화학공학소재연구정보센터
International Journal of Mineral Processing, Vol.74, No.1-4, 177-187, 2004
Aggregate liberation from concrete by flow cavitation
Short-time cavitation erosion was utilized to selectively liberate aggregate particles from concrete substrates. Five different concrete mixtures with compressive strengths between 23 and 80 MPa were subjected to erosion in a flow cavitation chamber. Cavitation erosion with an exposure time as low as 10 s generated measurable material removal. Erosion rate depended mainly on material texture (density), and showed only a weak dependence on fracture toughness and compressive strength. The erosion mode was intergranular in most cases, thus matrix and aggregate could be separated with separation efficiencies between 46% and 90%. A fracture mechanics model was developed to explain the selectivity effects in cavitation erosion. (C) 2003 Elsevier B.V. All rights reserved.