Ws. Han et Yl. Bai, EMBRYO-DAMAGE INDUCED NUCLEATION OF MICROCRACKS IN AN ALUMINUM-ALLOY UNDER IMPACT LOADING, Acta metallurgica et materialia, 43(6), 1995, pp. 2157-2162
Citations number
7
Categorie Soggetti
Material Science","Metallurgy & Metallurigical Engineering
The nucleation of microdamage under dynamic loading was investigated t
hrough planar impact experiments accomplished with a light gas gun. Th
e microscopic observation of recovered and sectioned specimens showed
that microcracks were nucleated only by cracking of brittle particles
inside material. However, for comparison the in situ static tensile te
sts on the same material conducted with a scanning electron microscope
showed that the microcracks were nucleated by many forms those were f
racture of ductile matrix, debonding particles from matrix and crackin
g of brittle particles. The quantitative metallographic observations o
f the specimens subjected to impact loading showed that most of the cr
acked particles were situated on grain boundaries of the aluminium mat
rix. These facts suggested the concept of critical size and incubation
time of submicroscopic cavities in the dynamic case and the mechanism
of embryo-damage induced nucleation by fracture of brittle particles
in the aluminium alloy under impact loading was proposed.