Faster, automated Fisher number measurement with the Sub-Sieve Autosizer II
Boosting the productivity of particle sizing via the air permeability technique
Norcross, GA, USA – 03 December 2019 Micromeritics Instrument Corp., a global leader in material characterization technology, today launched the new highly automated Sub-Sieve Autosizer II (SAS II), an instrument that boosts the productivity and accuracy of particle sizing via the air permeability technique, a benchmark in many industries. A direct and substantially improved successor to the renowned Fisher Model 95 SubSieve Sizer (FSSS), it generates ‘Fisher numbers’ which are highly consistent to those of its predecessor. With easy-to-use functionality and electronic data recording, the new SAS II is particularly useful for those complying with specific ASTM standards including E2980, E2651, B330-12 and B330-15 for metal powders and C721-15 for alumina and silica powders (ceramics).
The SAS II delivers particle size measurements in the range 0.2 to 75µm, a range that tends to be too fine for economic and/or accurate sizing by sieve analysis. It utilizes the non-destructive air permeability technique which was commercialized many decades ago specifically to meet the requirement to size finer powders. The resulting ‘Fisher numbers’ are a critical part of established or historical specifications for a significant number of products. The technique involves measuring the pressure drop across a packed bed of sample at a defined air flow rate. The correlation between these two parameters is related to the particle size, or more specifically the specific surface area of a sample, via the Carman-Kozeny equation.
Integrated software makes the new SAS II quick and easy to set-up with a real-time data display simplifying method development. Fully automated measurement sequences include computer-controlled sample compaction and pressure stability for high repeatability. Reports are automatically generated and readily customized to company requirements, while security features safeguard measurement methods and configuration parameters from unauthorized change. In combination these features allow users to efficiently and reliably generate and record the ‘Fisher numbers’ required for QC and comparative testing, with minimal manual intervention.