The strength of the metal bond on the diamond abrasive is a key factor affecting the life of the metal bond diamond cutting disc. Therefore, researchers at home and abroad have focused on the following aspects of the metal bond diamond cutting disc:
The substitution of the Fe group with a Fe group serves as a binder for the cutting disc for stainless steel, which reduces the production cost. For example, Han Juan et al examined the effect of carbon content on the properties of high-iron-based carcass materials. When the carbon content is 1%, the density of the carcass material reaches a minimum of 7.47g/cm3; when the carbon content is 0.4%, the density of the carcass material reaches The maximum value is 7.65 g/cm3. Chen Xia et al. reduced the erosion of the diamond surface by the binder by adding a small amount of Co to the iron-based binder, and the addition of Co added a dense matrix material on the diamond surface, thereby making the carcass material and diamond more integrated. close. Dai Qiulian et al. found that increasing the content of C, Cu and Ni can improve the mechanical properties of iron-based carcass materials. The sintering temperature of the cutting disc has a significant effect on the hardness and bending strength of the iron-based carcass. The appropriate amount of Zn and Sn Conducive to liquid phase sintering;
Process measures are taken to achieve the ability of the metal bond to hold the abrasive. First, by adding active Ti (TiN2), Cr, rare earth elements, etc. to the sintering raw material; second, plating the active metal or alloy plating layer such as Ti, Cr on the surface of the diamond abrasive grain to improve the holding ability of the bonding agent to the abrasive;
Improve the ability of metal bond diamond cutting discs to be trimmed. At present, metal bond diamond cutting discs are divided into three types: electroplated diamond cutting discs, sintered diamond cutting discs, and single-layer brazed diamond cutting discs. Electroplated diamond cutting discs can only be used in applications where the grinding load is small. Sintered diamond cutting discs are commonly used, and single-layer brazed diamond cutting discs are still in the development stage in China.
The electroplated diamond cutting disc is a cutting disc made by an electrochemical method. The 14 inches cutting disc has the advantages of simple electroplating process, low investment, convenient manufacture, no need for dressing, high work efficiency and long service life. At present, electroplated diamond cutting discs have an undisputed dominant position in high precision, high speed and ultra high speed grinding. The defects of the electroplated diamond cutting disc are as follows: the diamond abrasive grains in the electroplated diamond cutting disc and the coated metal and the substrate are only ordinary mechanical embedding inlaid, and the joint surface thereof does not form a strong chemical metallurgical bond, so the holding force is small. The working surface of the cutting disc is prone to blockage, poor heat dissipation, high grinding temperature and easy to burn the surface of the workpiece.
In order to solve the problem that the abrasive grain of the electroplated diamond cutting disc is not enough, the tool is prone to blockage, and so on, in order to fully exert the advantages of superabrasive, the foreign high-temperature brazing process began in the early 1990s, and a single layer of brazing was developed. Welded diamond cutting disc. In particular, some progress has been made in high temperature brazing diamond cutting discs. For single-layer brazed diamond cutting discs, the bonding strength at the interface provided by high-temperature brazing is high; at the same time, because the thickness of the bonding layer is very thin, the chip space between the abrasive grains is greatly expanded, which is not easy to be blocked, and the effective abrasive grains are used. The cutting edge is more and sharper, and the grinding temperature is greatly reduced, which can effectively prevent the grinding of the burn, especially in the efficient grinding, it can show its unparalleled advantages. It has been used in the preparation of tools such as diamond wire saws, single-layer brazed diamond cutting discs and various grinding heads and sand discs. However, at this stage, industrial-scale single-layer brazing super-hard abrasives are still rarely available.
The sintered aluminum abrasive cutting disc is obtained by mixing a super hard abrasive with a binder powder and then sintering by a powder metallurgy method to form a sintered body of a multilayer structure. The sintered diamond cutting disc has the advantages of high bonding strength, good formability, high temperature resistance, good thermal conductivity and wear resistance, long service life and high load. For the sintered diamond cutting disc, in recent years, some scholars have carried out research on the application of special processing methods to trim the sintered diamond cutting disc, mainly including electrolytic dressing method, electric spark trimming method and composite trimming method.