ASTM B947-14(2020)e1

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.
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Designation: B947 − 14 (Reapproved 2020)
Standard Practice for
Hot Rolling Mill Solution Heat Treatment for Aluminum Alloy
Plate
This standard is issued under the fixed designation B947; 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.
ε NOTE—Warning moved from previous Note 2 to 5.3 editorially in September 2020.
1. Scope 2. Referenced Documents
2.1 The following documents of the issue in effect on the
1.1 This practice establishes the controls required for hot
date of material purchase form a part of this specification to the
rolling mill solution heat treatment of the 6xxx series alumi-
extent referenced herein:
num alloy plate in Table 1 whenASTM material specifications
allow use of this process instead of furnace solution heat
2.2 ASTM Standards:
treatment. For the alloys listed in Table 1, this practice is an
B209 Specification for Aluminum and Aluminum-Alloy
alternate process to solution heat treatment in a furnace, such
Sheet and Plate
as specified in Practice B918/B918M as the preliminary step
B209M Specification for Aluminum and Aluminum-Alloy
for the attainment of T651-type tempers (see ANSI H35.1/
Sheet and Plate (Metric)
H35.1M).
B557 Test Methods for Tension Testing Wrought and Cast
Aluminum- and Magnesium-Alloy Products
1.2 This practice applies only to hot rolling mill solution
B557M Test Methods for Tension Testing Wrought and Cast
heat treatment of plate for the listed aluminum alloys. Precipi-
Aluminum- and Magnesium-Alloy Products (Metric)
tationhardening(aging),processing,andequipmentcalibration
B881 Terminology Relating toAluminum- and Magnesium-
for aging shall meet the practice and requirements of Practice
Alloy Products
B918/B918M.
B918/B918M Practice for Heat Treatment of Wrought Alu-
1.3 The values stated in either SI units or inch-pound units
minum Alloys
are to be regarded separately as standard. The values stated in
E2281 Practice for Process Capability and Performance
each system are not necessarily exact equivalents; therefore, to
Measurement
ensure conformance with the standard, each system shall be 2
2.3 ASTM Manual:
used independently of the other, and values from the two
ASTM MNL7 Manual on Presentation of Data and Control
systems shall not be combined.
Chart Analysis
1.4 This standard does not purport to address all of the
2.4 ANSI Standard:
safety concerns, if any, associated with its use. It is the
H35.1/H35.1M Alloy and Temper Designation Systems for
responsibility of the user of this standard to establish appro-
Aluminum
priate safety, health, and environmental practices and deter-
2.5 European Standard:
mine the applicability of regulatory limitations prior to use.
EN 485-2 Aluminium and Aluminium Alloys—Sheet, Strip
1.5 This international standard was developed in accor-
And Plate—Part 2: Mechanical Properties
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
3. Terminology
Development of International Standards, Guides and Recom-
3.1 Definitions:
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
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
This practice is under the jurisdiction of ASTM Committee B07 on Light Standards volume information, refer to the standard’s Document Summary page on
Metals and Alloys and is the direct responsibility of Subcommittee B07.03 on the ASTM website.
Aluminum Alloy Wrought Products. Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
Current edition approved Dec. 1, 2014. Published September 2020. Originally 4th Floor, New York, NY 10036, http://www.ansi.org.
approved in 2006. Last previous edition approved in 2014 as B947 – 14. DOI: Available from European Committee for Standardization (CEN), Avenue
10.1520/B0947-14R20. Marnix 17, B-1000, Brussels, Belgium, http://www.cen.eu.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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B947 − 14 (2020)
A
TABLE 1 Ingot High Limit Temperature TABLE 3 Minimum Temperature Entering Quench and Cooling
A,B
Rate in Quench Zone
Ingot Upper Limit Temperature
Alloy
°F [°C]
Min Temp Entering Quench Min Cooling Rate
Alloy
°F [°C] °F/min [°C/min]
6061 1067 [575]
A 6061 870 [466] 600 [316]
These upper limit temperatures avoid the possibility of eutectic melting due to
A
overheating, and include a safety margin of approximately 13 °F [7 °C].
The cooling rate is defined as the average temperature drop per unit of time
when subjected to a constant cooling system from initial slab temperature, down to
400 °F [205 °C], forced cooling allowed at a reduced rate down to 350 °F [175 °C],
and cooling continuing to ambient.
B
These minimum temperatures and cooling rates may be altered when statistical
analysis of mechanical property test data substantiates that the material will meet
3.1.1 For definitions of terms used in this practice, refer to
the tensile property requirements of 7.1 and other required material characteristics
Terminology B881.
such as corrosion resistance.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 load sensor or load thermocouple, n—sensors that are
attached to the production material or a representation of
5. Equipment Calibration and System Accuracy Tests
production material, that supply temperature data of the pro-
(SAT)
duction material to process or test instrumentation.
5.1 Non-contact Sensor System (Remote Sensing System)
3.2.2 rolling slab, n—semi-finished or intermediate product
Calibration and SAT:
produced by hot rolling which is between ingot and plate form.
