Titanium alloying milling solution and milling technique used for the same

Abstract

The present invention discloses a titanium alloy chemical milling solution and its application milling process, which mainly contains nitric acid and hydrofluoric acid as the main components of mixed acid acidic corrosion solution, sodium lauryl sulfate, ethylene glycol n-butyl ether and / or or urea additives. The surface tension of the solution is maintained at a stable value by using the present invention. The adsorption of ethylene glycol n-butyl ether can reduce the interfacial tension and increase the chemical milling rate. Sodium lauryl sulfate, which improves the fluidity of the solution, can eliminate excessive corrosion of the metal at the root of the chemical milling fillet, and prevent the appearance of "grooves", "slopes" and "ripples". Sodium nitrate prevents the formation of scale of alloying elements on the surface of the chemical milling groove, improves the surface finish of the chemical milling surface and facilitates maintenance of the equipment. Urea can effectively absorb the nitrogen-containing gas produced in the chemical milling process, reduce the volatilization of acid liquid, and avoid pollution to the environment. The invention does not need heating equipment, the amount of hydrogen added is less than 9ppm, the service life of the solution is long, hydrogen embrittlement does not occur, and the process has little influence on the fatigue performance of the material.

Description

technical field [0001] The invention relates to a titanium alloy chemical milling solution and a chemical milling process using the chemical milling solution. Background technique [0002] Chemical milling is a precision micro-milling process especially suitable for parts with high dimensional accuracy and complex shapes. Chemical milling is a process of immersing metal blank parts in a chemical corrosion solution and using the corrosion of the solution to remove the surface metal. The chemical milling process in the prior art is: cleaning and degreasing the metal parts, coating the surface with a strippable protective coating that can resist the action of corrosive solutions, and engraving after curing at room temperature or high temperature. Peel off the protective coating applied to the parts that need to be processed by chemical milling, and then immerse the parts in the corrosion solution to corrode the exposed surface. The processing depth, rate and surface quality a...

AI Technical Summary

Problems solved by technology

The limitations of this process are: the root of the ribs cut out by chemical milling always has a rounded corner with a radius roughly equal to the depth of corrosion processing, which increases the waste weight of the parts; the finish of the chemical milling surface is worse than that of the raw material

[0006] The main disadvantage of the above-mentioned patents is that due to the lack of surfactant in the solution, the surface tension of the solution cannot be maintained at a stable value, which makes the fluidity of the solution poor, and "corrosion grooves", "slopes" and "slopes" are prone to appear after chemical milling. Corrugation" defect, the chemical milling rate in the same chemical milling area is not uniform, it is difficult to guarantee the depth accuracy of chemical milling

During the chemical milling process, yellow nitrogen-containing harmful gases that are discharged into the air are not conducive to environmental protection. The working temperature of the solution needs to be maintained between 44°C and 54°C, which will easily cause the acid to volatilize and pollute the air.