Graphite mold quality diamond saw blade
Sherry Huang
www.boreway.net
2015-10-10 15:36:55
In the hot pressing process synthetic diamond saw blade, the graphite mold charged with the dual role of the heating element and the mold support, the merits of the quality of the graphite mold, fluctuation of the performance parameters of graphite, have a direct impact synthetic diamond tip dimensional accuracy, external shape, the content of the binder in the tip, hardness, bending strength of the base material, the ability of the diamond package inserts, and the cutting performance and service life of the tip.
1. Effect of graphite bulk density, Shore hardness, flexural and compressive strength
2 and open porosity of the graphite
In order to ensure the tip finish, in addition to the graphite mold surface finish is higher, it also requires the graphite particle structure should be fine, open porosity smaller the better, it should generally be less than 13%.
If the volume of low density graphite mold porosity is too high, the hot pressing process, the graphite will head the more metal-binding agent absorbed into the metal of impregnated graphite, so that the tip of the weight loss rate increases, thus changing the head of the metal bond diamond ratio, reduce the adhesive ability of the diamond grip. And even adhesions between the tip surface and the graphite mold, reducing surface finish of the tip.
3, the impact of impurities in graphite
As Sintering graphite mold requires its ash content as low as possible, as high degree of graphitization. If the impurity content of the graphite is too high, too much ash in the hot pressing process, the graphite mold in excess impurities and head of the metal binding agent chemical reaction, and adhered to the surface of the diamond tip to produce dark red marks, affecting the appearance of the diamond tip.
4. Effect of Graphite resistivity
When the graphite mold as synthetic diamond blade in hot heating element in the sintering process is required between the graphite block and the block, resistance between each indenter rate to be consistent, highly uniform. If the resistance between the graphite blocks uneven rate, according to Joule Lenz's law, it will lead to heat between the blocks, between the groups is not the same, the difference between high and low temperature increases. In the hot pressing process the diamond tip, the temperature difference between high and low can cause hardness and bending strength of the base material, but also lead to the base of the diamond package inserts of varying strength capacity, thereby affecting the head wear ratio and cutting ability.
1. Effect of graphite bulk density, Shore hardness, flexural and compressive strength
When the graphite mold plays a supportive role in hot pressing process, it requires the graphite bulk density, Shore hardness, flexural and compressive strength, the higher the better, the bulk density of greater than 1.75g / cm3. As the die head, the bending strength level is more important. If the volume of low density graphite, its hardness, flexural and compressive strength will be lower accordingly, using easily fractured or broken.
2 and open porosity of the graphite
In order to ensure the tip finish, in addition to the graphite mold surface finish is higher, it also requires the graphite particle structure should be fine, open porosity smaller the better, it should generally be less than 13%.
If the volume of low density graphite mold porosity is too high, the hot pressing process, the graphite will head the more metal-binding agent absorbed into the metal of impregnated graphite, so that the tip of the weight loss rate increases, thus changing the head of the metal bond diamond ratio, reduce the adhesive ability of the diamond grip. And even adhesions between the tip surface and the graphite mold, reducing surface finish of the tip.
3, the impact of impurities in graphite
As Sintering graphite mold requires its ash content as low as possible, as high degree of graphitization. If the impurity content of the graphite is too high, too much ash in the hot pressing process, the graphite mold in excess impurities and head of the metal binding agent chemical reaction, and adhered to the surface of the diamond tip to produce dark red marks, affecting the appearance of the diamond tip.
4. Effect of Graphite resistivity
When the graphite mold as synthetic diamond blade in hot heating element in the sintering process is required between the graphite block and the block, resistance between each indenter rate to be consistent, highly uniform. If the resistance between the graphite blocks uneven rate, according to Joule Lenz's law, it will lead to heat between the blocks, between the groups is not the same, the difference between high and low temperature increases. In the hot pressing process the diamond tip, the temperature difference between high and low can cause hardness and bending strength of the base material, but also lead to the base of the diamond package inserts of varying strength capacity, thereby affecting the head wear ratio and cutting ability.
