W. CONSHOHOCKEN, PA - ASTM International has announced two new proposed standards, a standard that addresses test panel preparation and rating specifically for corrosion testing of building projects, and a standard that will provide insight into the relationship between temperature and viscosity.
ASTM WK 30920, Guide for Corrosion Test Panel Preparation and Rating of Coil-Coated Building Products, is being developed by Subcommittee D01.53 on Coil Coated Metal, part of ASTM International Committee D01 on Paint and Related Coatings, Materials and Applications.
According to Ted Best, Scientist, Valspar Corp., and D01.53 member, the standardization of test panel configurations and ratings would allow benchmark comparisons across a broad range of products that includes substrates, pretreatments and coatings. Producers will be able to use the proposed standard, once it has been approved, to develop new products, while users will employ it to verify and compare product performance.
“These comparisons lead to better understanding of product performance as a function of environment, better service life predictions and shorter product development cycles,” said Best.
All interested parties are welcome to join in the development of ASTM WK 30920. “Coil coaters and metal building manufacturers are especially welcome for the valuable input they can provide based on their experience and understanding of market requirements,” said Best.
The viscosity of paints, inks and many related liquid materials varies considerably with temperature. In some cases viscosity can decrease by 10 percent with every 1 °C increase in temperature. A proposed new ASTM standard will provide insight into the relationship between temperature and viscosity.
ASTM WK 33642, Test Method for Measurement of Viscosity of Paints, Inks or Related Liquid Materials as a Function of Temperature, is being developed by Subcommittee D01.24 on Physical Properties of Liquid Paints and Paint Materials, part of ASTM International Committee D01 on Paint and Related Coatings, Materials and Applications.
“It is useful to know the extent of variation, but we do not know of any ASTM standard that establishes the viscosity-temperature variation for these materials,” said Clifford Schoff, Ph.D., Schoff Associates, and Chairman of D01.24. “The relationship has important implications for viscosity measurement in general and specifically for processes such as hot spray and for sagging and leveling on baking.”
The proposed standard will give instruction on how to prepare a viscosity-temperature table or curve. This will be useful when ambient conditions do not allow the measurement at the exact temperature stated in a specification or regulation.
“In addition, knowledge of the viscosity dependence on temperature for a given material will indicate the degree of temperature control required in order to do accurate and precise viscosity measurements,” said Schoff. “Another practical application would be to compare viscosity-temperature behavior of different formulations to better understand the effect of additives or components.”
Schoff says D01.24 welcomes interested parties to join in the ongoing revision of the ASTM WK 33642 draft and also to participate in interlaboratory testing to establish the precision of the proposed standard. In addition to ASTM WK 33642, the subcommittee is also beginning work on a standard for measuring the yield stress of paints, ink and related liquids. Participants are sought for this activity as well.
ASTM International welcomes and encourages participation in the development of its standards. For more information on becoming an ASTM member, visit www.astm.org/JOIN.
ASTM Proposes Two New Testing Standards
July 31, 2011