In order to verify the feasibility of the application of low temperature powder on aluminum wheels, this paper selects low temperature curing plastic powder coating and ordinary powder coating for comparison. Firstly, the mechanism of low temperature curing of low temperature powder is analyzed. Secondly, the drying of two powders is tested. Baking characteristics, the baking curve was drawn; the third pair of sprayed hubs were tested for mechanical properties (yield strength and reliability test) and film test (adhesion, gravel impact, water resistance, salt spray test and balance block bonding test). Finally, the analysis and evaluation of the application of low temperature process in the production of aluminum wheels is made.
Powder coating is a rapidly developing field in the entire coating technology. Because its VOC emissions are almost zero, the current background of environmental green development has driven its rapid development. Powder coatings have already been applied on automotive wheels, and their environmentally friendly construction and excellent coating properties have led to rapid development in the automotive parts industry in recent years.
However, the curing conditions of common powder coatings are mostly around 180 °C, and some even up to 200 °C, and the time is about 25 minutes. There are disadvantages of high baking temperature and long time, resulting in high energy consumption and high curing in practical applications. Temperature can also cause parts to become brittle. The automobile wheel hub is the main load-bearing component of the car. It requires not only sufficient mechanical strength but also sufficient toughness to ensure impact resistance. Reducing the curing temperature of the powder coating can increase the toughness of the hub, reduce the energy consumption of the enterprise, and achieve the goal of energy saving and environmental protection.
At present, energy-saving and environmentally-friendly low-temperature curing powder has been widely used in the field of household appliances, effectively reducing energy consumption, but the traditional low-temperature curing powder is used, the leveling property is not good, and the coating of aluminum wheels is more demanding for leveling and appearance. High, so it can not be sprayed on aluminum wheels, so in the automotive aluminum wheel industry, low-temperature curing powder has not been used in large quantities, so if the aluminum wheel industry can use low-temperature curing powder, there will be much room for improvement in energy saving and environmental protection.
To realize the popularization and application of low-temperature powder coating in automotive wheel hub applications, the premise is that the wheel products produced under the low-temperature powder process meet the current automotive component performance standards. In this paper, the powder manufacturers' performance tests on the low-temperature powders for aluminum wheels (corrosion resistance, DSC) Based on differential calorimetry, powder infrared spectroscopy, film compatibility, particle size experiment, resin content, and gravel impact resistance, the aluminum wheel special low-temperature curing powder developed by Guangzhou Qingtian Powder was passed through the aluminum wheel. A series of standard tests, such as mechanical properties, construction technology of low-temperature powder coatings, coating film properties, and coating balance performance, have made a series of feasibility studies on the application of low-temperature curing powders in the aluminum wheel industry.
