Surface treatment and sizing technique
The surface treatment of carbonized fibers is done by electrochemical oxidation process. The unit comprises of a system of 1) graphite rollers at the surface, which act as anode, 2) steel rollers submerged in the electrolyte solution and 3) cathodic carbon plates submerged in the electrolyte. A DC voltage is applied between the graphite rollers and the cathode plate, while the electrolyte is circulated in the bath. The traversing carbon fiber tows, in contact with anodic graphite roller, undergoes oxidation and gets micro etched at the surface. The surface treated fibers are washed in the adjacent water bath to avoid the carryover of electrolyte.
Tow width: 0.6 m
Surface treatment current: upto 20 A
Traverse length: upto 6 m
Temperature: Ambient temperature (typically 25oC)
Facilities where this technique is used : Fiber heat treatment facility (F3)
Major mile stones / results of this technique: Certification for standard modulus grade carbon fibers