Jp. Tu et al., Slurry erosion-corrosion characteristics of squeeze cast aluminum alloy-aluminum borate composite, MATER CORRO, 50(4), 1999, pp. 205-212
The slurry erosion-corrosion behavior of 19.5 vol.% Al18B4O33 whisker reinf
orced AC4C Al composite in aqueous slurry containing 3.5 wt.% NaCl and 20 w
t.% silica has been investigated using a jet-in-slit rig. Erosion-corrosion
tests were performed with slurry having a jet velocity range 6.4 ms(-1) to
15.2 ms(-1) and at normal impact angle. The results indicated that the slu
rry erosion-corrosion characteristics were affected by the slurry velocity
and material properties. At low slurry velocities, as compared to the unrei
nforced alloy, the erosion-corrosion resistance of the composite was improv
ed because of increase in hardness as a result of whisker addition. However
, steady-state erosion-corrosion rate was found to increase with the additi
on of whisker to the matrix alloy at high slurry velocities. The erosion-co
rrosion rates of materials in the saline slurry were much higher than those
in the water slurry even though the corrosion components were very small.
It is found that the synergistic factor for the materials reduced with incr
easing slurry velocity although the synergism between erosion and corrosion
was greater at high slurry velocity. Localized corrosion occuring in the s
train-hardened layer caused a decrease in the fracture strain of composite
during erosion-corrosion. in the saline slurry, the material removal was en
hanced through cracking of flakes and detaching of whisker induced by stres
s and corrosion.