Powder characterization

Powders are an abundant and diverse class of products that underpin the health and comfort of day-to-day life. From the fluid catalytic cracking catalysts used for oil refining, and metal powders that make up aerospace components, to pharmaceutical formulations, cosmetics and milk powder.

Developing powders fit for every purpose relies on engineering materials from the particle scale through to bulk powder performance. Micromeritics supports such work with a uniquely complete and powerful portfolio of analytical solutions. These characterize:

Particle structure via measurements of:

  • Surface area
  • Porosity and
  • Density

Particle morphology, via measurements of:

  • Particle size distributions, for pure or blended materials
  • Particle shape parameters that define form, regularity, opacity and
  • Surface topography

Bulk powder behavior, via measurements of:

  • Dynamic flow properties
  • Shear parameters such as unconfined yield strength
  • Bulk powder properties including bulk density, compressibility and permeability

Powders are usefully thought of as bulk assemblies consisting of particles, (most usually) air and low levels of moisture. Particle properties often define critical aspects of product performance: the dissolution rate of a drug; catalytic activity; or the surface finish delivered by an abrasive.

However, particle properties also impact bulk powder behavior including flowability, compressibility, permeability and ease of fluidization. These properties, in turn, correlate directly with product and process performance: the fluidization performance of a catalyst; tablet hardness; and the feasibility of recycling an additive manufacturing metal powder.

The knowledgeable manipulation of the form and functionality of particles and powders is essential for commercial success and relies on a sound understanding of all relevant properties. Powder behaviour cannot currently be securely predicted from particle properties. This is why the development of cost-efficient processes and products with competitive performance demands a powder characterization toolkit that extends from particle structure through to bulk powder properties.

Micromeritics have recently published a white paper about powder characterization. The paper is available for download on Micromeritics’ website.