The special binder for lost foam casting coatings is primarily used to enhance drying strength, adhesion, and high-temperature strength of the coating. It helps reduce coating cracking and moisture absorption, thereby simplifying the in-plant preparation process of self-made coatings, improving casting quality, reducing casting defects, and increasing finished product yield.

Features:

1.Compatibility with Carbon Steel Pouring Conditions

With a refractoriness of 1600–1700 °C, the binder system is well matched to the pouring temperature of carbon steel (1450–1520 °C). Common refractory fillers include quartz powder and bauxite, providing strong resistance to molten steel erosion and effectively preventing sand burn-on.

2.Low Gas Generation to Prevent Porosity

The binder system (e.g., CMC combined with bentonite) exhibits low moisture absorption and minimal gas evolution after drying. With properly controlled permeability, it enables the timely discharge of gases generated during foam pattern vaporization, reducing subsurface porosity and related defects.

3.Strong Adhesion with Easy Cleaning

The binder provides excellent hang-on performance. The coating remains crack-free and firmly bonded after drying, and after pouring it peels off in a shell-like form, leaving a smooth casting surface and ensuring high cleaning efficiency.

4.Flexible Processing with Cost Efficiency

Recommended water-to-powder ratio: 1:0.65–0.7. The coating can be applied by dipping, pouring, or brushing, with a coating thickness of 0.8–1.2 mm. The dry powder offers a long shelf life and can be easily prepared by adding water, making it suitable for mass production of carbon steel castings such as flanges, gears, and structural components.

5.Environmentally Friendly and Safe

The binder contains no VOCs. Optimized formulations help reduce the risk of metal back-spray during pouring, thereby improving operational safety.