Chemical etching process precision tolerance affected by what factors

The chemical etching process is based on the original surface of the part as a reference, and is not like most of the machining methods, is a metal cutting machine tool datum to serve as a machining reference, and its machining deviation is only affected by the inherent machining accuracy of the machine tool. Therefore, chemical etching processing can be achieved by the processing tolerance is mainly affected by several factors.

1. The impact of the part material: the same material produced by different etching speed and effect, so that the same corrosion solution in the same will have different corrosion tolerances.

2. The impact of the size of the part: the larger the size of the part, in the corrosion tank in different locations, and thus the possibility of corrosion differences between the various parts of the greater, the main surface is the difference in etching speed.

3. The impact of the way the parts are hung: a large plate parts if it is vertically placed in the corrosion tank, after corrosion will appear under the thin on the back of the cone, so in the calculation of tolerances should also be this kind of corrosion process itself caused by the tolerance into the total tolerance.

4. The influence of the corrosive agent: must strictly control the concentration range of the chemical composition of the corrosive solution, to maintain the corrosive agent in the corrosion of all parts of the temperature distribution in the tank, to maintain the corrosive solution in the corrosion of all parts of the tank in the concentration of uniform.

5. The impact of the depth of corrosion processing: the deeper the depth of corrosion processing, the parts in the corrosion solution immersion time is longer, and the longer the time, the etching solution of various chemical composition of the change is also greater, and then make the etching speed and corrosion effect of the change increases.

6. Sample accuracy and graphic transfer accuracy of the impact: First, the sample plate used to delineate the graphics, the accuracy of this sample plate by the sample plate processing costs have a great impact. Second, for photographic and screen printing graphics transfer used in photographic film, photographic film can be very high precision, especially for photographic graphics transfer can be done and photographic film almost exactly the same graphics transfer precision.

7. The impact of the corrosion process. To ensure the accuracy of the corrosion level, must be experimentally determined by the side of the etching rate, and in this way to determine the precise size range of the graphic sample. Because of the effect of chemical etching changes in the horizontal direction, so used to process very accurate dimensions of the groove or convex rib are not desirable. Since machining with horizontal tolerance requirements in the range of ±0.25 mm - ±0.5 mm is widely used, especially in the aircraft industry, ships and other special industries in large numbers.