Correlation between fracture toughness and fatigue crack growth thresholds in RIM polyamide block copolymers filled with milled glass fibres

J. Karger-Kocsis, J. Daugaard, L. Amby

Research output: Contribution to journalArticle

Abstract

The fracture and fatigue behaviours of reaction injection moulded (RIM) polyamide block copolymers (NBC) without and with milled glass fibres (GF) were studied using the fracture mechanics concept at ambient temperature. The static fracture toughness determined according to the ASTM E 399 standard (KQ) aand its maximum value computed from the maximum load (KQ,max) decreased with increasing polyol (soft segment) content and proved to be unaffected by GF filling. Increasing the deformation rate, including high-speed impact bending tests, resulted in higher fracture toughness (Kd) values, closely matched to KQ,max. The resistance to fatigue crack propagation (FCP) deteriorated with increasing soft segment and GF filler content. This was explained by differences in the molecular build-up and porosity of the NBC and related composites caused by moulding. The lower and upper bounds of the stable FCP range were found at KQ and KQ,max, respectively.

Original languageEnglish
Pages (from-to)189-194
Number of pages6
JournalInternational Journal of Fatigue
Volume14
Issue number3
DOIs
Publication statusPublished - 1992

Fingerprint

Block Copolymers
Fracture Toughness
Fatigue Crack Growth
Nylons
Fatigue crack propagation
Polyamides
Glass fibers
Fatigue Crack Propagation
Block copolymers
Fracture toughness
Injection
Fiber
Molding
Polyols
Fracture Mechanics
Bending tests
Porosity
Fracture mechanics
Fatigue
Fillers

Keywords

  • failure
  • fatigue crack growth
  • fracture
  • fracture mechanics
  • glass fibre filler
  • Nyrim
  • polyamide-6 block copolymer
  • reaction injection moulding (RIM)
  • reinforced RIM

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials

Cite this

@article{8f354cd801f6434b8a222477394b4680,
title = "Correlation between fracture toughness and fatigue crack growth thresholds in RIM polyamide block copolymers filled with milled glass fibres",
abstract = "The fracture and fatigue behaviours of reaction injection moulded (RIM) polyamide block copolymers (NBC) without and with milled glass fibres (GF) were studied using the fracture mechanics concept at ambient temperature. The static fracture toughness determined according to the ASTM E 399 standard (KQ) aand its maximum value computed from the maximum load (KQ,max) decreased with increasing polyol (soft segment) content and proved to be unaffected by GF filling. Increasing the deformation rate, including high-speed impact bending tests, resulted in higher fracture toughness (Kd) values, closely matched to KQ,max. The resistance to fatigue crack propagation (FCP) deteriorated with increasing soft segment and GF filler content. This was explained by differences in the molecular build-up and porosity of the NBC and related composites caused by moulding. The lower and upper bounds of the stable FCP range were found at KQ and KQ,max, respectively.",
keywords = "failure, fatigue crack growth, fracture, fracture mechanics, glass fibre filler, Nyrim, polyamide-6 block copolymer, reaction injection moulding (RIM), reinforced RIM",
author = "J. Karger-Kocsis and J. Daugaard and L. Amby",
year = "1992",
doi = "10.1016/0142-1123(92)90373-K",
language = "English",
volume = "14",
pages = "189--194",
journal = "International Journal of Fatigue",
issn = "0142-1123",
publisher = "Elsevier Limited",
number = "3",

}

TY - JOUR

T1 - Correlation between fracture toughness and fatigue crack growth thresholds in RIM polyamide block copolymers filled with milled glass fibres

AU - Karger-Kocsis, J.

AU - Daugaard, J.

AU - Amby, L.

PY - 1992

Y1 - 1992

N2 - The fracture and fatigue behaviours of reaction injection moulded (RIM) polyamide block copolymers (NBC) without and with milled glass fibres (GF) were studied using the fracture mechanics concept at ambient temperature. The static fracture toughness determined according to the ASTM E 399 standard (KQ) aand its maximum value computed from the maximum load (KQ,max) decreased with increasing polyol (soft segment) content and proved to be unaffected by GF filling. Increasing the deformation rate, including high-speed impact bending tests, resulted in higher fracture toughness (Kd) values, closely matched to KQ,max. The resistance to fatigue crack propagation (FCP) deteriorated with increasing soft segment and GF filler content. This was explained by differences in the molecular build-up and porosity of the NBC and related composites caused by moulding. The lower and upper bounds of the stable FCP range were found at KQ and KQ,max, respectively.

AB - The fracture and fatigue behaviours of reaction injection moulded (RIM) polyamide block copolymers (NBC) without and with milled glass fibres (GF) were studied using the fracture mechanics concept at ambient temperature. The static fracture toughness determined according to the ASTM E 399 standard (KQ) aand its maximum value computed from the maximum load (KQ,max) decreased with increasing polyol (soft segment) content and proved to be unaffected by GF filling. Increasing the deformation rate, including high-speed impact bending tests, resulted in higher fracture toughness (Kd) values, closely matched to KQ,max. The resistance to fatigue crack propagation (FCP) deteriorated with increasing soft segment and GF filler content. This was explained by differences in the molecular build-up and porosity of the NBC and related composites caused by moulding. The lower and upper bounds of the stable FCP range were found at KQ and KQ,max, respectively.

KW - failure

KW - fatigue crack growth

KW - fracture

KW - fracture mechanics

KW - glass fibre filler

KW - Nyrim

KW - polyamide-6 block copolymer

KW - reaction injection moulding (RIM)

KW - reinforced RIM

UR - http://www.scopus.com/inward/record.url?scp=44049121908&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=44049121908&partnerID=8YFLogxK

U2 - 10.1016/0142-1123(92)90373-K

DO - 10.1016/0142-1123(92)90373-K

M3 - Article

AN - SCOPUS:44049121908

VL - 14

SP - 189

EP - 194

JO - International Journal of Fatigue

JF - International Journal of Fatigue

SN - 0142-1123

IS - 3

ER -