Electroplated diamond grinding wheel manufacturers believe that resin bonded superhard material tools are superhard tools with diamond or CBN as abrasive, resin powder as binder and appropriate filling materials. They are suitable for superhard tools with different grinding requirements through the process of formula design, weighing and mixing, hot pressing, secondary curing and subsequent processing.
Electroplated diamond grinding wheel manufacturers believe that compared with ceramic bonded or metal bonded superhard abrasives, it has the characteristics of simple manufacturing process, easy availability of raw materials and low cost. It can be widely used in low-quality superhard abrasives with a wide range of processing objects, such as all kinds of difficult to process steel, cemented carbide, glass, ceramics, stone, etc. Resin superhard grinding tools have the advantages of good self sharpening, not easy to block, good surface quality and easy dressing of grinding wheels.
Electroplated diamond wheel manufacturers believe that the resin binder used in resin diamond tools is mainly divided into phenolic resin and polyimide resin. The actual working temperature of phenolic resin diamond tool is lower than 120. Polyimide resin has good heat resistance and can be used for a long time under 260. Because polyimide resin is relatively expensive, especially in recent years, scientists have modified phenolic resin to make its actual working temperature reach more than 200.
Electroplated diamond grinding wheel manufacturers believe that the design of resin bonded diamond tools is mainly based on the following five aspects:
(1) The adhesion must be good. The binder can be evenly distributed on the abrasive surface, keep the abrasive particles firmly in the abrasive tool and firmly adhere to the substrate, which can not only prevent the abrasive from falling off prematurely, but also prevent the separation between the binder and the substrate, so as to ensure the production safety.
(2) High grinding efficiency, good wear resistance and good machining finish (or surface roughness). Electroplated diamond grinding wheel manufacturers believe that due to its elasticity and brittleness, the resin binder has good self sharpening and is not easy to plug, but its wear resistance is poor. Therefore, when studying and designing the binder formula, we should not only consider the high grinding efficiency, but also consider the high wear resistance as much as possible on the premise of ensuring the smoothness requirements. The preparation of binder is very important. The selection of the binder with the best ratio should not only meet the high grinding efficiency, but also meet the good wear resistance. Only by taking both into account can the requirements of grinding and the purpose of reducing cost be achieved.
(3) Good heat resistance. Electroplated diamond grinding wheel manufacturers believe that if the heat resistance of the bond is poor, the grinding tool will not be resistant to high temperature and consume quickly in the process of use. Even if the grinding heat is too high, the grinding tool will burn, crack and fracture. Therefore, select the binder with good heat resistance and add appropriate filler to improve its heat resistance; Wet grinding with coolant as much as possible to improve the durability of grinding tools; If dry grinding is adopted, the feed rate should be as small as possible to improve the durability of grinding tools.
(4) The bond strength must be high. Electroplated diamond grinding wheel manufacturers believe that the strength of bond directly affects the grinding efficiency, wear, workpiece quality and safety performance of grinding tools in use. Therefore, it is necessary to understand the factors affecting the strength of bond. The main factors affecting the strength of the binder are: the addition of filler will increase or reduce the strength of the binder. After the addition of most fillers, the mechanical strength can be improved. Within a certain range, it will increase with the increase of the amount of filler, but the wear rate will decrease. Some fillers, such as graphite and solid molybdenum disulfide, have reduced strength after addition. Fillers should be reasonably selected according to requirements. The forming density of abrasive tools (or the porosity of abrasive tools) will affect the bonding strength. The forming density of abrasive tools is low, the porosity is high, and the strength of binder is low. On the contrary, the strength of binder is high. Therefore, it is necessary to reasonably design the porosity parameters of abrasive tools; The hardening temperature, secondary hardening temperature and heating curve of abrasive forming will affect the strength of the binder. The binder must have appropriate hardness and good wear resistance. The strength of the binder must match the wear rate of diamond (or CBN) abrasive particles, and the abrasive particles shall not fall off prematurely due to the rapid wear of the binder. In this case, the abrasive will not be fully utilized, resulting in waste.