Certification of Standard Reference Material® 46h: Fineness of cement - Addition of Blaine and Particle Size Distribution

Published: May 03, 2018

Author(s)

Chiara F. Ferraris, Max A. Peltz, Blaza Toman

Abstract

The standard reference materials (SRM) for fineness of cement are SRM 114 and SRM 46h. They are an integral part of the calibration materials routinely used in the cement industry to qualify cements for ASTM C204 (Blaine), C115 (Wagner) and C430 (45 m sieve residue). Being a powder, the important physical properties of cement, prior to hydration, are its surface area and particle size distribution (PSD). Since 1934, NIST has provided SRM 114 for cement fineness and it will continue to do so as long as the industry requires it. Subsequent lots of SRM 114 are designated by a unique letter suffix to the SRM number, e.g., 114a, 114b, …, 114q. A certificate provides reference values obtained using ASTM C204 (Blaine), C115 (Wagner) and C430 (45 m sieve residue) is included with each lot of the material. Since SRM 114p, the certificate also provides the particle size distribution curve by laser diffraction. The current SRM is 114q. In 2007, customers remarked that SRM 114q was too fine to be efficiently used for the C430 calibration. Thus, a new SRM46h was developed by using a coarser cement. This SRM provided values only for C430. In 2016, both SRM 114q and 46h were tested and the expiration date was extended. However, the stocks for 114q are depleting and it is forecast to be sold out in 2 years to 3 years. Thus, it was decided to certify SRM 46h with ASTM C204 (Blaine), C115 (Wagner) and the particle size distribution (PSD) by laser diffraction. Unfortunately, no data were available for the C115 (Wagner). The stock of 46h is available for another 7years to 8 years. Thus, an interlaboratory study was organized by NIST to collected data on Blaine and PSD. The data were analyzed to extract the certified value. This report will provide all the data and analysis used to certify SRM 46h for ASTM C204 (Blaine), and the particle size distribution by laser diffraction (AASHTO T253).
Citation: Special Publication (NIST SP) - 260-190
Report Number:
260-190
Pub Type: NIST Pubs

Keywords

particle size distribution, fineness, cement
Created May 03, 2018, Updated May 03, 2018