Today there is a rough diamond that complies with regulatory document TU 47-2-73. However, diamond powders that are manufactured in accordance with GOST 9206-80E are used more actively, since they can be obtained from synthetic types of diamonds, and not just from natural ones.
Powder Description
There is another abrasive, that is, not a diamond raw material, which is also used, but it is inferior in such quality as hardness. The requirements for diamond powder are also much higher, especially with regard to grain size and strength.
There is a main parameter, which determines the further scope. This parameter is the brand of diamond and, accordingly, the brand of powder obtained from it. In addition, an important role is played by such an indicator as the granularity of diamond powder and the concentration of this raw material in the cutting layer of the tool. It is worth noting that, in essence, each diamond grain is a working cutting edge of the tool. For this reason, each grain should provide maximum efficiency during operation at any position of the tool.
Powder grades according to GOST
As mentioned earlier, GOST diamond powder 9206-80E is a document that determines the quality indicators of raw materials. In it there is a division of the substance into certain brands.
In this case, we are talking about the classification of powder, which can be obtained only from natural diamond. There are 5 grades in total, and the main difference between them is the content of strong grains with an isometric shape. The powder is labeled as A1, A2, A3, A5 and A8. The number after the letter A indicates the number of isometric grains in diamond powder in tens of percent. In other words, for example, A3 will contain 30% of isometric diamond grains. There is also a category that is emitted as micropowders. They can also be obtained only from diamonds of natural origin, and they are divided into two categories - AM and AN. AM is a group of powders in which the abrasive ability is at a normal level, AN is a substance in which this level is considered elevated.
Synthetic substances
As for synthetic diamonds, the powders obtained from them also have a classification, and they also differ in their operational and physicochemical properties. The same GOST is used for them as for natural ones. According to this regulatory document, synthetic powders are divided into two groups:
- the first group is a powder obtained from single-crystal diamonds and labeled AC2, AC4, AC6, AC15, AC20, AC32, AC50;
- the second group is a powder obtained from polycrystalline diamonds of the brands APBI, ARK4, ARSZ.
It is worth adding here that recently, especially durable synthetic single crystals have been used to manufacture tools used in the industry for mechanical processing. They make powder, which is labeled as AC65, AC80 and AC80T.
Brand Description
Diamond powder, which is labeled as AC2, may also sometimes be called ASO. A feature of raw materials is that grains are mainly represented as aggregates with a developed surface. They exhibit increased fragility, and the main area of their application is organic ligaments in tools used for polishing stones.
The powder of the next brand, that is, AC4 or ACP, consists not only of aggregates, but also of splices, and they are used for tools used for finishing polishing of stone.
Powder AC6 or ACB is already a more durable category, since grains are presented in the form of imperfect crystals, their intergrowths and fragments. Due to their great strength, they are already used on metal bundles of stone processing tools.
AS15 diamond powder or ASK is represented by high-strength grains in the form of whole crystals, their fragments and splices with a grain coefficient of not more than 1.6. As for whole crystals, they have a small flaw, which lies in an imperfect form. This powder is actively used on tools with a metal bond, which are intended for grinding stone with an average strength.
Next is the AC20 brand. The powder in this case consists of the same crystals, debris, and aggregations as AC15, with only one difference - the shape factor of the grains is not more than 1.5. Scope - tools for grinding stone. AC32 is a raw material that is already presented in the form of well-faceted grains of crystals, their fragments. The main difference is the increased strength coefficient, as well as the coefficient of the grain itself, not more than 1.2.
The most valuable brand is AC50. Also, the powder is presented in the form of whole, well-faceted grains of crystals and their fragments, but the shape factor is even higher and is no more than 1.18. It is used for tools designed for milling and edging the most durable stone.
Polycrystal Powder
It is worth noting that the use of polycrystals to obtain a powder is also considered quite promising. Polycrystals themselves are conglomerates of small, intergrown diamonds that are connected by a charge material and are used in their synthesis. Such a binder of the elements may be iron, nickel, chromium and other elements. Three main categories of polycrystalline grades of powders were previously indicated, however, only two of them are used to create tools - these are ARK4 and ARS3.
Diamond drilling
This operation is considered the most effective and fast if it is necessary to obtain an even cylindrical hole in a sufficiently strong material. The main difference between the use of a diamond tool from a jackhammer or a perforator is that the hole is obtained not only perfectly straight, but also without the slightest cracks. In addition, the diamond drilling process is very quiet and virtually effortless. The installation, which is used for this type of work, does not have a percussion mechanism, and the hole is cut through using a nozzle for a cutting tool, which is made of rough diamonds. It is thanks to this that you can get a perfectly even hole in any material, at any angle and almost any depth.