ASTM B394-18

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.
Designation:B394 −18
Standard Specification for
Niobium and Niobium Alloy Seamless and Welded Tubes
This standard is issued under the fixed designation B394; 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 E29 Practice for Using Significant Digits in Test Data to
Determine Conformance with Specifications
1.1 This specification covers wrought niobium and niobium
E2626 Guide for Spectrometric Analysis of Reactive and
alloy seamless and welded tubes as follows:
Refractory Metals (Withdrawn 2017)
1.1.1 R04200-Type 1—Reactor grade unalloyed niobium,
1.1.2 R04210-Type 2—Commercial grade unalloyed
3. Terminology
niobium,
1.1.3 R04251-Type 3—Reactorgradeniobiumalloycontain- 3.1 Definitions of Terms Specific to This Standard:
ing 1 % zirconium, and 3.1.1 lot, n—a lot shall consist of all material produced from
1.1.4 R04261-Type 4—Commercial grade niobium alloy the same ingot at one time, with the same cross section,
containing 1 % zirconium. processed with the same nominal metallurgical parameters and
heat treated at the same conditions.
1.2 The values stated in inch-pound units are to be regarded
as standard. The values given in parentheses are mathematical
4. Ordering Information
conversions to SI units that are provided for information only
and are not considered standard. 4.1 Orders for materials under this specification shall in-
clude the following information as applicable:
1.3 The following precautionary caveat pertains only to the
4.1.1 Type and grade (Section 1),
test methods portion of this specification. This standard does
4.1.2 ASTM designation and year of issue,
not purport to address all of the safety concerns, if any,
4.1.3 Welding (Section 5),
associated with its use. It is the responsibility of the user of this
4.1.4 Quantityinweight,numberofpieces,anddimensions,
standard to establish appropriate safety, health, and environ-
4.1.5 Chemistry (6.3),
mental practices and determine the applicability of regulatory
4.1.6 Temper designation (Section 8),
limitations prior to use.
4.1.7 Permissiblevariationsinlengthandquantityorweight
1.4 This international standard was developed in accor-
B
(9.2, 9.4, and Table 1 ),
dance with internationally recognized principles on standard-
4.1.8 Quality and finish (10.4),
ization established in the Decision on Principles for the
4.1.9 Sampling (11.2),
Development of International Standards, Guides and Recom-
4.1.10 Hydrostatic or pneumatic test (14.2),
mendations issued by the World Trade Organization Technical
4.1.11 Inspection (Section 15),
Barriers to Trade (TBT) Committee.
4.1.12 Required reports (Section 17), and
4.1.13 Additions to the specification and supplementary
2. Referenced Documents
requirements, as required.
2.1 ASTM Standards:
B391 Specification for Niobium and Niobium Alloy Ingots
5. Materials and Manufacture
E8/E8M Test Methods for Tension Testing of Metallic Ma-
5.1 Material covered by this specification shall be made
terials
from ingots that conform to Specification B391 and that are
produced by vacuum or plasma arc melting, vacuum electron-
beam melting, or a combination of these three methods.
This specification is under the jurisdiction of ASTM Committee B10 on
Reactive and Refractory Metals and Alloys and is the direct responsibility of
5.2 Seamless tubes may be made by any seamless method
Subcommittee B10.03 on Niobium and Tantalum.
that will yield a product meeting the requirements of this
Current edition approved April 1, 2018. Published May 2018. Originally
ɛ1
specification, such as, but not limited to, extrusion of billets
approvedin1989.Lastpreviouseditionapprovedin2009asB394 –09 whichwas
withdrawn January 2018 and reinstated in April 2018. DOI: 10.1520/B0394-18.
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 last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B394−18
TABLE 1 Permissible Variations in Diameter and Wall Thickness
A
Measured at any Location
Variation in Variation in
Outside Inside Variation in
Nominal Outside Diameter, Diameter, Diameter, Wall Thickness,
B
in. (mm) Over and Over and Over and
C,D
Under, in. Under, in. Under, %
B C
(mm) (mm)
0.187 to 0.625 (4.7 to 15.9), excl 0.004 (0.010) 0.004 (0.010) 10
0.625 to 1.000 (15.9 to 25.4), excl 0.005 (0.13) 0.005 (0.13) 10
1.000 to 2.000 (25.4 to 50.8), excl 0.0075 (0.19) 0.0075 (0.19) 10
2.000 to 3.000 (50.8 to 76.2), excl 0.010 (0.25) 0.010 (0.25) 10
3.000 to 4.000 (76.2 to 101.6), excl 0.0125 (0.32) 0.0125 (0.32) 10
A
These tolerances are applicable to only two dimensions, such as outside
diameter and wall, or inside diameter and wall, or outside diameter and inside
diameter.
B
For applicable tolerances for very small tubes, less than 0.187 in. (4.9 mm) in
outside diameter, or very thin wall tubes, less than 0.010 in. (0.25 mm), the
producer should be consulted.
