numbering systems for alloys ref: “engineering materials – properties and selection”, k.g....
TRANSCRIPT
Numbering Systems for Alloys
Ref: “Engineering Materials – Properties and Selection”, K.G. Budinski and M. K. Budinski, 7th ed., Prentice Hall, 2002 (Chap. 8 – 16)
What do these codes mean?
AISI 1020 steel ASTM A 29 grade 1020 steel UNS G10200 SAE 1006
6061-T6 3003-H38
What You Should Include in the Specifications of a Material?
Description: e.g. steel, hot-finished, low-carbon, bar, ASTM A29 grade B
Dimension Chemical composition Mechanical properties Dimension tolerance: LWH, flatness, etc. Finish: hot-rolled, cold rolled, patterned Special requirements: heat treatment,
texture, etc.
Some Specifications applicable to Steel Products and other Metals
Specifications
SAE-AISI Society of Automotive Engineers – American Iron and Steel Institute
ASTM(UNS)
American Society for Testing and Materials (www.astm.org)
ASME American Society of Mechanical Engineers
MIL U.S. Department of Defense
AMS Aerospace Materials Specification
BS British Standards Institution(http://www.bsi-global.com/index.xalter)
EN European Committee for Standardization (http://www.cenorm.be)
Unified Numbering System (UNS) Developed by ASTM and
SAE Not a specification but
only identify an alloy covered by other standards
The 5 digits closely related to the original identification system. E.g. AISI 1020 = G10200
Adopted by the Copper Development Association as official identification system for Cu alloys
Most Frequently Used Carbon and Alloy Steels in the US
SAE 1010: formed sheet-metal parts SAE 1020: general machine applications SAE 1040: flame- or induction-hardened
parts ASTM A36: structural steel SAE 4140: high-strength machine parts SAE 4340: high-strength machine parts SAE 8620: carburized wear parts
Tool Steel Types High alloy content and thus high hardenability Melted by electric furnace for cleanliness and
alloy content control Melted in small heats and subjected to tight
quality control
A Repertoire of Stainless Steels
Type Uses
430S43000
For rust resistance on decorative an nonfunctional parts
416S41600
Hardened to 30 HRC and use for jigs, fixtures and base plates
420S42000
Harden to 50-52 HRC for tools that do not require high wear resistance (e.g. injection-molding cavities, nozzles, holding blocks, etc)
440CS44004
Harden to 58-60 HRC for cutting devices, punches and dies
A Repertoire of Stainless SteelsType Uses
303S30300
For fasteners and shafts where only rust or splash and spill resistance are needed
304/L All types of chemical immersion
316/L All types of chemical immersion where 304 is not adequate
17-4 PHS17400
High stress fasteners, shafting, agitators and machine supports; age hardened
17-7 PHS17700
Harden to condition CH900 for chemical-resistant springs
Wrought Aluminium Alloys – Aluminum Association designation system
Major Alloying Elements Series
Commercially pure aluminium (99% min) 1000
Copper (major alloying element) 2000
Manganese 3000
Silicon 4000
Magnesium 5000
Magnesium and silicon 6000
Zinc 7000
Other elements 8000
Unused series 9000
Second digit designates mill control on specific elements
The last two digits have no significance,
except…
Indicate the Al content above 99%, e.g. 1040
has 99.40% Al
Cast Aluminium Alloy Designations
Major Alloying Elements Series
Aluminium + silicon 1-99 (old system)
99.5 min. aluminium 1xx.x
Copper 2xx.x
Silicon + copper or magnesium 3xx.x
Silicon 4xx.x
Magnesium 5xx.x
Unused series 6xx.x
Zinc 7xx.x
Tin 8xx.x
Other Element 9xx.x
The last digit indicates product
form: 0 for a casting, 1 for ingot form
Additional Designation of the state of the Aluminium Alloy
Al alloys can be precipitation hardened and work-hardened to different extents.
xxxx-F As fabricated, no special control
xxxx-W Solution heat-treated (used only on alloys that naturally age harden)
xxxx-O Annealed (Wrought alloys only)
xxxx-H Strain hardened (cold worked to increase strength), wrought alloys only
xxxx-T Thermally treated to produce effects other than F, O, or H
Types of Strain Hardening and thermal treatment
xxxx-H1 Strain hardened only
xxxx-H2 Strain hardened and partially annealed
xxxx-H2 Strain hardened and stabilized by low-temperature thermal treatment
xxxx-H4 Strain hardened and lacquered or painted
Degree of Strain Hardening
The second digit indicate the degree of strain hardening
1 indicates smallest amount of cold-work and 8 indicates maximum of cold work
xxxx-H_2 Quarter-hard
xxxx-H_4 Half-hard
xxxx-H_6 Three-quarters hard
xxxx-H_8 Full-hard
Temper Designations
xxxx-T1 Cooled from a hot working temperature and naturally aged
xxxx-T2 Cooled from an elevated temperature, cold worked, and naturalled aged (means annealed for cast products)
xxxx-T3 Furnace solution heat treated, quenched and cold worked
xxxx-T4 Furnace solution heat treated, quenched, and naturally aged
xxxx-T5 Quenched from a hot-work temperature and furnace aged
Temper Designations
xxxx-T6 Furnace solution heat treated quenched and furnace aged
xxxx-T7 Furnace solution heat treated and stabilized
xxxx-T8 Furnace solution heat treated, quenched, cold worked, and furnace aged
xxxx-T9 Furnace solution heat treated, quenched, furnace aged and cold-worked
xxxx-T10 Quenched from an elevated temperature shaping process, cold worked, and furnace aged
Other variations can be denoted by adding more digits after these designations
Examples
3003-H38: 3003 alloy cold finished to full hard temper and stress relieved by a low temperature treatment
6061-T6: 6061 alloy, solution heat treated and furnace aged hardened.
Most commonly used Aluminium alloys
Wrought alloys 1100 (pure Al) 2024* 3003 5052 6061* 6063* 7075*
Sand Cast 355.0*
Die Cast 380.0
*: can be age hardened
Blue shaded: mainly for aerospace applications