ASTM C1351M-96(2012)

Standard Test Method for Measurement of Viscosity of Glass Between 10⁴ Pa·s and 10⁸ Pa·s by Viscous Compression of a Solid Right Cylinder [Metric]

SIGNIFICANCE AND USE
This test method is well suited for measuring the viscosity of glasses between the range within which rotational viscometry (see Practice C965) is useful and the range within which beam bending viscometry is useful (see Test Method C1350M). It can be used to determine the viscosity/temperature curve in the region near the softening point (see Test Method C338). This test method is useful for providing information related to the behavior of glass as it is formed into an object of commerce, and in research and development.
SCOPE
1.1 This test method covers the determination of the viscosity of glass from 104 Pa·s to 108 Pa·s by measuring the rate of viscous compression of a small, solid cylinder.  
1.2 The values stated in SI units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 29-Feb-2012
• ICS: 81.040.01 - Glass in general
• Technical Committee: C14 - Glass and Glass Products
• Drafting Committee: C14.04 - Physical and Mechanical Properties

Relations

• Replaces: ASTM C1351M-96(2007) - Standard Test Method for Measurement of Viscosity of Glass Between 10⁴ Pa·s and 10⁸ Pa·s by Viscous Compression of a Solid Right Cylinder [Metric]
• Effective Date: 01-Mar-2012
• Referred By: ASTM C1350M-96(2019) - Standard Test Method for Measurement of Viscosity of Glass Between Softening Point and Annealing Range (Approximately 10⁸ Pa·s to Approximately 10¹³ Pa·s) by Beam Bending (Metric)
• Effective Date: 01-Mar-2012

