also derived from their composite curves. © 1967 Dr. Dietrich Steinkopff Verlag.	en
heal.publisher	Steinkopff-Verlag	en
heal.journalName	Kolloid-Zeitschrift & Zeitschrift für Polymere	en
dc.identifier.doi	10.1007/BF01520396	en
dc.identifier.volume	215	en
dc.identifier.issue	2	en
dc.identifier.spage	149	en
dc.identifier.epage	157	en