The electrostatic spraying technology of aluminum forgings in construction machinery is a common surface treatment method, which forms a uniform coating on the surface of aluminum forgings by applying the spraying material through electrostatic attraction. The specific steps are as follows:
- Surface pretreatment: First of all, the necessary surface cleaning and treatment of aluminum forgings are carried out to remove impurities such as oil, oxide and dust on the surface to ensure the adhesion of spraying.
- Coating selection: Select electrostatic spraying coatings suitable for construction machinery applications. In general, aluminum-based coatings should have good adhesion, wear resistance, corrosion resistance and weather resistance.
- Electrostatic spraying equipment: Use special electrostatic spraying equipment, including high-pressure spraying gun, spraying room and charge DC power supply. Adjust equipment parameters such as spray distance, voltage and spray speed to ensure uniform spray and improve adhesion.
- Spraying process: After the selected coating is fully stirred, the coating is sprayed on the surface of the aluminum forgings by electrostatic means through the spraying gun. During the spraying process, uniform thickness and coating quality should be ensured to avoid defects such as dripping, foaming or flow marks.
- Curing and baking: After the coating is sprayed, the aluminum forgings need to be sent to the baking chamber or the use of infrared radiation equipment for curing and baking. According to the type of coating and the curing process parameters suggested by the manufacturer, the curing temperature and time are controlled to achieve the ideal hardness and adhesion of the coating.
Adhesion evaluation is a method used to judge the adhesion properties of electrostatic spraying coatings. Common assessment methods include:
- Grid test: Use grid to divide the curing coating, observe whether there is coating peeling phenomenon, and evaluate the grade of coating adhesion.
- Pressure adhesion test: By applying a certain pressure, the relative displacement between the coating and the substrate is measured to evaluate the adhesion performance of the coating.
- Tensile shear test: By applying tensile or shear force, measuring the fracture strength between the coating and the substrate, evaluating the adhesion of the coating.
- Hardness test: Indirectly evaluate the adhesion between the coating and the substrate by measuring the hardness of the coating.
The above is only the general steps and methods of electrostatic spraying technology and adhesion evaluation, and the appropriate process parameters and evaluation methods should be selected according to the actual situation. At the same time, in order to ensure the effect and adhesion of electrostatic spraying, it is recommended to test in practice, and can refer to the industry standards and the recommendations of coating suppliers.
