Influence of binder on grinding wheel performance

Bond refers to the material bonded various bonding bond and abrasives. Bonded abrasives usually use vitrified, resin, metal and other bond. Binders can be divided into inorganic binders and organic binders.

Vitrified bond

The main ingredient of vitrified bond are vitreous material with low melting point, such as borosilicate glass, lead glass, etc.

Vitrified bond is characterized by high chemical stability, almost can work in a variety of cooling media, small elastic deformation, brittle, can be made into a variety of hardness levels of grinding tools to adapt to the processing of various hardness of the workpiece. Vitrified bond has good self-sharpening.

Vitrified bond has the advantages：strong grinding force , low grinding temperature and small wear, good shape retention. Vitrified bond can adapt to the role of various coolant and the precision of the grinding workpiece is high.

There are more pores in the grinding wheel, which is conducive to removal chip , chip pocket and heat dissipation, not easy to block and burn the workpiece. The self-sharpening of the abrasives is better, the dressing interval is long and easy to dressing.

The grinding efficiency of single crystal diamond with vitrified bond grinding wheel is higher than metal bond grinding wheel. The wear ratio is very small and the processing cost is low. Therefore, the grinding efficiency of single crystal diamond with ceramic bond grinding wheel can be greatly improved.

In the aspect of grinding PCD cutting tool, the resin bond is soft and easy to deform during grinding, which can not grind PCD cutter effectively. Metal bond grinding tool has poor self-sharpness and low grinding efficiency, and metal bond grinding wheel will cause serious damage to PCD cutting tool edge. Considering grinding efficiency, durability and machining quality of workpiece surface, vitrified bond diamond grinding wheel is the most suitable choice for grinding PCD cutting tools.

Metal bond grinding tool has poor self-sharpness, low grinding efficiency and metal bond grinding wheel will cause serious damage to the edge of PCD cutting tool. Considering grinding efficiency, durability and machining quality of workpiece surface, vitrified bond diamond grinding wheel is the most suitable choice for grinding PCD cutting tools.

In addition to single crystal diamond/PCD cutting tools, vitrified diamond grinding wheel are also mainly used in PCBN cutting tools, cemented carbide and new engineering ceramic materials of rough grinding, grinding and ultra precision grinding, cermet, cast iron, ceramics, gemstones, ferrite, concrete, refractory materials, fiber reinforced plastic grinding and processing.

MoreSuperHard Products devotes to offer an efficiency and economic solution in PCD and CBN cutting tools grinding. We can supply quality PCD grinding wheel at very long life as well as fast cutting.

Resin bond

The resin bond has high bonding strength, the linear speed of high-speed cutting grinding wheel can reach 80-100m/s, and the grinding load of heavy load grinding wheel increases from about 50kg in the past to more than 1000kg.

It is not easy to burn the workpiece in processing, and the resin is easy to carbonize above 230℃. The high temperature in processing makes the resin local carbonization, which produces self-sharpening, improves the sharpness of grinding and reduces the grinding temperature, so as to avoid burning the workpiece.

Resin grinding has certain elasticity, which is beneficial to improve the finish of the workpiece being processed. The choice of graphite, chromium oxide and other polishing materials as fillers can further reduce the roughness.

Moresuperhard resin diamond grinding wheel can high precision grinding cutting tools including PCD cutting tools, drill, reamer, end mill,etc.

Metal bond

Metal bond has been widely used in grinding because of its high bonding strength, good formability and long service life. According to the different production process is divided into sintering, electroplating and brazing.

Sintering process
Sintered abrasives are mostly made of bronze and other metals as binders by high-temperature sintering method. They are characterized by high bonding strength, good formability, high temperature resistance, good thermal conductivity and wear resistance, long service life and can bear large loads. However, the grinding efficiency is low, and it is easy to jam and burn the workpiece. Moreover, dressing of metal grinding wheel is difficult.

Electroplating process
Electroplating abrasives is a kind of abrasives production process in which ni-Co alloy is deposited on the surface of metal matrix and the abrasives are fixed by electrodeposition. Abrasive is actually just mechanical embedded in the coating of metal, the control force for abrasive is small, in the load of high efficiency grinding easy to fall off (or flake) and lead to overall failure.
Because the production process of electroplating abrasives has only one layer of abrasives and uses higher grade abrasives, the processing efficiency of electroplating abrasives is high and the heat dissipation performance is good. Because there is only one layer of abrasive, so the service life is not as good as other binder abrasives, and in the case of the same abrasive particle size, the surface roughness of the workpiece processed by electroplating is poor.

Soldering process
Some transition elements (such as Ti, Cr, W, etc.) are coated on the surface of diamond by brazing, and carbide is formed on the surface by chemical reaction. Through the action of this layer of carbide, diamond, binder, matrix can achieve a solid chemical metallurgical combination, to achieve the real diamond surface metallization.
Brazing technology can realize chemical metallurgical bonding of abrasive, binder and matrix interface with high bonding strength. Due to the high bonding strength, only a small amount of bonding agent is enough to firmly hold the abrasive, abrasive exposure can reach 70% ~ 80%, increase the chip tolerance space, grinding wheel is not easy to block, the use of abrasive is more fully, greatly improve the tool life and processing efficiency.

—EDITOR： Doris Hu

—POST: Doris Hu