Premium
Effect of frequency upon fatigue strength of a short glass fiber reinforced polyamide 6: A superposition method based on cyclic creep parameters
Author(s) -
Bernasconi Andrea,
Kulin Robb M.
Publication year - 2009
Publication title -
polymer composites
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.577
H-Index - 82
eISSN - 1548-0569
pISSN - 0272-8397
DOI - 10.1002/pc.20543
Subject(s) - materials science , creep , composite material , superposition principle , polyamide , cyclic stress , glass fiber , time–temperature superposition , stress (linguistics) , fiber , polymer , mathematics , mathematical analysis , linguistics , philosophy
The fatigue behavior of a conditioned short glass‐fiber reinforced polyamide 6 was studied and the effect of the cyclic frequency investigated. Load controlled fatigue tests were performed, and the strains and surface temperature of specimens were recorded continuously. The number of cycles to failure was found to be dependent upon cyclic creep rate, as is typical for short glass fiber reinforced polyamides in the conditioned state. A strong reduction of fatigue strength was observed for increasing cyclic load frequency. This was mainly related to the specimen temperature increase due to hysteretic self heating and its effect on the cyclic creep speed. A frequency superposition method is proposed, expressing the relationship between temperature rise, applied stress, and cyclic creep speed in terms of a parameter derived from the Larson–Miller steady creep parameter. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers