What is D50?

The D50 of a particle size distribution refers to the particle size corresponding to the cumulative frequency of 50%. The D50 is a typical parameter to evaluate the quality of the powder. For example, if the D50 of a sample is 5μm by volume distribution, it means that the volume of particles less than 5μm accounts for 50% of the total sample volume, and likewise, the volume of particles greater than 5μm is also 50%. The D50 will be recognized in mathematical statistics as what we call the median.

Similarly, the definition of D10 and D90 can also be given, which are important parameters as well. Some manufacturing industries focus on specific typical values, such as D98 and D99, which are commonly used to indicate the coarse end of the sample.

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