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C1351M − 96 (Reapproved 2012)
Standard Test Method for
Measurement of Viscosity of Glass Between 10 Pa·s and
10 Pa·s by Viscous Compression of a Solid Right Cylinder
[Metric]
This standard is issued under the fixed designation C1351M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Mgh
η 5 2π (1)
30V dh/dt 2πh 1V 11αT
~ !~ !~ !
1.1 Thistestmethodcoversthedeterminationoftheviscos-
4 8
ity of glass from 10 Pa·s to 10 Pa·s by measuring the rate of
where:
viscous compression of a small, solid cylinder.
η = viscosity, Pa·s,
M = applied load, g,
1.2 The values stated in SI units are to be regarded as the
g = acceleration due to gravity, 980 cm/s ,
standard.
t = time, s,
1.3 This standard does not purport to address all of the 3
V = specimen volume, cm ,
safety concerns, if any, associated with its use. It is the
h = specimen thickness at time t, cm,
responsibility of the user of this standard to establish appro-
dh/dt = compression rate, cm/s, and
priate safety and health practices and determine the applica-
α = glassmeancoefficientofthermalexpansion,25°Cto
bility of regulatory limitations prior to use.
the measurement temperature, T, m/m/°C. See Note
1.
2. Referenced Documents
NOTE 1—The term (1+αT) corrects for the specimen dimensional
2.1 ASTM Standards: changes due to thermal expansion. For low thermal expansion glasses, it
−6
can be ignored. However, for a glass with an α of 20×10 /°C at a
C338Test Method for Softening Point of Glass
measurement temperature of 1000°C, this term produces a correction of
C965Practice for Measuring Viscosity of Glass Above the
2%. Only an estimate of α is necessary since the correction is small. Use
Softening Point
twice the room temperature coefficient if data are unavailable.
C1350MTest Method for Measurement of Viscosity of
4. Significance and Use
Glass Between Softening Point and Annealing Range
8 13
(Approximately 10 Pa·s to Approximately 10 Pa·s) by
4.1 This test method is well suited for measuring the
Beam Bending (Metric)
viscosity of glasses between the range within which rotational
viscometry (see Practice C965) is useful and the range within
3. Terminology
which beam bending viscometry is useful (see Test Method
3.1 parallel plate viscometer—a device used to determine
C1350M). It can be used to determine the viscosity/
4 8
the viscosity of glass from approximately 10 Pa·s to 10 Pa·s
temperature curve in the region near the softening point (see
by measuring the rate of change in thickness of a cylindrical
Test Method C338). This test method is useful for providing
specimenbetweenparallelplatesmovingperpendiculartotheir
information related to the behavior of glass as it is formed into
commoncentralaxis.Theequationforcalculatingviscosityby
an object of commerce, and in research and development.
the parallel plate method is:
5. Apparatus
This test method is under the jurisdiction of ASTM Committee C14 on Glass 5.1 The apparatus shall consist of a furnace, a means of
and Glass Products and is the direct responsibility of Subcommittee C14.04 on
controlling and measuring its temperature and heating rate,
Physical and Mechanical Properties.
specimen holders and loading rod, and a means of measuring
Current edition approved March 1, 2012. Published March 2012. Originally
the rate of viscous compression of the glass specimen.
approved in 1996. Last previous edition approved in 2007 as C1351M-96(2007).
DOI: 10.1520/C1351M-96R12.
5.2 Furnace:
Fontana, E. H., “A Versatile Parallel-Plate Viscometer For Glass Viscosity
5.2.1 The furnace shall be electrically heated by resistance
Measurements to 1000°C,” Bulletin of the American Ceramic Society, Vol 49, No.
6, 1970, pp. 594–597.
elements. The dimensions and details of the furnace construc-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
tion are not critical; its cross-section can be circular of 75 mm
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
(≈3 in.) diameter or square of sides of 75 mm. The furnace
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. should have a constant temperature zone that covers the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1351M − 96 (2012)
specimen geometry, including the compression range. Differ-
ences in temperature greater than 2°C within the constant
temperature zone are unacceptable.
5.3 Temperature Measuring and Indicating Instruments:
5.3.1 For the measurement of temperature, there shall be
provided a calibrated Type K, R, or S thermocouple. The
thermocouple shall be housed in a double-bore alumina tube
with its junction placed within 5 mm of the specimen near the
axis of the furnace. The thermocouple shall be referenced to
0°C by means of an ice bath, and its emf measured with a
calibrated potentiometer that can be read with a sensitivity
equivalent to 60.1°C and an accuracy of 60.5°C. Precautions
shall be taken to ensure that the ice bath is maintained at 0°C
throughoutthetest.Alternately,theoutputofthethermocouple
can be measured on a calibrated, direct reading meter (elec-
tronic thermometer) that can be read with a sensitivity of
60.1°C and an accuracy of 60.5°C. See Note 3 for tempera-
ture lag-lead corrections.
5.4 Furnace Control:
5.4.1 Suitable means shall be provided for maintaining the
furnace at a fixed control point and for controlling the heating
and cooling rates. Commercially available programming
equipment provides excellent control. A variable transformer
withmanualcontrolisaninexpensive,butlessadequatemeans
of accomplishing the required control.
5.5 Specimen Holder and Loading Rod:
5.5.1 A typical configuration is presented in Fig. 1. Posi-
tioned horizontally on top of the support stand is a stationary
plate (see Note 2),6mm(; ⁄4 in.) thick by diameter of the
FIG. 1 A Typical Parallel Plate Viscometer
support stand. A movable plate, 6 mm thick by 44 mm
minimum diameter is placed parallel and concentrically above
the fixed plate. (See parallel plates in Fig. 1.) Attached to the
top center of the movable plate in a shrink fit configuration is
5.7.1 Micrometercalipers,whichcanbereadtoanaccuracy
a 9-mm (; ⁄8-in.) diameter centerless-ground alumina rod of
of at least 0.01 mm are required for measuring specimen
lengthsufficienttoreachapproximately150mm(6in.)beyond
dimensions.
the top of the furnace or its supporting structure, or both. This
assembly provides a means for loading the specimen during
6. Preparation of Test Specimen
measurement. Bushings attached to the external frame guide
the shaft with a minimum amount of friction. 6.1 Specimensrequiredforthistestmethodaresmall,right,
circular cylinders. Nominal dimensions are 6 mm (; ⁄4 in.) to
NOTE 2—Alumina and vitreous silica are suitable materials for the
12mm(; ⁄2in.)diameterand3to6mmthick.Specimenscan
assemblycomponents,asarenobleorlowexpansionmetalsusedinpairs.
be either core-drilled from flat stock or sliced from a rod. In
The user must observe temperature limitations for these alternate materi-
both cases, the flat surfaces must be ground and polished to be
als.
plane-parallel to 60.001 mm. Cylinders made by dry pressing
5.6 Extensometer for Measuring Thickness Change:
of frit at high pressure can provide meaningful data.
5.6.1 The means of observing the rate of thickness change
ofthespecimenshouldallowreliablereadingoftotalchangeof
7. Calibration
at least 6 mm. The extensometer shall permit direct reading of
7.1 Direct calibration of the apparatus is accomplished by
0.010 mm and estimates of 0.001 mm. Its accuracy shall be
using standard glasses, such as those supplied and certified by
such that the error of indication will not exceed 62% fo
...