Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites

A. Goel, K. K. Chawla, U. K. Vaidya, Nikhilesh Chawla

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Long fiber reinforced thermoplastic (LFT) composites are finding increasing use in structural applications. An understanding of the fatigue behavior of LFT is of considerable importance since the structural parts made from LFT are subjected to cyclic loading conditions. In the present work, we studied the fatigue behavior in terms of stress (S) - Number of cycles to failure (N) of LFT (20 vol. % E-glass fiber/polypropylene), made by extrusion-compression molding process. We report the results of the effect of frequency and the effect of processing induced preferential fiber orientation on the fatigue life of LFT. Fatigue tests were conducted at 10, 15 and 20 Hz. The R-ratio was kept constant at 0.2. Fatigue life decreased with an increase in frequency. This result was attributed to the hysteretic heating phenomenon taking place in the composite at higher frequency. Such heating can cause the polypropylene matrix to soften and reduce its capacity to transfer load to the reinforcing fiber causing premature failure of the composite. Preferential orientation of long fibers also develops in the LFT during processing. Fatigue life of samples tested along longitudinal direction showed a higher fatigue life than the transverse samples. This was a direct result of the contribution of better load transfer to long fibers in the longitudinal direction.

Original languageEnglish (US)
Title of host publicationInternational SAMPE Symposium and Exhibition (Proceedings)
Volume52
StatePublished - 2007
EventSAMPE '07: M and P - From Coast to Coast and Around the World - Baltimore, MD, United States
Duration: Jun 3 2007Jun 7 2007

Other

OtherSAMPE '07: M and P - From Coast to Coast and Around the World
CountryUnited States
CityBaltimore, MD
Period6/3/076/7/07

Fingerprint

Thermoplastics
Fatigue of materials
Fibers
Composite materials
Polypropylenes
Extrusion molding
Heating
Compression molding
Fiber reinforced materials
Processing
Glass fibers

Keywords

  • Fatigue
  • Thermoplastic

ASJC Scopus subject areas

  • Building and Construction
  • Chemical Engineering(all)
  • Polymers and Plastics
  • Chemical Engineering (miscellaneous)

Cite this

Goel, A., Chawla, K. K., Vaidya, U. K., & Chawla, N. (2007). Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites. In International SAMPE Symposium and Exhibition (Proceedings) (Vol. 52)

Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites. / Goel, A.; Chawla, K. K.; Vaidya, U. K.; Chawla, Nikhilesh.

International SAMPE Symposium and Exhibition (Proceedings). Vol. 52 2007.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Goel, A, Chawla, KK, Vaidya, UK & Chawla, N 2007, Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites. in International SAMPE Symposium and Exhibition (Proceedings). vol. 52, SAMPE '07: M and P - From Coast to Coast and Around the World, Baltimore, MD, United States, 6/3/07.
Goel A, Chawla KK, Vaidya UK, Chawla N. Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites. In International SAMPE Symposium and Exhibition (Proceedings). Vol. 52. 2007
Goel, A. ; Chawla, K. K. ; Vaidya, U. K. ; Chawla, Nikhilesh. / Fatigue behavior of long fiber reinforced thermoplastic (LFT) composites. International SAMPE Symposium and Exhibition (Proceedings). Vol. 52 2007.
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