What are the factors that affect the life of diamond tools?

Jan 29, 2018
Diamond tool life factors, not only the process parameters, more is the diamond particle size, concentration, bond hardness and other factors.

(1) diamond size: common diamond size in the range of 60/80 ~ 30/35. The harder the rock is, the finer grain size should be used. Because under the same pressure conditions, the diamond is more and more sharp, is conducive to cut into the hard rock. Also generally large diameter of the saw blade requirements sawing efficiency is high, should be selected with a coarse granularity, such as 30, 40 / 50; the small diameter of the saw blade sawing efficiency low, requires rock sawing smooth section, are advised to use finer granularity, such as 50 / 60 and 60 / 80.

(2) concentration: the so-called diamond concentration is (that is, per unit area contained within the diamond density of diamond in the matrix on the work layer distribution of weight). "Norms" provisions, per cubic centimeter work matrix containing 4.4 carats of diamond when its concentration was 100%, containing 3.3 carat diamond, the concentration of 75%. The volume concentration indicates the amount of diamond in the agglomeration, and the concentration of 1/4 is 100% when the volume of the diamond is occupied. Increasing the diamond concentration is expected to extend the life of the saw blade, because the average cutting force is reduced by increasing the concentration. But increase the depth of the inevitable increase in blade cost, so there is a concentration of the economy and the concentration with osmium cut rate increases and increase.

(3) the hardness of Bond: in general, the higher the hardness of the bond, the stronger the ability to resist wear. Therefore, when the saw cutting abrasive rock, bond hardness should be high; when cutting material soft rock, bond hardness should be low; when the grinding of large and hard rock, bond hardness should be moderate.

(4) force effect, temperature effect and abrasion and dilapidation: diamond saw blade in the process of cutting stone, by centrifugal force, sawing, sawing the role of thermal cyclic loading. As a result of the force effect and temperature effect caused by diamond saw blade frayed donate loss.

Force effect: in the process of sawing, the saw blade is subjected to axial force and tangential force. Due to the action of the force in the circumferential direction and the radial direction, the saw blade is wave shaped in the axial direction and is in the radial direction. These two kinds of deformation can cause the plane of the rock is not straight, the stone waste is much, the noise is big, the vibration is intensified, the early damage of diamond agglomeration, and the life of the saw blade is reduced.

Temperature effect: according to the traditional theory: the effect of temperature on saw is mainly manifested in two aspects: one is lead to agglomeration in the graphitization of diamond; second is caused by the diamond and matrix thermal Yi force of diamond particles premature loss resulting. The new research shows that the heat generated during the cutting process is mainly incoming. Arc temperature is not high, generally between 40 to 120 degrees C. The grinding point temperature is higher, generally between 250 to 700 degrees celsius. The coolant only reduces the average temperature of the arc region, but has little effect on the grinding grain temperature. Such temperature does not result in carbonization of graphite, but will make the abrasive and the workpiece friction performance changes occur, and between diamond and additive thermal stress, and leads to the fundamental bending failure mechanism of diamond. The research shows that the temperature effect is the biggest influencing factor of the saw blade breakage.

Grinding damage: due to the effect of stress and temperature, the saw blade after a period of use often produce wear and damage. In the form of wear and tear, there are the following: abrasive wear, local crushing, large area of broken, fall off, bond along the cutting speed of the direction of mechanical abrasion. Abrasive wear: diamond particles and the friction, edge passivation into the plane, the loss of cutting performance, increase friction. The surface of diamond particles can be made of graphite thin layer, and the hardness is greatly reduced.