C
When tubes as ordered require wall thicknesses ⁄4 in. (19.05 mm) or over, or an
inside diameter 60 % or less of the outside diameter, a wider variation in wall
thickness is required. On such sizes, a variation in wall thickness of 12.5 % over
and under will be permitted.
D
Ovality measured at any cross section: For tubes with nominal wall thickness
less than 3 % of the nominal outside diameter, the ovality tolerance is double the
tolerance shown in the second and third columns.
TABLE 2 Chemical Requirements
Type 1 Type 2 Type 3 Type 4
(Reactor (Commercial (Reactor Grade (Commercial
with subsequent cold working by drawing, swaging, or
Grade Grade Niobium—1 % Grade
Element
pilgering, with intermediate anneals, until the final dimensions
Unalloyed Unalloyed Zirconium) Niobium—1 %
Niobium) Niobium) R04251 Zirconium)
are reached.
R04200 R04210 R04261
5.3 Welded tubing shall be made from flat-rolled products
Max Weight % (Except Where Otherwise Specified)
Each ingot:
by an automatic or semiautomatic welding process with no
Carbon 0.01 0.01 0.01 0.01
additionoffillermetalintheweldingoperation.Othermethods
Nitrogen 0.01 0.01 0.01 0.01
ofwelding,suchastheadditionoffillermetalorhandwelding, Oxygen 0.015 0.025 0.015 0.025
Hydrogen 0.0015 0.0015 0.0015 0.0015
may be employed if approved by the purchaser and tested by
Zirconium 0.02 0.02 0.8 to 1.2 0.8to1.2
methods agreed upon between the manufacturer and the
(range) (range)
purchaser. The manufacturer must use proper precautions to
Tantalum 0.1 0.3 0.1 0.5
Iron 0.005 0.01 0.005 0.01
prevent contamination during welding.
Silicon 0.005 0.005 0.005 0.005
Tungsten 0.03 0.05 0.03 0.05
6. Chemical Requirements Nickel 0.005 0.005 0.005 0.005
Molybdenum 0.010 0.020 0.010 0.050
Hafnium 0.02 0.02 0.02 0.02
6.1 The niobium and niobium alloy ingots and billets for
Titanium 0.02 0.03 0.02 0.03
conversion to finished products covered by this specification
When specified:
shall conform to the requirements for chemical composition as
Boron 2 ppm . 2 ppm .
Aluminum 0.002 0.005 0.002 0.005
prescribed in Table 2.
Beryllium 0.005 . 0.005 .
Chromium 0.002 . 0.002 .
6.2 The manufacturer’s ingot analysis shall be considered
Cobalt 0.002 . 0.002 .
the chemical analysis for products supplied under this
specification, except for interstitials as specified in 6.3.
Alternately,ananalysisofarepresentativesampleofinprocess
or final product from the same ingot may be substituted.
7. Mechanical Requirements
6.3 When requested by the purchaser at the time of
7.1 The annealed materials supplied under this specification
purchase, the manufacturer shall furnish a report certifying the
shall conform to the requirements for mechanical properties as
values of the interstitial elements (C, O, N, H) on end product
specified in Table 4.
as prescribed in Table 3 for each lot of material supplied. End
product interstitial samples must be taken after all thermal and
8. Temper Designations
chemical processing.
8.1 Unless otherwise stated, the materials supplied under
6.4 Guide E2626 is recommended as a guide, where appli- these specifications shall be in the fully annealed condition,
cable. that is, at least 90 % recrystallized.
B394−18
TABLE 3 Additional Chemical Requirements for Finished Product
The permissible overshipment shall be negotiated for orders
(When Specified by Purchaser)
larger than this quantity.
Type 1 Type 2 Type 3 Type 4
(Reactor Grade (Commercial (Reactor Grade (Commercial
10. Quality and Finish
Unalloyed Grade Niobium—1 % Grade
Element
Niobium) Unalloyed Zirconium) Niobium—1 %
10.1 Finished niobium and niobium alloy tubes shall be free
R04200 Niobium) R04251 Zirconium)
of injurious internal and external imperfections of a nature that
R04210 R04261
will interfere with the purpose for which it was intended.
Max Weight %
Oxygen 0.0250 0.0400 0.0250 0.0400
10.2 The finished tubes shall be visibly free of oxide,
Carbon 0.0100 0.0150 0.0100 0.0150
Nitrogen 0.0100 0.0100 0.0100 0.0100 grease, oil, residual lubricants, and other extraneous materials.
Hydrogen 0.0015 0.0015 0.0015 0.0015
10.3 The finished tubes shall be free of cracks, seams,
slivers, burrs, blisters, and other injurious imperfections ex-
ceeding 10 % of the nominal wall thickness.
TABLE 4 Mechanical Properties for Material, Annealed Condition
(90% Minimum Recrystallized)
10.4 Methods of testing for these defects and standards of
Ultimate Yield Strength Elongation in
acceptability shall be as agreed upon between the manufacturer
Tensile (0.2 % offset), 1-in. (25-mm)
Grade
and the purchaser.
Strength, min, min, gage length,
psi (MPa) psi (MPa) min, %
Type1– 18 00
...