ASTM C1351M-96 (2022) PDF

Full title and description

Standard Test Method for Measurement of Viscosity of Glass Between 10^4 Pa·s and 10^8 Pa·s by Viscous Compression of a Solid Right Cylinder [Metric]. This test method describes a parallel‑plate viscous‑compression procedure in which the rate of change of thickness of a small, solid, right‑cylindrical glass specimen under load and elevated temperature is measured and used to calculate viscosity in the stated range.

Abstract

This standard specifies specimen geometry (small right circular cylinders), apparatus (parallel‑plate viscometer, furnace, displacement transducer such as an LVDT or equivalent, alumina support/rod), test procedure (apply a known compressive load, heat to target temperature, measure the rate of thickness change), and calculation of viscosity for glasses whose viscosities lie between approximately 1×10^4 Pa·s and 1×10^8 Pa·s. Units are SI (metric). The method is intended for use in research, development and quality control of silicate and related glasses.

General information

• Status: Active — designation C1351M − 96 (reapproved 2022).
• Publication date: Reapproval / effective date: 1 February 2022.
• Publisher: ASTM International.
• ICS / categories: Glass and glass products; typically listed under ICS 81.040 (raw materials and glass).
• Edition / version: C1351M − 96 (original 1996 metric designation), reapproved 2022.
• Number of pages: 4 pages (typical published PDF length).

Scope

This test method covers determination of glass viscosity from about 1×10^4 Pa·s up to 1×10^8 Pa·s by measuring the viscous compression (thinning) rate of small, solid, right‑cylindrical specimens placed between parallel plates under a constant compressive stress and elevated temperature. The values stated in SI (metric) units are the standard. The standard notes that users are responsible for observing applicable safety, health and environmental practices.

Key topics and requirements

• Viscosity measurement range: approximately 1×10^4 to 1×10^8 Pa·s.
• Specimen geometry: right circular cylinders (nominal diameters commonly 6–12 mm, thicknesses typically 3–6 mm) with plane‑parallel faces and polished surfaces.
• Apparatus: parallel‑plate viscometer assembly, furnace capable of controlled temperature, displacement measuring device (LVDT, optical or capacitive transducer), alumina or low‑expansion mounting hardware as specified.
• Test procedure: apply known compressive load, heat specimen to test temperature, record thickness versus time, calculate viscosity using the provided parallel‑plate relation and material/geometry corrections.
• Units and reporting: SI (metric) units; report specimen dimensions, load, temperature, measured deformation rate, calculated viscosity and test uncertainties.
• Safety and applicability notes: does not address all safety concerns — users must establish appropriate safety practices for high‑temperature testing.

Typical use and users

Used by glass scientists, research laboratories, production quality control personnel, materials characterization labs, and R&D groups in the glass and ceramics industries to quantify viscosity near the working/softening range for process control, formulation development, and comparison of glass compositions. It is especially useful when beam‑bending or other high‑viscosity methods are not appropriate because the viscosity is below the annealing/softening window covered by other methods.

Related standards

Commonly used alongside or referenced by other ASTM glass standards, for example: ASTM C1350M (beam‑bending method covering higher viscosities), ASTM C338 (softening point procedures) and terminology standards for glass (ASTM C162). The parallel‑plate viscous compression method complements other viscosity and softening‑point test methods to cover a broad viscosity spectrum.

Keywords

glass; viscosity; viscometer; parallel plate; parallel‑plate method; viscous compression; metric; C1351M.

FAQ

Q: What is this standard?

A: ASTM C1351M‑96(2022) is a standardized test method that defines how to measure the viscosity of glass in the range ~10^4 to 10^8 Pa·s using viscous compression of a small solid right cylinder placed between parallel plates under load.

Q: What does it cover?

A: It covers specimen preparation and dimensions, required apparatus (parallel‑plate viscometer, furnace, displacement transducer), the test procedure (apply load, heat, record thickness change vs time) and the calculation and reporting of viscosity in SI units. It does not attempt to address all safety concerns associated with high‑temperature testing.

Q: Who typically uses it?

A: Glass manufacturers, academic and industrial research labs, materials characterization and QC labs, and formulators who need viscosity data in the stated range for processing and product development.

Q: Is it current or superseded?

A: The metric designation C1351M was originally published in 1996 and was reapproved (reconfirmed) in 2022; the reapproved 2022 edition is active. Users should check for any later revisions or linked standards before use.

Q: Is it part of a series?

A: Yes — it is part of ASTM's suite of glass physical‑property methods that together cover viscosity and softening behavior over a wide range (for example, C1350M covers higher viscosities by beam bending). The C13x series and related C14 committee standards provide complementary methods and terminology.

Q: What are the key keywords?

A: glass; viscosity; parallel plate; viscometer; viscous compression; metric; C1351M.