Stainless steel, titanium and titanium alloy electromechanical blackening solution

Abstract

The invention discloses stainless steel, titanium and titanium alloy electromechanical blackening solution, and belongs to the filed of surface treatment electromechanical conversion. The electromechanical blackening solution is suitable for forming a uniform, reliable-bonding and high corrosion resistance black electromechanical conversion film on the surface of stainless steel, titanium and titanium alloy. The electromechanical blackening solution is mainly technically characterized in that: the electromechanical blackening solution consists of the following components in volume concentration: 10 to 30g / L manganous nitrate, 20 to 30g / L potassium dichromate, 20 to 30g / L ammonium sulfate and 10 to 20g / L boric acid; and in the blackening process, the temperature of the blackening solution is controlled to between 10 and 40DEG C, and the direct current intensity is controlled to between 0.1 and 0.5A / dm2; various raw materials in a formula are all above electroplating grade; and the electromechanical blackening solution has the characteristics of simple components, quick and convenient preparation, good commonality, stable film bonding, high corrosion resistance of the film, long-term storage and the like.

Description

technical field [0001] The invention relates to an electrochemical blackening solution for stainless steel, titanium and titanium alloys, belonging to the field of surface treatment electrochemical conversion film, which is suitable for forming uniform, reliable bonding and high corrosion resistance black electrodes on the surface of stainless steel, titanium and titanium alloys. Chemical conversion coating layer. Background technique [0002] In the background technology, the surface of stainless steel parts is generally blackened by potassium dichromate or chromic anhydride plus concentrated sulfuric acid blackening solution or other commercially available blackening solutions. Titanium and titanium alloy parts generally use manganese sulfate as the main body. The black solution is blackened. However, it is difficult for stainless steel to form a true black film with the above-mentioned solution system, and the film is uneven and the bonding force is poor, and even some p...

AI Technical Summary

Problems solved by technology

However, it is difficult for stainless steel to form a true black film with the above solution system, and the film is uneven and the bonding force is poor, and even some published blackening solutions cannot form a black film at all.

The manganese sulfate system currently used in titanium and titanium alloy parts has problems such as poor film blackness, low solution stability, and complicated process operations.

At the same time, two different blackening solutions must be prepared when the surface of the above two kinds of substrate parts is blackened, and the two cannot be produced on the same line, which greatly increases the production workshop area and the complexity of production management.