Common aluminum alloy die-casting 5 kinds of surface treatment methods

Common aluminum alloy die-casting 5 kinds of surface treatment methods

Many science and technology houses are interested in aluminum alloy die casting surface how to do smooth, frosted effect, aluminum alloy is how to make this radian surface, today by small edition to introduce the common aluminum alloy die casting 5 surface treatment methods.

Method 1: aluminum phosphorization

The effects of SEM, XRD, potential time curve, fluoride, Mn 2 +, Ni2 +, Zn 2 +, PO4, and membrane weight change. The study shows that guanidine nitrate is characterized by good water solubility, low dosage and rapid film formation, and is an effective promoter of aluminum phosphorization: fluoride can promote the film formation, increase the film weight, and refine the grain; Mn 2 +, Ni2 +, can obviously refine the grain, make the phosphating film uniform, compact and improve the appearance of the phosphating film; when Zn 2 + concentration is low, no film formation or film formation difference, with the increase of Zn 2 + concentration, membrane weight; the PO4 content greatly affects the phosphating film weight, and improve PO4. The content increases the phosphate membrane weight.

Method 2: alkaline electropolishing process of aluminum The alkaline polishing solution system was studied, and the influence of corrosion inhibitor and viscosity agent on the polishing effect was compared, the alkaline solution system with good polishing effect was successfully obtained, and the additives that can reduce the operating temperature, prolong the service life of the solution and improve the polishing effect for the first time. The experimental results show that adding appropriate additives to NaOH solution can produce good polishing effect. Exploratory experiments also found that the surface reflectivity of aluminum could reach 90% after using NaOH solution under some conditions, but due to the unstable factors in the experiment, further study is needed. The feasibility of polishing aluminum by DC pulse electropolishing under alkaline conditions is explored. The results show that the pulse electropolishing method can achieve the leveling effect of DC constant voltage electropolishing, but the leveling speed is slow.

3, aluminum and aluminum alloy environmentally friendly chemical polishing Determine the development of a new environmentally friendly chemical polishing technology based on phosphorosulfuric acid, which aims to achieve zero emission of NOx and overcome the quality defects of previous similar technologies. The key to the new technology is to add some compounds with special role to the base liquid to replace nitric acid. To this end, it is necessary to analyze the chemical polishing process of aluminum, especially to focus on the role of nitric acid. The main role of nitric acid in aluminum chemical polishing is to inhibit point corrosion and improve the throwing brightness. Combined with the chemical polishing test in pure phosphoric acid, that the special substances added in phosphoric acid should be able to inhibit the point corrosion, slow down the total corrosion, and must have a better leveling and brightening effect

Method 4: Electrochemical surface reinforcement treatment of aluminum and its alloys The process, properties, morphology, composition and structure of ceramic amorphous composite conversion film formed by anodic oxidation deposition of aluminum and its alloy in the process and mechanism of film formation are preliminarily discussed. The process study results show that in the Na _ 2 WO _ 4 neutral mixed system, the controlled membrane formation promoter concentration is 2.5~3.0g/l, The concentration of complexation film agent is 1.5~3.0g/l, Na _ 2 WO _ 4 concentration is 0.5~0.8g/l, the peak current density is 6~12A / dm 2, weak stirring, a complete and uniform series of gray inorganic nonmetallic film layer can be obtained. The thickness of the film layer is 5~10 μ m, and the microhardness is 300 ~ 540 HV, with excellent corrosion resistance. The neutral system has good adaptability to aluminum alloy, anti-rust aluminum, forging aluminum and other series of aluminum alloy can be better film.

Method 5: YL 112 aluminum alloy surface treatment technology YL 112 aluminum alloy is widely used in the structural parts of automobiles and motorcycles. The material needs to be treated before application to improve its corrosion resistance and form a surface layer that is easily combined with an organic coating to facilitate the subsequent surface.