ASTM A989/A989M-23

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: A989/A989M − 18 A989/A989M − 23
Standard Specification for
Hot Isostatically-Pressed Alloy Steel Flanges, Fittings,
Valves, and Parts for High Temperature Service
This standard is issued under the fixed designation A989/A989M; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope*
1.1 This specification covers hot isostatically-pressed, powder metallurgy, alloy steel piping components for use in pressure
systems. Included are flanges, fittings, valves, and similar parts made to specified dimensions or to dimensional standards, such
as in ASME Specification B16.5.
1.2 Several grades of alloy steels are included in this specification.
1.3 Supplementary requirements are provided for use when additional testing or inspection is desired. These shall apply only when
specified individually by the purchaser in the order.
1.4 This specification is expressed in both inch-pound units and in SI units. Unless the order specifies the applicable “M”
specification designation (SI units), however, the material shall be furnished to inch-pound units.
1.5 The values stated in either inch-pound units or SI units are to be regarded separately as the standard. Within the text, the SI
units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used
independently of the other. Combining values from the two systems may result in nonconformance with the specification.
1.6 The following safety hazards caveat pertains only to test methods portions, 8.1, 8.2, and 9.5 – 9.7 of this specification: 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, health, and environmental practices and to determine the applicability of
regulatory limitations prior to use.
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A275/A275M Practice for Magnetic Particle Examination of Steel Forgings
A751 Test Methods and Practices for Chemical Analysis of Steel Products
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.22
on Steel Forgings and Wrought Fittings for Piping Applications and Bolting Materials for Piping and Special Purpose Applications.
Current edition approved March 1, 2018May 1, 2023. Published March 2018June 2023. Originally approved in 1998. Last previous edition approved in 20152018 as
A989/A989M – 15.A989/A989M – 18. DOI: 10.1520/A0989_A0989M-18. 10.1520/A0989_A0989M-23.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
A989/A989M − 23
A961/A961M Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping
Applications
B311 Test Method for Density of Powder Metallurgy (PM) Materials Containing Less Than Two Percent Porosity
E165/E165M Practice for Liquid Penetrant Testing for General Industry
E340 Practice for Macroetching Metals and Alloys
E606/E606M Test Method for Strain-Controlled Fatigue Testing
2.2 MSS Standard:
SP 25 Standard Marking System for Valves, Fittings, Flanges, and Unions
2.3 ASME Specifications and Boiler and Pressure Vessel Codes:
B16.5 Dimensional Standards for Steel Pipe Flanges and Flanged Fittings
2.4 ASME Section IX Welding Qualifications:
SFA-5.5 Specification for Low-Alloy Steel Covered Arc-Welding Electrodes
3. Terminology
3.1 Definitions—For definitions of terms used in this standard, refer to Terminology A941.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 can, n—the container used to encapsulate the powder during the pressure consolidation process that is removed partially or
fully from the final part.
3.2.2 compact, n—the consolidated powder from one can that may be used to make one or more parts.
3.2.3 consolidation, n—the bonding of adjacent powder particles in a compact under pressure by heating to a temperature below
the melting point of the powder.
3.2.4 fill stem, n—the part of the compact used to fill the can that is not usually integral to the part produced.
3.2.5 hot isostatic-pressing, n—a process for simultaneously heating and forming a compact in which the powder is contained in
a sealed formable enclosure, usually made from metal, and the so-contained powder is subjected to equal pressure from all
directions at a temperature high enough to permit plastic deformation and consolidation of the powder particles to take place.
3.2.6 lot, n—a number of parts produced from a single powder blend following the same manufacturing conditions.
3.2.7 part, n—a single item coming from a compact, either prior to or after machining.
3.2.8 powder blend, n—a homogeneous mixture of powder from one or more heats of the same grade.
3.2.9 rough part, n—the part prior to final machining.
