The Research Of Metallic Technology On Composite Mold

This paper studies the metallic technology of composite material mold which iselectroforming technology, and producing the new structural mold. It contains surfacemetal shell, the non-metallic enhanced layer by stratified manufacturing overleaf.This mold concentrates the metal mold's advantages of high precision, dimensionalstability, long life and the non-metallic mold's advantages of short manufacturingcycle, light weight, low-cost.Electroforming is a metal electrodepositing process, which uses metallic ornon-metallic objects as cathode, and electrodeposits metal on its surface, thenseparates electrodeposited metal layer from the objects and gets metal replication justas objects.In this paper, it is carried on for degreasing experiment firstly, and the studyshows that alkaline degreasing is the most effective method; In the electroformingprocess, the technology is studied for electroforming nickel and nickel and cobalt bytechnology parameters influencing the performance of the electroforming layer, andthe study shows that the optimal technology is as follows: the content of Co^2- reaches8 g·L^-1, PH (3.5～4.4), temperature(50℃), current density (6 A·dm^-2).Hardness ofelectroformed mold is HV570 and tensile strength 1487MPa using this technologyproduction. Mold has good corrosion resistance and high temperature resistance,thereby enhancing the use temperature and lifetime. In the electroforming Cuexperiment, it is studied for the main parameters influencing the inner stress, and theoptimum process parameters is as follows: the concentration of CuSO₄·5H₂O reaches200～240 g·L^-1,H₂SO₄(40～70 g·L^-1), Cl^-(80～100 mg·L^-1), MU(4～6 mL·L^-1),A(0.5～0.9 mL·L^-1), B(0.3～0.6 mL·L^-1),temperature(10～30℃) and the currentdensity(1.0～3.0A·dm^-2).In addition, the forming mechanism of inner stress makes apreliminary discussion.It is very considerable for waste water containing silver from laboratory, and ifit's abandoned, it is too wasteful and will pollute the environment, so recycling silverfrom silver-containing waste water, not only has a certain economic value, but also will be very important significance for saving raw materials and making full use ofthe resources. In this paper the method of chemical deposition - roasting is used torecycle silver, and the recycle rate of silver nitrate reaches to 78.67%.The analysis ofplasma atomic emission spectrometry and X-ray diffraction find that its purity (98%)and the content of impurity follow the reuse requests.Finally, the performance of the electroforming nickel layer accords with our userequirements using the optimum process parameters to electroform nickel in a modelship.