Hexagonal boron nitride (h-BN) powder, as the core material of the evaporation boat, is leading the innovation in the field of vacuum coating. In the vacuum coating process, the evaporation boat needs to withstand high temperature above 1500℃ for a long time, strong corrosive metal melt erosion and high vacuum environment, the traditional graphite evaporation boat is easy to corrode, short service life has been difficult to meet the demand for high-precision coating. BN(CHINA) Technology through the deep plowing material science and process innovation, research and development of high-performance h-BN powder, for the evaporation boat performance jump up to provide the key support.
This h-BN powder has three core advantages: first, its melting point is up to 3000 ℃, the coefficient of thermal expansion is extremely low, can effectively resist the coating process of repeated cold and hot shock, to prevent cracking of the boat body; second, chemical inertia is extremely strong, almost no reaction with aluminum, copper and other active metal melts, to avoid corrosion of the boat body caused by the contamination of the plating layer; lastly, the surface of the internal thermal conductivity of more than 250 W / (m-K), can ensure uniform distribution of heat, significantly support the evaporation boat performance leap. Finally, the in-face thermal conductivity is more than 250 W/(m-K), which ensures even heat distribution and significantly improves the coating efficiency and uniformity of the film layer.
In order to give full play to the potential of the material, BN(CHINA) Technology has systematically optimized the powder. Through continuous calcination process, impurities such as boron oxide and free carbon are effectively removed to ensure stable performance of different batches of powder and reduce the impact of impurities on coating quality. In terms of particle size control, D50 is precisely adjusted within the range of 4-20 μm, with coarse particles building the skeleton support and fine particles filling the voids, so that the evaporation boat has both denseness and bending strength after hot compression molding. In addition, the unique flake morphology design enables the high flake-to-diameter ratio powder to form a horizontally oriented thermal conductivity network in the evaporation boat preparation, further optimizing the thermal conductivity performance.
From material purity to surface engineering, BN(CHINA) Technology transforms every detail of h-BN powders into kinetic energy to improve coating quality. The concept of “powder as solution” not only promotes the development of evaporation boat to precision and high efficiency, but also brings a revolutionary breakthrough of cost reduction and efficiency increase in the vacuum coating industry.
