Selection of the hottest graphite materials

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Selection of graphite materials

Toyo carbon is an electrode material that can meet the needs of different types of molds. Materials can be selected and used according to actual needs. There are many bases for the selection of graphite electrode materials, but there are four main standards:

1 The average particle diameter of the material

the average particle diameter of the material directly affects the discharge condition of the material. The smaller the average particle of the material, the more uniform the discharge of the material, the more stable the discharge condition, and the better the surface quality

for forging and die-casting dies with low surface and precision requirements, it is generally recommended to use materials with coarse particles, such as isem-3; For the electronic universal testing machine with good surface and precision, it is recommended to use an average particle size of 4 μ M or less to ensure the accuracy and surface finish of the processed mold. The smaller the average particle of the material, the smaller the loss of the material and the greater the force between the ion groups. For example, isem-7 is generally recommended to meet the requirements in terms of precision die-casting molds and forging molds; However, when customers have particularly high requirements for accuracy, ttk-50 or iso-63 materials are recommended to ensure less material loss, so as to ensure the accuracy and surface roughness of the mold

at the same time, the larger the particle, the faster the discharge speed and the smaller the loss of rough machining. The main reason is that the current intensity in the discharge process is different, resulting in different discharge energy. However, the surface finish after discharge also changes with the change of particles

2. The flexural strength of materials

the flexural strength of materials is a direct reflection of the strength of materials, showing the tightness of the internal structure of materials. Materials with high strength have relatively good discharge loss resistance. For electrodes with high accuracy requirements, try to choose materials with good strength. For example, ttk-4 can meet the requirements of general electronic connector molds, but for some electronic connector molds with special accuracy requirements, ttk-5 materials with the same particle size but slightly higher strength can be selected

3. Shore hardness of materials

in the subconscious recognition of graphite, graphite is generally considered to be a relatively soft material after a lot of industry research and study of foreign standards. However, the actual test data and application show that the hardness of graphite is higher than that of metal materials. In the special graphite industry, the general hardness test standard is shore hardness measurement, and its test principle is different from that of metal. Due to the layered structure of graphite, it has a very average cost savings of 20% - 40% for customers in the cutting process. It has excellent cutting performance, and the cutting force is only about 1/3 of that of copper material. The machined surface is easy to treat

but it also proposed the development of China's waste foam granulator. Due to its high hardness, the loss of cutting tools during cutting will be slightly greater than that of metal cutting tools. At the same time, materials with high hardness have excellent control of discharge loss. In our EDM material system, there are two kinds of materials with the same particle size that are widely used, one with slightly higher hardness and the other with slightly lower hardness, to meet the needs of customers with different requirements. For example, the average particle size is 5 μ M materials, including iso-63 and ttk-50; The average particle size is 4 μ M, including ttk-4 and ttk-5; The average particle size is 2 μ M, including ttk-8 and ttk-9. It mainly takes into account the biased direction of various types of customers for discharge and machining

4. Inherent resistivity of materials

according to our statistics on the characteristics of materials, if the average particles of materials are the same, the discharge speed of high resistivity will be slower than that of low resistivity. For materials with the same average particle size, the strength and hardness of materials with low resistivity will be slightly lower than those with high resistivity. That is, the discharge speed and loss will be different. Therefore, it is very important to select materials according to the needs of practical applications

due to the particularity of powder metallurgy, each parameter of each batch of material has its representative value with a certain fluctuation range. However, the discharge effect of graphite materials of the same grade is very similar, and the difference of application effect caused by various parameters is very small

the selection of electrode materials is directly related to the effect of discharge. To a large extent, whether the selection of materials is appropriate determines the final situation of discharge speed, machining accuracy and surface roughness

these four data represent the main discharge performance of materials and directly determine the service performance of materials. (end)

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