In part of a joint collaboration effort between Faraday Technology Inc., the UTINAM Institut (Besançon France), and the IRT M2P consortium in France we have been evaluating the potential of sono-electrochemical system within a state of the art REACH compliant trivalent hard chromium electrolyte. The need for a trivalent hard chromium electrolyte is based on the requirement of the industry to identify a suitable carcinogen free alternative to hard hexavalent chromium electroplating. Through our collaborative activity we have demonstrated the potential of this electrolyte to produce coatings with equivalent or superior: 1) plating rate, 2) Knoop hardness, 3) current efficiency, 4) adhesion, 5) corrosion resistance, 6) thickness, 7) Taber Abrasion, Ball on Flat Reciprocating and Dithering wear resistance, and with no hexavalent chromium formation in the bath. Moreover, ultrasound have proven to be an efficient process in improving penetrating capacity of the Cr coating into complex shapes. Furthermore, we have identified a potential process enhancement by utilizing sono in conjunction with pulse electrodeposition to improve wear index and achieve through into the recesses of type 1A1 embrittlement bars.

Acknowledgements: This study is supported by the US Army (W911NF-11-2-0014) and private sources, and by HCTC project