GB/T 6524-2003 (English Version) PDF

Standard No.: GB/T 6524-2003
Language: Chinese, Available in English version
Release Date: 2003
Published By: General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
Latest: GB/T 6524-2003
Replace: GB/T 6524-1986

Scope: This standard specifies the method for calculating particle size distribution by measuring the attenuation of light beam passing through the suspension when the metal powder settles in the suspension due to gravity. This method is applicable to the case where the Stokes equation is satisfied, that is, the laminar flow condition with the Reynolds number less than 0.25, and the particle settling velocity is not affected by Brownian motion. This method is suitable for all metal powders with a particle size between 1 μm and 100 μm, including cemented carbide powder. However, this method is not suitable for the following situations: a) metal powder whose particle shape deviates too far from the equiaxed body, such as flake, fiber and other metal powder with complex shape; b) mixed powder; c) containing lubricant or bonding powders of medicaments; d) powders that cannot be dispersed in liquids. There are upper and lower limits for particle size measurement by sedimentation method (see 5.1). If the largest particle in the sample is outside this range, the viscosity of the liquid should be increased to meet the requirements. Usually, Stokes' law is valid when the initial concentration of powder in liquid is less than 0.5% (volume fraction). In some cases, correct results can still be obtained at concentrations greater than 1% (volume fraction), but their effectiveness must be tested for each material.

GB/T 6524-2003 history

2003 GB/T 6524-2003 Metallic powders-Determination of particle size distribution by gravitational sedimentation in a liquid and attenuation measurement
1986 GB/T 6524-1986 Determination of particle size distribution of metallic powders by method of photosedimentation