4. Ordering Information
4.1 It is the responsibility of the purchaser to specify in the purchase order all requirements that are necessary for material ordered
under this specification. Such requirements may include, but are not limited to, the following:
4.1.1 Quantity (weight or number of parts).
4.1.2 Name of material or UNS number.
4.1.3 ASTM designation and year of issue.
Available from Manufacturers Standardization Society of the Valve and Fittings Industry (MSS), 127 Park St., NE, Vienna, VA 22180-4602, http://www.mss-hq.com.
Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://
www.asme.org.
A989/A989M − 23
4.1.4 Dimensions (tolerances and surface finishes).
4.1.5 Microstructure examination, if required (5.1.5).
4.1.6 Inspection (14.1).
4.1.7 Whether rough part or finished machined part (8.2.2).
4.1.8 Supplementary requirements, if any.
4.1.9 Additional requirements (see 7.2.1 and 16.1).
4.1.10 Requirement, if any, that the manufacturer shall submit drawings for approval showing the shape of the rough part before
machining and the exact location of test specimen material (see 9.3.1).
5. Materials and Manufacture
5.1 Manufacturing Practice:
5.1.1 Powder should be protected during storage to prevent the detrimental pick-up of oxygen and other contaminants.
5.1.2 Compacts shall be manufactured by placing a single powder blend into a can, evacuating the can, and sealing it. The can
material shall be selected to ensure that it has no deleterious effect on the final product. The entire assembly shall be heated and
placed under sufficient pressure for a sufficient period of time to ensure that the final consolidated part meets the density
requirements of 8.1.2.1. One or more parts shall be machined from a single compact.
5.1.3 The powder shall be prealloyed and made by a melting method capable of producing the specified chemical composition,
such as but not limited to air or vacuum induction melting, followed by gas atomization.
5.1.4 When powder from more than one heat is used to make a blend, the heats shall be mixed thoroughly to ensure homogeneity.
5.1.5 The compact shall be sectioned and the microstructure examined to check for porosity and other internal imperfections and
shall meet the requirements of 8.1.3. The sample shall be taken from the fill stem or from a location in a part as agreed upon by
the manufacturer and purchaser.
5.1.6 Unless otherwise specified in the purchase order, the manufacturer shall remove the can material from the surfaces of the
consolidated compacts by chemical or mechanical methods, such as by pickling or machining. This removal shall be done before
or after heat treatment at the option of the manufacturer (see Note 1).
NOTE 1—Often, it is advantageous to leave the can material in place until after heat treatment or further thermal processing of the consolidated compact.
6. Chemical Composition
6.1 The steel both as a blend and as a part shall conform to the requirements for chemical composition prescribed in Table 1. Test
Methods, Practices, and Terminology A751 shall apply.
6.1.1 A representative sample of each blend of powder shall be analyzed by the manufacturer to determine the percentage of
elements prescribed in Table 1. The blend shall conform to the chemical composition requirements prescribed in Table 1.
6.1.2 When required by the purchaser, the chemical composition of a sample from one part from each lot of parts shall be
determined by the manufacturer. The composition of the sample shall conform to the chemical composition requirements
prescribed in Table 1.
6.2 Addition of lead, selenium, or other unspecified elements for the purpose of improving the machinability of the compact shall
not be permitted.
A989/A989M − 23
TABLE 1 Chemical Requirements
A
Composition, %
B
UNS
Niobium
Grade Phosphorus, Sulfur, Tantalum,
Designation Carbon Manganese Silicon Nickel Chromium Molybdenum plus Titanium
max max max
Tantalum
Other
B
Carbon Manganese Phosphorus Sulfur Silicon Nickel Chromium Molybdenum Niobium
Elements
Alloy Steels
K90941 9 % chromium 0.15 max 0.30–0.60 0.030 0.030 0.50–1.00 . . . 8.0–10.0 0.90–1.10 . . . . . . . . .
K90941 9 % chromium 0.15 0.30–0.60 0.030 0.030 0.50–1.00 . . . 8.0–10.0 0.90–1.10 . . . . . .
