By a diamond or cubic boron nitride (CBN) abrasive grinding wheel produced, because of its excellent grinding performance, it has been widely used in various aspects of grinding. Diamond grinding wheel is grinding carbide, glass, ceramics, gem high hard and brittle materials effects tools. In recent years, with the rapid development of high-speed grinding and ultra-precision grinding technology, the wheel of a higher requirement, ceramic and resin-bonded grinding wheel can not meet the needs of production, metal bonded grinding wheel because of its combination of strength high, forming a good, long life and other notable features has been widely applied in production.
A sintered metal bonded grinding wheel
Mostly bronze and other metals as a binder, with a high temperature sintering method, high bonding strength, formability, high temperature, thermal conductivity and good wear resistance, long life, can withstand a greater load. Because the wheel during the sintering process there is inevitably shrink and deformation, before using the wheel must be shaped, but more difficult dresser. Currently used in the production of roller wheel in shaping not only time-consuming trimming and finishing process of shedding the diamond particles are more dressing wheel itself, and a great, low shaping precision.
In recent years, scholars from various countries have been carrying out a special processing method applied finishing work metal bond diamond wheel, mainly electrolytic dressing method, EDM trimming method and composite repair method. Electrolytic dressing method faster, but shaping accuracy is not high; high precision EDM shaping trimming method, but also can shaping dressing, but the plastic is slower; composite trimming method electrolytic spark composite trim, mechanical Composite trimming method like dressing better, but the system is more complex, so the problem sintered diamond grinding wheel dressing still not been solved. Further, since the grinding wheel determines the manufacturing process is a random surface topography, geometry of various abrasive grains, and the distribution in the height of the cutting edge are inconsistent, so only a small number of high cutting edge to cut the workpiece, the grinding limit further improve the quality of grinding and grinding efficiency.
Second, the plated metal diamond wheel
Electroplated diamond grinding wheel advantages:
① plating process is simple, low investment, easy to manufacture;
② without dressing, easy to use;
③ monolayer structure determines it can reach a very high work rate, currently abroad, has reached 250 ~ 300m / s;
④ Although only a single layer of diamond, but still have enough life;
⑤ For higher precision roller and wheel, it is the only method of producing plating.
It is because of these advantages, plating wheel occupies undisputed dominant position in the high-speed, ultra-high speed grinding. Electroplated diamond grinding wheel defects: in combination with the metal coating and the abrasive surface of the substrate does not exist a strong chemical metallurgical bonding, mechanical abrasive actually just being embedded in the plating metal embedded in, and thus small gripping force, the diamond particles in the load heavier efficient grinding easy to fall off (or plating flaking) and lead to an overall failure; to increase the gripping force is necessary to increase the thickness of the coating, the result is highly abrasive and bare chip space is reduced, prone to clogging wheel, cooling effect is poor, the surface prone to burn. At present, the electroplated grinding wheel manufacturing has not been implemented according to the requirements of process conditions optimized design the best topography wheel, these inherent drawbacks of a single layer of electroplated diamond grinding wheel is bound to greatly limits its application in efficient Grinding.
Third, the single-brazed diamond wheel
In order to give full play to the role of diamonds, to try to increase the bond and diamond holding force, increase the bonding strength of the wheel. High temperature brazing single grinding wheel overcome disadvantages of electroplated grinding wheel, the diamond can be realized, metallurgical chemical bond, among the metal matrix binding, binding with high strength, the thickness of bonding layer will remain only on the grind grain height of 20% to 30% will be able to load large high speed and efficiency in grinding firmly hold on abrasive, abrasive grinding wheel the solder exposed height of up to 70% to 80%, thus increasing the chip space, clogging wheel, the use of abrasive more fully. Under the same processing conditions electroplated grinding wheel, single-temperature brazing superhard abrasive grinding wheel power, power loss, lower grinding temperature, mean higher operating speed can be achieved, which in 300 ~ 500m / s more speed grinding has a special significance.