| In the world, the stainless steel cathode process, so-called ISA and KIDD Process in copper electrolytic refining has been a trend. However, there is not this technique with independent knowledge right in China. To fill in the blank of this technique, the stainless steel cathode sheet was prepared after many experiments in this thesis. This cathode sheet can substitute for the starter-sheet, which can eliminate the starter-sheet working procedure and omit stripping and processing facility of starter-sheet, shorten process flow and lower the cost and labor requirements. Meanwhile, the stainless steel cathode sheet can be re-used. Furthermore, the cathode sheet also can improve the cathode copper quality and increase the current efficiency. In the industrial application experiment, high quality cathode copper has been produced.The technological process from the stainless steel to the cathode sheet and the design of hanger bar, which is made use of hanger ing the sheet and conducting, were paid most attention. The aims to study are mainly included: (1) selection of stainless steel material, (2) manufacturing means of cathode sheet, (3)current efficiency study, (4) connecting means between the cathode sheet and the hanger bar, (5)anti-corrosion performance in the real electrolyte, (6)stripping performance research, (7) industrial application experiment approach, etc.A kind of austenite stainless steel was selected as the material of the cathode after the performance and the cost of stainless steel cathode sheet were analyzed, its contents being carbon 0. 091% by weight, nickel 8.866% by weight, chromium 18. 018% by weight, titanium 0. 836% by weight, iron 71. 001% by weight, and the rest is manganese, silicon, phosphorous and sulfur.The current efficiency was determined by many experiments, and the average current efficiency was 96.7%. Furthermore, the fluctuation of the current efficiency was quite small.The hanger bar and the connecting means between the cathode and the hanger bar was decided by the determination of the voltage reduction. The voltage determinationshowed, this means was superior to the ones abroad. The rectangle carbon steel waschosen to be the beam, which section is 20X20 millimeter. Copper cladding with2~3 millimeter thickness, was electroplated on the beam. This means has been examined in the real electrolytic refining in Yunnan Copper Corporation Limited. The results show that this means has good conducting performance, high intension and low cost.The anti -corrosion of cathode sheet, immerged into real electrolyte, was studied in the real electrolyte by means of weight-loss method and electrochemical method. The results indicate that two kinds of stainless steel both have good anti-corrosion performance. The selection in this paper has its feasibility because of low cost. Moreover, two kinds of surface treatment methods can improve the ability to resist local corrosion by increasing the pitting potential. The optimal process and conditions of chemical methods are: 30% nitric acid by concentration, room temperature and two hours. The electrolytic conditions are: at potential ISOOmv, 20minutes.Adhension strength was determined by way of stretching experiment. As a result, surface status has important influence on the adhension strength. In order to confirm the effect of various roughness, surface treatment methods and time, orthogonal methods were adopted to ensure the optimal process conditions. The results of orthogonal experiment demonstrate the primary and secondary factors: the chief one is surface roughness, the second is surface treatment means and the last is surface treatment time. As far as the single factor is concerned, the optimal level of surface roughness is burnished by sand paper, and its granularity is between 280# and 320#. The optimal level of surface treatment is electrolytic treatment, and the treatment time is 15 minutes. A calculating formula to obtain the force number of stripping machine at simulating a certain stripping means also given in...
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