摘要 |
The apparatus and method for processing steel strand wire cable and the like for use in prestressed concrete is disclosed in which the outer surface of the cable produced has a substantial pure rust or hydrated oxide coating thereon enabling the cable to be utilized immediately in concrete configurations to thereby produce substantially higher flexural strengths in prestressed concrete than heretofore in the prior art. The apparatus and method specifically encompasses the use of ultrasonic cleaning equipment which causes cavitation cleaning effects in the liquid medium through which the cable passes during its cleaning process. In effect, the ultrasonic cleaning "catalyzes" the chemical redox reactions by removing all surface inhibitors and reducing reactant diffusion barriers thus accelerating surface wetting of the strand cable with H2O and O2, such that the rusting chemical reactions can occur spontaneously. The dominant bond developed between the steel and concrete is chemical. The bonding or wetting agent is ferro-orthosilicate, formed by the reaction of pure rust (FeO.Fe2O3) with silicates (SiO2) in the cement mixture used for making the concrete structure.
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