Scientific Facts about Diamond Micro Powder

Definition of Diamond Micro Powder

In the conventional sense, diamond micro powder refers to powder with a particle size less than 54 microns, processed from diamond as a raw material. In recent years, with the continuous expansion of new application fields, the particle size of many diamond micro powders has far exceeded 54 microns.

Classification of Diamond Micro Powder

There are many types of diamond micro powder. The most common type is produced using low-strength synthetic diamond as the raw material, and through processes such as crushing, purification, and grading.

Sources of Raw Materials

Based on different sources of raw materials, diamond micro powder can be divided into natural diamond micro powder and synthetic diamond micro powder. Low-grade natural diamonds, which cannot be used for jewelry processing, can be broken down by ball milling to produce diamond micro powder for industrial grinding and polishing, such as for the post-processing of gemstones, precision parts, and so on. With the rapid development of industry, the demand for diamond micro powder in the grinding and polishing field has dramatically increased, and the production of natural diamond micro powder is far from meeting the market demand. The advent of synthetic diamonds has resolved this issue, providing ample raw materials for diamond micro powder. Synthetic diamond micro powder is widely used in grinding hard and brittle materials.

Diamond Crystal Structure

Based on different diamond crystal structures, diamond micro powder can be divided into single crystal diamond micro powder and polycrystalline diamond micro powder. Since single crystal diamond micro powder has high production and wide application fields, the industry generally refers to diamond micro powder as single crystal diamond micro powder. Single crystal diamond micro powder is made from synthetic diamond single crystal abrasive grains, which are crushed, shaped, and processed using a special process method for superhard materials. The particles retain the single crystal characteristics of single crystal diamonds. They have cleavage planes and tend to break along these planes under external force, exposing new "cutting edges." Polycrystalline diamond micro powder consists of micron and submicron polycrystalline particles formed by the bonding of diamond grains with diameters of 5~10nm through unsaturated bonds, having high toughness with internal isotropy and no cleavage plane.

Crushing and Shaping of Diamond Micro powder

Crushing and shaping are critical steps in the production of diamond micro powder. Previous production processes mainly used ball milling for crushing, which focused on crushing with moderate low-speed mechanical impact. Nowadays, it has been replaced by jet milling.

Working Principle of Jet Milling

Compressed air is injected into the grinding chamber at high speed through a nozzle. The diamond raw material repeatedly collides, rubs, and shears at the intersection of multiple high-pressure airflows, and is then crushed. Particles are fractured by high-speed collisions, and their surfaces are ground and shaped through friction and shearing.