Fatigue crack growth behaviour in molten-metal processed SiC particle-reinforced aluminium alloys

Shinji Kumai*, Julia E. King, John F. Knott

*Corresponding author for this work

    Research output: Contribution to journalArticle

    Abstract

    Fatigue crack initiation and subsequent short crack growth behaviour of 2014-5wt%SiC aluminium alloy composites has been examined in 4-point bend loading using smooth bar specimens. The growth rates of long fatigue cracks have also been measured at different stress ratios using pre-cracked specimens. The distributions of SiC particles and of coarse constituent particles in the matrix (which arise as a result of the molten-metal processing and relatively slow cooling rate) have been investigated. Preferential crack initiation sites were found to be SiC-matrix interfaces, SiC particles associated with constituent particles and the coarse constituent particles themselves. For microstructurally short cracks the dispersed SiC particles also act as temporary crack arresters. In the long crack growth tests, higher fatigue crack growth rates were obtained than for monolithic alloys. This effect is attributed to the contribution of void formation, due to the decohesion of SiC particles, to the fatigue crack growth process in the composite. Above crack depths of about 200 μm 'short' crack growth rates were in good agreement with the long crack data, showing a Pris exponent, m = 4 in both cases. For the long crack and short crack growth tests little effect of specimen orientation and grain size was observed on fatigue crack growth rates, but, specimen orientation affected the toughness. No effect of stress ratio in the range R = 0.2-0.5 was seen for long crack data in the Paris region.
    Original languageEnglish
    Pages (from-to)1-11
    Number of pages11
    JournalFatigue and Fracture of Engineering Materials and Structures
    Volume15
    Issue number1
    DOIs
    Publication statusPublished - Jan 1992

    Fingerprint

    Fatigue crack propagation
    Liquid metals
    Aluminum alloys
    Cracks
    Crack propagation
    Crack initiation
    Composite materials
    Toughness
    Cooling
    Processing

    Keywords

    • aluminum and alloys
    • metals testing fatigue
    • silicon carbide
    • crack initiation
    • stress ratio
    • void formation
    • composite materials

    Cite this

    @article{0171c659d21d4cdfab9f022520a761fc,
    title = "Fatigue crack growth behaviour in molten-metal processed SiC particle-reinforced aluminium alloys",
    abstract = "Fatigue crack initiation and subsequent short crack growth behaviour of 2014-5wt{\%}SiC aluminium alloy composites has been examined in 4-point bend loading using smooth bar specimens. The growth rates of long fatigue cracks have also been measured at different stress ratios using pre-cracked specimens. The distributions of SiC particles and of coarse constituent particles in the matrix (which arise as a result of the molten-metal processing and relatively slow cooling rate) have been investigated. Preferential crack initiation sites were found to be SiC-matrix interfaces, SiC particles associated with constituent particles and the coarse constituent particles themselves. For microstructurally short cracks the dispersed SiC particles also act as temporary crack arresters. In the long crack growth tests, higher fatigue crack growth rates were obtained than for monolithic alloys. This effect is attributed to the contribution of void formation, due to the decohesion of SiC particles, to the fatigue crack growth process in the composite. Above crack depths of about 200 μm 'short' crack growth rates were in good agreement with the long crack data, showing a Pris exponent, m = 4 in both cases. For the long crack and short crack growth tests little effect of specimen orientation and grain size was observed on fatigue crack growth rates, but, specimen orientation affected the toughness. No effect of stress ratio in the range R = 0.2-0.5 was seen for long crack data in the Paris region.",
    keywords = "aluminum and alloys, metals testing fatigue, silicon carbide, crack initiation, stress ratio, void formation, composite materials",
    author = "Shinji Kumai and King, {Julia E.} and Knott, {John F.}",
    year = "1992",
    month = "1",
    doi = "10.1111/j.1460-2695.1992.tb00011.x",
    language = "English",
    volume = "15",
    pages = "1--11",
    journal = "Fatigue and Fracture of Engineering Materials and Structures",
    issn = "8756-758X",
    publisher = "Wiley-Blackwell",
    number = "1",

    }

    Fatigue crack growth behaviour in molten-metal processed SiC particle-reinforced aluminium alloys. / Kumai, Shinji; King, Julia E.; Knott, John F.

