Why Does 1μm Diamond Polishing Powder Cause Scratches?
Jun 26, 2026| The same 1μm nominal diamond polishing powder, why does it happen that some can bring a perfect mirror-like effect to the workpiece, while others cause random deep scratches on the surface, resulting in the failure of the workpiece? The core of this problem does not lie in the "nominal value", but in the authenticity of the particle size distribution. In the fields of precision optics, hard alloys, and semiconductor processing, the 1μm indicated on the label usually only represents the median diameter D50, while the actual control level of D90 and Dmax (maximum particle size) determines the polishing quality. If the sorting process in the production is rough, causing a wide range of particle size distribution, then the so-called 1μm micro powder will be mixed with a large number of particles far exceeding the standard (Oversize Particles). These extremely large particles, under the cutting pressure, have a cutting depth far exceeding the design expectation, directly destroying the originally uniform and fine surface texture, resulting in a significant drop in yield.
The random deep scratches on the polished surface are mostly caused by uncontrolled oversized particles or particle aggregates through direct physical damage. When several micrometers or even tens of micrometers of diamond fragments are mixed into the nominal 1μm powder, they cannot roll or micro-cut between the polishing pad and the workpiece as normal micro powder, but become hard "plows". These large particles, before being crushed or falling off, have already left deep grooves and sub-surface micro-cracks on the workpiece surface that are difficult to repair. A hard alloy cutting tool factory in North America once used cheap 1μm diamond powder with a D90 value as high as 3.8μm, resulting in a yield of less than 65% for the front face of the blade. After replacing it with high-quality micro powder from China Super Tech Co., Ltd., which has undergone multiple centrifugal sedimentation classification and strict removal of oversized particles, the yield quickly rebounded to over 96%, fully demonstrating the importance of removing "rogue particles" in ensuring the Ra value meets the standard.
In addition to particle size distribution, particle shape and chemical purity are also key variables affecting the mirror effect. Irregular sharp corners or elongated fragments are prone to stress concentration when subjected to force, causing scratches on the workpiece surface; while metal impurities or oxide inclusions may form secondary pollution sources in the polishing solution. Therefore, high-quality diamond polishing powder must have an equal volume shape (block-like) appearance and high purity (≥99.9%). When selecting, one should not merely compare prices, but require the supplier to provide a complete laser particle size analysis report (COA) and SEM electron microscope photos to judge the actual quality of the product, rather than relying solely on the numbers on the label.
To address this issue, China Super Tech Co., Ltd., leveraging its deep accumulation in the field of superhard materials, provides customers with high-performance synthetic diamond micro powder and comprehensive precision processing solutions. We not only have a rich product line of special metal materials such as titanium alloys, niobium-tantalum, but also adopt advanced precision classification technology in the production of diamond micro powder, strictly controlling Dmax to ensure a narrow and highly consistent particle size distribution for each batch of products. We understand that a stable supply chain is the lifeline of customer production, therefore, we have established a large inventory of standard products to support global rapid delivery and can provide customized services according to the special process requirements of customers, truly achieving one-stop consumable supply from rough grinding, medium grinding to fine polishing.
Whether it is solving the existing polishing scratch problem or optimizing future production processes, China Super Tech can provide strong technical support. We have sufficient inventory, complete specifications and materials, and are committed to helping customers reduce scrap rates and improve smoothness through high-quality products. If you are looking for a diamond polishing powder that can consistently produce a mirror-like finish with no risk of scratches, please feel free to contact us to obtain samples and technical information. Let the professional data and actual test results speak for themselves.