The appearance of graphite mold is generally coated with an anti-oxidation protective coating, so that the protective layer that is resistant to high temperature and oxidation can reduce the data loss of steelmaking by 19 to half, and the life of the data in use will also add 20 to 60 percent, and then reduce the cost of steelmaking, which is a very good mold processing material.
In addition to the reasonable combination of the substrate with high enough strength and toughness, the appearance function of the graphite mold is very important to the working function and service life of the graphite mold. The surface treatment technology of graphite mold is a systematic engineering that changes the shape, chemical composition, arrangement structure and stress condition of the appearance of graphite mold through surface coating, surface modification or composite treatment technology, so as to obtain the required surface function. Now the most commonly used in graphite mold manufacturing are nitriding, carburizing and hardened film accumulation.
Because the nitriding technology can form an excellent functional appearance, and the nitriding process has outstanding coordination with the quenching process of graphite die steel, and the nitriding temperature is low, there is no need for intense cooling after nitriding, and the deformation of the graphite mold is very small, so the appearance strengthening of the graphite mold is the early selection of nitriding technology, and it is also the most widely used.
Graphite mold carburizing is to improve the overall strength and toughness of the graphite mold, that is, the working surface of the graphite mold has high strength and wear resistance. The hardened film accumulation skills are now more experienced in CVD and PVD. Since the 80s of the last century, graphite molds have been coated with hardened film technology. Under the current skill conditions, the cost of hardened film accumulation skills (mainly equipment) is higher, and it is still only used in some fine, long-life graphite molds, if you choose to establish a heat treatment center, the cost of coating hardened film will be greatly reduced, and more graphite molds If you choose this skill, you can improve the level of graphite mold manufacturing in China as a whole.