ASTM E391-95

Practice for Presentation of Phase Diagrams (Withdrawn 1999)

SCOPE
1.1 This practice covers the drawing of binary phase diagrams and isotherms through ternary phase diagrams for publication.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1994
• Withdrawal Date: 09-Oct-1999
• ICS: 01.100.01 - Technical drawings in general
• Technical Committee: E04 - Metallography
• Drafting Committee: E04.02 - Terminology

Standards Content (Sample)

Designation: E 391 – 95
Standard Practice for
1, 2
Presentation of Phase Diagrams
This standard is issued under the fixed designation E 391; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 6. Locations of Scales on Binary Diagrams
1.1 This practice covers the drawing of binary phase dia- 6.1 The Celsius temperature scale should appear along the
grams and isotherms through ternary phase diagrams for left-hand side of the diagram and should correspond with the
publication. horizontal lines of the centimetre grid. The use of the Fahren-
heit scale along the right-hand side of the diagram is optional.
2. Referenced Documents
6.2 Scales for both weight percent and atomic percent
2.1 ASTM Standards: should be used. It is preferable to place the weight percent
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E 7 Terminology Relating to Metallography
scale along the bottom, and it should correspond with the
2.2 American National Standard: vertical lines of the grid, because the reading of the interme-
ANSI Y15.1-1959 Illustrations for Publication and Projec- diate values is used with weight percent in preparing alloys and
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tion
in plotting results. The atomic percent scale is placed along the
top of the diagram.
3. Terminology
7. Indicating Atomic Ratios in Binary Diagrams
3.1 Definitions—For definitions of terms used in this stan-
dard, see Terminology E 7. 7.1 Atomic ratios are clearly indicated by the scale of
atomic percentages along the top of the diagram. The use of
4. Significance and Use
arrows for this purpose is unnecessary and may be confusing
4.1 Phase diagrams are graphical representations of the
where there is no phase having the stoichometric ratio indi-
equilibrium composition limits of the phases in an alloy system
cated. Therefore, they are not recommended.
as a function of temperature and pressure. Pressure is generally
8. Ternary Diagrams
assumed to be constant at 1 atmosphere (101.3 kPa) in metal
systems. 8.1 Complete presentation of ternary diagrams requires a
4.2 This practice establishes a procedure for publishing
three-dimensional model (a right prism) the base of which is an
phase diagrams so as to maintain congruency regardless of equilateral triangle. Compositions are plotted on the base, and
publication and alloy source.
temperatures perpendicular to the base. However, a perspective
drawing of such a model cannot be measured accurately, and so
5. Grid and Scale for Binary Diagrams
ternary diagrams are preferably published in the form of
5.1 Binary phase diagrams should be plotted on a rectangu-
isothermal sections, or as the projections of certain surfaces on
lar grid having a spacing of 1 cm in each direction. The scale
the base.
to be used on each axis (temperature and composition) should
8.2 Compositions are plotted on an equilateral triangular
be such that intermediate values can be measured easily with
grid (the Gibbs triangle). This triangular grid should have
the use of a scale graduated in millimetres. For example, on the
spacings of 1 cm in each of the three directions. Compositions
temperature scale (ordinates) 1 cm might equal 10, 50, 100, or
should be plotted in weight percent. The selection of scales is
200°C; and on the composition scale (abscissae) 1 cm might
the same as for binary diagrams.
equal 1, 5, 10, or 20 %. The choice will depend upon whether
9. Quasi-Binary Sections of Ternary Diagrams
the diagram covers the whole system or only a part, as well as
the size of the printed reproduction.
9.1 Certain sections perpendicular to the base of the model
and connecting two single-phase regions look like binary
diagrams. They are called quasi-binary diagrams and are very
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This practice is under the jurisdiction of ASTM Committee E-4 on Metallog-
useful. They should be plotted just as binary diagrams are
raphy and is the direct responsibility of Subcommittee E04.02 on Metallographic
plotted. The use of other vertical sections is not recommended.
Terminology and Nomenclature of Phase Diagrams.
Current edition approved July 15, 1995. Published September 1995. Originally
published as E 391 – 69. Last previous edition E 391 – 90.
10. Labeling Phase Fields
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Phase diagrams are also known as equilibrium or constitutional diagrams.
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10.1 Single-phase fields should always be labeled with the
Annual Book of ASTM Standards, Vol 03.01.
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Available from American National Standards Institute, 11 West 42nd Street, phase designation. Two-phase or three-phase fields may be
13th Floor, York, NY 10036.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
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E 391
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FIG. 1 Typical Binary Phase Diagram
labeled if there is ample room. Wherever there is enough room diagram will be easily legib
...