K90901 9 % chromium, 1 % 0.08–0.12 0.30–0.60 0.020 0.010 0.20–0.50 0.40 max 8.0–9.5 0.85–1.05 Other
Elements
K90901 9 % chromium, 1 % 0.08–0.12 0.30–0.60 0.020 0.010 0.20–0.50 0.40 8.0–9.5 0.85–1.05 N 0.03–0.07
Al 0.04
V 0.18–0.25
B
molybdenum, 0.2 % Nb 0.06–0.10
molybdenum, 0.2 % 0.06–0.10
vanadium plus N
0.03–0.07
vanadium plus
B
niobium and Al 0.04
max
B
niobium and
nitrogen V
0.18–0.25
nitrogen
K31545 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 max . . . 2.7–3.3 0.80–1.06 . . . . . . . . .
K31545 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 . . . 2.7–3.3 0.80–1.06 . . . . . .
K21590 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 max . . . 2.00–2.50 0.87–1.13 . . . . . . . . .
K21590 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 . . . 2.00–2.50 0.87–1.13 . . . . . .
Class 1
K21590 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 max . . . 2.00–2.50 0.87–1.13 . . . . . . . . .
K21590 chromium-molybdenum 0.05–0.15 0.30–0.60 0.040 0.040 0.50 . . . 2.00–2.50 0.87–1.13 . . . . . .
Class 3
A
Maximum, unless otherwise specified.
B
Niobium and columbium are interchangeable names for the same element and both names are acceptable for use in A01.22 specifications.
6.3 The steel shall not contain an unspecified element, for the ordered grade, to the extent that the steel conforms to the
requirements of another grade for which that element is a specified element having a required minimum content.
7. Heat Treatment
7.1 After hot isostatic-pressing, the compacts shall be annealed prior to heat treating in accordance with the requirements of Table
2. At the option of the producer, this anneal shall be a separate operation following powder consolidation or shall be a part of the
consolidation process.
7.2 The alloy steels shall be heat treated in accordance with the requirements of 7.1 and Table 2.
TABLE 2 Heat Treating Requirements
Austenitizing/Solutioning Quenching, Cool Tempering Temperature,
UNS No. Heat Treat Type Cooling Media
A
Temperature, °F [°C] to Below °F [°C] min °F [°C]
Alloy Steels
B B
K90941 anneal 1750 [955] furnace cool
B
normalize and temper 1750 [955] air cool 1250 [675]
B
K90901 normalize and temper 1900–2000 [1040–1095] air cool 1350 [730]
B B
K31545 anneal 1750 [955] furnace cool
B B
K21590 Class 1, 3 anneal 1650 [900] furnace cool
B
normalize and temper 1650 [900] air cool 1250 [675]
A
Minimum unless temperature range is listed.
B
Not applicable.
A989/A989M − 23
7.2.1 Liquid Quenching—When agreed to by the purchaser, liquid quenching followed by tempering shall be permitted provided
the temperatures in Table 2 for each grade are utilized.
7.2.1.1 Marking—Parts that are liquid quenched and tempered shall be marked “QT”.
7.3 See Supplementary Requirement S12 if a particular heat treatment method is specified by the purchaser in the purchase order.
7.4 Time of Heat Treatment—Heat treatment of the hot isostatically-pressed parts shall be performed before or after machining at
the option of the manufacturer.
8. Structural Integrity Requirements
8.1 Microporosity:
8.1.1 The parts shall be free of microporosity as demonstrated by measurement of density as provided in 8.1.2 or by
microstructural examination as provided in 8.1.3.
8.1.2 Density Measurement:
8.1.2.1 The density measurement shall be used for acceptance of material but not for rejection of material. The measured density
for each production lot shall exceed 99 % of the density typical of that grade when wrought and in the same heat treated condition
as the sample. A production lot that fails to meet this acceptance criterion is permitted, at the option of the producer, to be tested
for microporosity in accordance with the microstructural examination as provided in 8.1.3.
8.1.2.2 Density shall be determined for one sample from each production lot by measuring the difference in weight of the sample
when weighed in air and when weighed in water and multiplying this difference by the density of water (Archimede’s principle).
3 3
The equipment used shall be capable of determining density within 60.004 lb/in. [0.10 g/cm ]. Alternatively, at the option of the
producer, it is permitted to use Test Method B311 to determine the density.
