ISSN:
1460-2695
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract— The influence of Al2O3 particle reinforcement on the fatigue crack growth properties of 6061-T6 aluminium alloy in the near threshold regime has been investigated at a load ratio of R=– 1 using an alloy with 15 vol.% fine particles (6061/Al2O3/15p) and one with 21 vol.% coarser particles (6061/Al2O3/21p). The Al2O3 particles act as obstacles for fatigue crack growth and are especially effective at very low cyclic loads. For the reinforced alloy with fine particles the threshold of the stress intensity amplitude is higher than that for the alloy containing coarse particles, and the lowest threshold value of Kmax was obtained for pure 6061-T6. Fracture of ceramic particles and interfaces between matrix and Al2O3 particles, both more frequent for coarser particles, may serve as an explanation for the more effective improvement of fatigue crack growth properties by fine particles. At maximum stress intensity factors above 6.5 MPa√m, fatigue crack growth in the particle reinforced alloys is faster than in the unreinforced alloy 6061-T6, which is attributed to more frequent particle and interface fracturing.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1460-2695.1995.tb01190.x
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