The titanium gold plating process of aluminum profiles belongs to the coating technology, which is to add the pre plating and electroplating process steps on the basis of the conventional titanium plating process. The aluminum profile process is to place the activated plated parts in the aqueous solution of salt and hydrochloric acid for chemical treatment; The plating solution of the electroplating process includes nickel sulfate, nickel chloride, boric acid, sodium dodecyl sulfate, saccharin and brightener. This process has the advantages of simplicity, practicality and good effect. The film hardness of the titanium gold aluminum profile produced by this process is HV ≈ 1500, and it is 150 times more wear-resistant than the 22K gold plating under the same conditions. It can be processed into a variety of bright series of aluminum profile products such as gold, color and black in various forms.

Extrusion defect. During the extrusion process of aluminum profiles, due to whether the extrusion equipment is complete, whether the extrusion process is mature and whether the operation is improper, defects such as bubbles, inclusions, layering, color difference and distortion will occur, which will affect the quality of aluminum profiles.

The thickness of the oxide film is thin. The national standard stipulates that the thickness of oxide film of building aluminum profile shall not be less than 10um (μ m). The thickness is not enough, and the surface of aluminum profile is easy to rust and corrode. The thickness of oxide film of some aluminum profiles without product name, factory address, production license and qualification certificate in the sampling inspection is only 2 to 4um, and some even have no oxide film. According to experts' estimation, the cost of power consumption per ton of profile can be reduced by more than 150 yuan per 1 um of oxide film thickness.

The chemical composition is unqualified. The aluminum profile mixed with a large amount of mixed aluminum and waste aluminum can greatly reduce the cost, but it will lead to unqualified chemical composition of building aluminum profiles and seriously endanger the safety of construction projects.

Reduce the profile wall thickness. The wall thickness Z of 90 series sliding window is not less than 1.4mm according to the national standard, and some products are only 0.6 to 0.7mm. 46 series ground spring door type, the wall thickness Z of the aluminum profile used in the national standard is not less than 1.62mm, and some products are only 0.97 to 1.18mm in the sampling inspection.

The low-quality aluminum profiles greatly reduce the closing time, reduce the loss of chemical reagents, and reduce the cost, but the corrosion resistance of the profiles is also greatly reduced.

How is the aluminum corrosion-resistant treatment done. First of all, DC power supply or DC and AC superimposed power supply are adopted. There are many kinds of solutions, and sulfuric acid hard anodizing treatment is more common. When sulfuric acid hard anodizing method is adopted, various factors affecting the hard anodized film layer shall be considered.

(1) Initial voltage and treatment time: the initial voltage and time of hard anodizing treatment also have a great impact on the quality of the oxide film. If the initial voltage is too high, the current will increase, the Joule heat and the heat of formation will increase sharply, and the dissolution speed will increase sharply. The oxide film is soft, matte, powdered and not wear-resistant.

Initial voltage and treatment time: the initial voltage and time of hard anodizing treatment also have a great impact on the quality of the oxide film. If the initial voltage is too high, the current will increase, the Joule heat and the heat of formation will increase sharply, and the dissolution speed will increase sharply. The oxide film is soft, matte, powdered and not wear-resistant.

(2) Water: water is the main component of hard anodizing treatment. Generally, distilled water or cold boiled water is used instead of tap water, because tap water contains chloride ions. When Cl - & gt; 1%, the parts will corrode and appear white spots in the oxidation process.

(3) The concentration of sulfuric acid oxidation treatment is usually 200-250 g / L, and the relative density of the tank solution (at room temperature) is 1.12-1.15.

(4) Stirring of aluminum hard oxidation solution: the stirring speed is related to the formation speed of oxide film (oxide film quality).

(5) Temperature of aluminum hard oxidation treatment: temperature is one of the important factors affecting the quality of oxide film. The temperature of anodic oxidation is strictly controlled, the hard oxide film is thickened, the hardness is increased, and the film is smooth and dense.

(6) For the oxidation treatment time: generally, the thickness of the oxide film increases with the extension of the oxidation treatment time, but after a certain time, if the applied voltage is not increased, the oxide film actually does not increase. If the time is prolonged continuously, the hardness of the oxide film is low, and the oxide film is loose and powdered. On the contrary, the oxidation treatment time is too short, and the thickness of the oxide film is thin and not wear-resistant.

(7) Current density: current is also one of the important factors affecting the quality of oxide film, which has a great relationship with the formation speed of oxide film and the structure of oxide film. When the current density is too low, the formation speed of oxide film is slow and the treatment time increases; On the contrary, if it is too high, the solution and electrode will overheat due to Joule effect. The dissolution speed of the oxide film increases, the hardness decreases, and the surface is rough, loose and powdered.

Source: Changjiang nonferrous metals network