Powder Characterization Analysis

—In a Carney flow test, a known powder mass is placed into a cylinder with a specific diameter and height. The cylinder is raised and tilted, and the powder flows out of the cylinder and into a funnel. The amount of time it takes—In a Hall flow test, a known mass of powder is placed into a funnel with a specific diameter and height, the funnel is raised, and the time it takes is measured.

Flow Tests - Hall flow testing and Carney flow testing measure the flow properties of the powder, which is important for determining how a powder behaves during handling, transportation, and processing. Powder characterization testing can involve various methods, either separately or in combination, including:

Material Verification—ICP and ICP-MS Analysis determine the elemental composition of a sample material using a spectrometer, which analyzes vaporized and ionized particles (ICP) or detects ions based on their mass-to-charge ratio (ICP-MS).

Microtrac Laser Diffraction is a non-destructive test method that analyzes diffracted light passing through a sample. This test provides fast and accurate particle size information with minimal sample preparation required. It is highly accurate and precise, making it a valuable tool for ensuring the consistency of product quality.  

Sieve Analysis  – A non-destructive testing technique that involves the separation of particles of different sizes using a series of sieves with progressively smaller mesh sizes. Once all of the material is passed through the sieves, the amount of material remaining on each sieve is weighed, a calculation of the percentage of material in each size fraction is done, and the data is plotted on a particle size distribution curve, which shows the percentage of particles in each size range.

Flow Tests—Hall flow testing and Carney flow testing measure the powder's flow properties, which are important for determining how a powder behaves during handling, transportation, and processing. 

• Hall Flow Test—In a Hall flow test, a known mass of powder is placed into a funnel with a specific diameter and height, the funnel is raised, and the time it takes for the powder to flow through is measured and used to calculate the Hall flow rate. 
• Carney Flow Test—In a Carney flow test, a known mass of powder is placed into a cylinder with a specific diameter and height. The cylinder is raised and tilted, and the powder flows out of the cylinder and into a funnel. The amount of time it takes for the powder to flow through is measured and used to calculate the Carney flow rate.

Apparent Density – Apparent density is a measure of the density of a powder, including any voids or spaces between the particles. It is typically determined by measuring the mass of a known powder volume. Apparent density is an important parameter in powder handling and processing, as it can affect the flow properties of the powder. Powders with a higher apparent density tend to have a slower Hall flow rate, indicating lower flowability. Apparent density is determined as the mass of the powder per unit of volume (g/cm3). 

Tap Density (Packed Density)—A tap density test measures the density of a powder under controlled conditions of tapping or vibration. It is determined by measuring the mass of a powder sample after it has been subjected to a specific number of taps or vibrations. The powder's tap density is influenced by particle size, shape, surface area, and interparticle forces. Tap density is determined as the powder mass per volume unit (g/cm3).

Helium Pycnometry – Helium pyncometry is a highly accurate and precise test that determines the density of materials by measuring the volume of helium gas displaced by a solid sample, which is measured and calculated using the known volume of helium and the mass of the sample. It is particularly effective for materials with high porosity or surface roughness. This method is commonly used in the field of material sciences to determine the density of solid materials, particularly those with small particle sizes or complex shapes. The information this test generates is important for applications where the density of materials affects their performance, such as in the development of lightweight materials for aerospace or automotive applications.