    In: Fatigue and Fracture of Engineering Materials and Structures, Vol. 15, No. 1, 01.1992, p. 1-11.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Fatigue crack growth behaviour in molten-metal processed SiC particle-reinforced aluminium alloys

    AU - Kumai, Shinji

    AU - King, Julia E.

    AU - Knott, John F.

    PY - 1992/1

    Y1 - 1992/1

    N2 - Fatigue crack initiation and subsequent short crack growth behaviour of 2014-5wt%SiC aluminium alloy composites has been examined in 4-point bend loading using smooth bar specimens. The growth rates of long fatigue cracks have also been measured at different stress ratios using pre-cracked specimens. The distributions of SiC particles and of coarse constituent particles in the matrix (which arise as a result of the molten-metal processing and relatively slow cooling rate) have been investigated. Preferential crack initiation sites were found to be SiC-matrix interfaces, SiC particles associated with constituent particles and the coarse constituent particles themselves. For microstructurally short cracks the dispersed SiC particles also act as temporary crack arresters. In the long crack growth tests, higher fatigue crack growth rates were obtained than for monolithic alloys. This effect is attributed to the contribution of void formation, due to the decohesion of SiC particles, to the fatigue crack growth process in the composite. Above crack depths of about 200 μm 'short' crack growth rates were in good agreement with the long crack data, showing a Pris exponent, m = 4 in both cases. For the long crack and short crack growth tests little effect of specimen orientation and grain size was observed on fatigue crack growth rates, but, specimen orientation affected the toughness. No effect of stress ratio in the range R = 0.2-0.5 was seen for long crack data in the Paris region.

    AB - Fatigue crack initiation and subsequent short crack growth behaviour of 2014-5wt%SiC aluminium alloy composites has been examined in 4-point bend loading using smooth bar specimens. The growth rates of long fatigue cracks have also been measured at different stress ratios using pre-cracked specimens. The distributions of SiC particles and of coarse constituent particles in the matrix (which arise as a result of the molten-metal processing and relatively slow cooling rate) have been investigated. Preferential crack initiation sites were found to be SiC-matrix interfaces, SiC particles associated with constituent particles and the coarse constituent particles themselves. For microstructurally short cracks the dispersed SiC particles also act as temporary crack arresters. In the long crack growth tests, higher fatigue crack growth rates were obtained than for monolithic alloys. This effect is attributed to the contribution of void formation, due to the decohesion of SiC particles, to the fatigue crack growth process in the composite. Above crack depths of about 200 μm 'short' crack growth rates were in good agreement with the long crack data, showing a Pris exponent, m = 4 in both cases. For the long crack and short crack growth tests little effect of specimen orientation and grain size was observed on fatigue crack growth rates, but, specimen orientation affected the toughness. No effect of stress ratio in the range R = 0.2-0.5 was seen for long crack data in the Paris region.

    KW - aluminum and alloys

    KW - metals testing fatigue

    KW - silicon carbide

    KW - crack initiation

    KW - stress ratio

    KW - void formation

    KW - composite materials

    UR - http://www.scopus.com/inward/record.url?scp=0026626959&partnerID=8YFLogxK

    UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1460-2695.1992.tb00011.x/abstract

    U2 - 10.1111/j.1460-2695.1992.tb00011.x

    DO - 10.1111/j.1460-2695.1992.tb00011.x

    M3 - Article

    VL - 15

    SP - 1

    EP - 11

    JO - Fatigue and Fracture of Engineering Materials and Structures

    JF - Fatigue and Fracture of Engineering Materials and Structures

    SN - 8756-758X

    IS - 1

    ER -