Evolution of material properties during physical aging

Gregory B. McKenna, Yves Leterrier, Carl R. Schultheisz

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


Aging experiments using the NIST torsional dilatometer have been performed in which the temperature of an isothermally equilibrated epoxy glass was abruptly changed to a new temperature T0 and the evolution of the volume and torsional relaxation responses recorded. The results of down-jump and up-jump experiments were found to differ dramatically. Not only is the normal asymmetry of volume approach to equilibrium found, but the mechanical responses are found to evolve differently from the volume response, contrary to simple free volume models of the physical aging process. It is found that the torsional modulus changes with increasing time after the T-jump. In the case of the down-jump the evolution of the modulus ceases prior to that of the volume of the sample. In the up-jump experiment, the contrary is true, viz., the modulus continues to evolve after the volume has attained its equilibrium value. The implications of this for the description of material behavior are discussed.

Original languageEnglish
Title of host publicationUse of Plastics and Plastic Composites
Subtitle of host publicationMaterials and Mechanics Issues
EditorsM. Ramulu, R. Komanduri
PublisherPubl by ASME
Number of pages16
ISBN (Print)0791812529
StatePublished - 1993
EventProceedings of the 1993 ASME Winter Annual Meeting - New Orleans, LA, USA
Duration: Nov 28 1993Dec 3 1993

Publication series

NameAmerican Society of Mechanical Engineers, Materials Division (Publication) MD


ConferenceProceedings of the 1993 ASME Winter Annual Meeting
CityNew Orleans, LA, USA


Dive into the research topics of 'Evolution of material properties during physical aging'. Together they form a unique fingerprint.

Cite this