5.1.1 Initial Calibration—Non-contact sensors shall be cali-
brated prior to initial use by an ISO 17025 orA2LA(American
4. Equipment
Association for Laboratory Accreditation) certified laboratory.
4.1 Aluminum alloy ingots or rolling slabs are preheated It may also be certified by the manufacturer if their calibration
prior to being hot rolled as prescribed in 6.2. Controls shall be process is traceable to NIST or national equivalent. Initial
adequate to ensure that the equipment is operated in a manner calibration shall be within 66°F[63 °C].
which precludes overheating of the ingot or rolling slab or 5.1.2 SAT—Noncontact sensors must be compared weekly
deleterious contamination by the furnace environment. Metal under operating conditions and temperature to the SAT test
temperature shall be monitored and controlled to not exceed
instrument/sensor (5.3); test sensor must be in contact with the
the maximum temperature shown in Table 1 prior to hot ingot, hot rolled slab, or plate within 3 in. [75 mm] of the focus
rolling.
point of the noncontact sensor (see 5.3).The noncontact sensor
must read within 62°F[61 °C] of the contact pyrometry
NOTE 1—Some aspects of the metallurgical structure of the alloy after
system; if not, the noncontact sensor system must be adjusted
solution heat treatment are influenced by the thermal characteristics of the
toreadwithinthestatedtoleranceoranoffsetinoperationmust
heatingequipmentused,andthestartingmicrostructureoftheingot.Some
heating equipment achieves very rapid temperature rise and may require
be used to account for the variation and may then be used for
the metal to be soaked for a period to ensure that sufficient applicable
production.
alloying elements are taken into solid solution. This soaking stage may be
minimized if the alloying elements are substantially in solid solution prior 5.2 Temperature Measuring System Accuracy Test (SAT) for
to charging the metal to the heating equipment (this being accomplished
Contact Systems:
by sufficient prior homogenization/cooling practices).
5.2.1 SAT—The accuracy of temperature measuring sys-
4.1.1 Automatic or manual control and recording devices
tem(s) shall be tested under operating conditions at least once
used to measure temperature at pertinent points in the heating
during each week that the facility is used. The test should be
equipment shall be calibrated as specified in 5.1 and 5.2. Table
made by placing a calibrated test temperature sensing element
2 shows preheat/homogenizing furnace temperature tolerance.
(5.3) to make contact with the surface (ingot, hot rolled slab, or
plate) being measured within 3 in. [75 mm] of the system’s
4.2 The hot rolling and quench equipment and controls shall
sensing element and reading the test temperature sensing
beadequatetoensurethatingotsarecapableofbeinghotrolled
element with a calibrated test potentiometer (see 5.3). The
in accordance with the process requirements for the products
contact system must read within 62°F[61 °C] of the test
being produced, as prescribed in 6.3 and 6.4.
instrument.Ifnot,thecontactsystemshallbecalibratedtoread
4.3 Equipmentforquenchingthehotrolledslabmayconsist
within the stated tolerance or an offset in operation shall be
of, but is not limited to, water or water/glycol mixture in a
used to account for the variation. Once the adjustment or offset
standingwave,quenchtank,spray,orpressurizedwaterdevice.
is in use, the system may then be used for production. When
Controls shall be adequate to assure that the equipment is
the system is equipped with dual potentiometer measuring
operated in a manner which achieves the required quench
systems which are checked daily against each other and agree
conditions in Table 3.
within 62°F[61 °C], the above checks and corrections shall
be conducted at least once every three months.
5.3 Test Instrument/Sensor for SAT—The contact pyrometer
TABLE 2 Homogenization and Pre-heat Furnace
thermocouple(sensor)andtestinstrumentmustbecalibratedto
Temperature Tolerance
a NIST (or equivalent national standard) traceable source
Pre-heat Oven Temperature Range
Alloy
before first use and calibrated within three months of use and
°F [°C]
recalibrated every three months thereafter when used. Calibra-
6061 ±15 [±8]
tion error of the instrument shall be no more than 61°F
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B947 − 14 (2020)
been demonstrated (and documented) that they are not essential to
[60.6 °C] and the sensor shall be within 62°F[61 °C] or
achieving an appropriate degree of process control.
0.4 % of true temperature (whichever is greater). (Warning—
Advice should be sought from the equipment manufacturer to 6.2 Ingotshallbeheatedtoatemperatureappropriateforthe
determine precautions necessary when inserting sensing ele- alloy and shall not exceed the maximum temperatures listed in
ments to avoid incurring any safety hazards.) Table 1 (see Note 3). Table 2 shows the maximum allowable
preheat/homogenizing furnace temperature tolerance. If a re-
5.4 Preheat/Slab Reheat Furnace Calibration and Tempera-
motetemperaturesensingsystemisusedandhasaknownerror
ture Uniformity Survey—For continuous or batch furnaces, the
which exceeds 62°F[61 °C], then the permitted upper bound
type of survey and procedures for performing the survey shall
shown in Table 1 shall be adjusted by an amoun
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