Inspection of diamond micro powder

Generally, the powder material with the particle size of the abrasive below 54 μm is called micron, and the diameter of the micro powder is also called fine powder with a diameter of less than 5 μm. 3.5 μm and coarser is sorted by a sinking method and 3.5 μm and finer micro powder is sorted by a centrifugal mixture.
Diamond micro powder is mainly used for fine grinding, grinding and polishing of non -metallic hard and crisp materials. Generally, 0 ~ 0.5 μm to 6 ~ 12 μm is used for polishing, from 5 ~ 10 μm to 12 ~ 22 μm for grinding, 20 ~ 30 μm is used for fine grinding. Diamond micro powder is mainly used in the following four aspects: (1) directly used to make grinding paste. It is widely used for the polishing of precision parts such as hard alloy, high aluminum ceramics, optical glass, instrument gems, semiconductor and other materials made of precision parts such as the blade, optical instrument, and electronic devices, and its processing roughness can reach the mirror surface. (2) A large number of fine mills, super fine mills, and electroplating products. (3) It is used to make polycrystal diamond sinters, such as geology, petroleum drills, cutting tools, brushed molds, etc. (4) Made in the manufacturing of grinding and polishing fluid.

1 The granularity test of diamond micro powder
1.1 particle size inspection requirements
Diamond micro powder is mainly used for grinding and polishing. The granularity control is particularly important. As long as there are super-size thick particles, the workpiece will be scratched and the previous work is abandoned. Therefore, the quality inspection of micro powder is an important link to ensure the quality of micro -powder products. Only by taking it seriously can we produce high -quality micro -powder to meet the needs of users' use
The quality inspection of diamond micron powder uses national standards JB/T7990-2012 method inspection. The inspection items mainly include size range, particle size distribution, particle shape, impurities, etc. The main particle size of diamond micro power is M 0/0.25, M 0/0.5, M 0/1, M 0.5/1, M 2/4, M 3/6, M 4/8, M 5/M 10, M 6/12, M 8/12, M 8/16, M 10/20, M 15/25, M 20/30, M 25/35, M 30/40, M 35/55, M 40//M 40// 60, M 50/70. The particle size range of the special application is agreed by the supply and demand parties
1.2 particle size inspection method
In production practice, mainly use laser diffraction method to measure diameter. Commonly used instruments include Mastersizer 2000, the S3500 series of laser -size analyzers of the US Microtrac company, and the X100 laser particle size analysis instrument.
The principle of laser granularity analysis instruments is: when the light is illuminated on the particles, scattering and diffraction occur, and the intensity of scattering and diffraction light is related to the size of the particles. Observing its light intensity, you can apply the theory of Fulang and the fee diffraction theory. The diameter distribution of the particle scattering theory and the MIE scattering theory. When measured, pay attention to the dispersion of the powder to avoid the reunion of powder particles.
The advantages of laser granularity analysis instruments are the convenient and fast measurement, high reproducibility, and can well measure the granular distribution curve and concentration of the sample; the more the spherical particles, the more accurate the measurement, the general use in the industry. Its disadvantage is that the irregular shape and long strip particles are not accurate, and the numerical test is low. This may be related to its own measurement principle: when the software is measured and calculated, the irregular shape and long strip particles are converted into a spherical shape, and then the diameter of the sphere is calculated as the particle size, so the measurement data is low. In order to overcome this shortcoming, in the production practice, the image method and biological microscope method are used for inspection. The main checks of large particles and long strips, laser particle size analyzers and microscope tests are mainly checked.