8.1.2.3 At the option of the producer, the density shall be compared to the room temperature density typical of wrought alloy steels
or to the density of a wrought reference sample of the same grade heat treated in accordance with the requirements of Table 2 (see
3 3
Note 2). The typical density for alloy steel in the annealed condition at room temperature is 0.28 lb/in. [7.8 g/cm ].
NOTE 2—The actual density of alloy steel varies slightly with composition and heat treatment. For this reason, small differences in the measured density
from the typical density for a given grade of steel may be the result of differences in alloy content, heat treatment, or microporosity. When density values
are measured that are less than the density typical of a given grade of steel, it is appropriate to examine the sample for microporosity by the more specific
metallographic examination procedures.
8.1.3 Microstructural Examination:
8.1.3.1 The microstructure shall be examined at 20-50×, 100-200×, and 1000-2000× and shall be reasonably uniform and shall
be free of voids, laps, cracks, and porosity.
8.1.3.2 One sample from each production lot shall be examined. The sample shall be taken from the component, stem, protrusion,
or test part made from a single powder blend consolidated in the same hot isostatic press using the same pressure, temperature,
and time parameters and heat-treated in the same final heat treatment charge, after hot isostatic-pressing or after final heat
treatment. The microstructure shall meet the requirements of 8.1.3.1.
8.1.3.3 If the sample fails to meet the requirements for acceptance, it is permitted to retest each part in the lot. Each part that passes
the requirements of 8.1.3.1 shall be accepted.
8.2 Hydrostatic Tests—After they have been machined, pressure-containing parts shall be tested to the hydrostatic shell test
pressures prescribed in ASME B16.5 for the applicable steel rating for which the part is designed, and shall show no leaks. Parts
ordered under these specifications for working pressures other than those listed in the ASME B16.5 ratings shall be tested to such
pressures as may be agreed upon between the manufacturer and purchaser.
A989/A989M − 23
8.2.1 No hydrostatic test is required for welding neck or other flanges.
8.2.2 The compact manufacturer is not required to perform pressure tests on rough parts that are to be finish machined by others.
The fabricator of the finished part is not required to pressure test parts that are designed to be pressure-containing only after
assembly by welding into a larger structure. The manufacturer of the compacts, however, shall be responsible as required in 15.1
for the satisfactory performance of the parts under the final test required in 8.2.
9. Mechanical Properties
9.1 The material shall conform to the requirements for mechanical properties prescribed in Table 3 at room temperature.
9.2 Mechanical test samples shall be obtained from the component stem, protrusion, or test part made from a single powder blend
consolidated in the same hot-isostatic press using the same pressure, temperature, and time parameter and heat-treated in the same
final heat-treatment charge. If repair welding is required (see Section 15), the test specimens prior to testing shall accompany the
repaired parts if a post weld heat treatment is done.
9.3 For normalized and tempered parts, or quenched and tempered parts, the central axis of the test specimen shall correspond to
the ⁄4 T plane or deeper position where T is the maximum heat treated thickness of the represented part. In addition, for quenched
and tempered parts, the midlength of the test specimen shall be at least T from any second heat treated surface. When the section
thickness does not permit this positioning, the test specimen shall be positioned as near as possible to the prescribed location, as
agreed to by the purchaser and the supplier.
9.3.1 Alternatively, with prior approval of the purchaser, it is permitted to take the test specimen for the steel parts at a depth (t)
corresponding to the distance from the area of significant stress to the nearest heat treated surface and at least twice this distance
(2t) from any second surface. The test depth, however, shall not be nearer to one treated surface than ⁄4 in. [19 mm] and to the
second treated surface than 1 ⁄2 in. [38 mm]. This method of test specimen location would normally apply to complex parts, or parts
with thick cross-sectional areas where ⁄4 T and T testing (see 9.3) is not practical. Sketches showing the exact test locations shall
be approved by the purchaser when this method is used.
9.4 For annealed alloy steels the test specimen may be taken from any convenient location.
9.5 T
...