21-6-9 is an allow with high manganese and nitrogen strengthening result in a combination of high temperature oxidation resistance, excellent toughness at cryogenic temperatures and above average corrosion properties. Maximum temperature for continuous service is less than 1600 F (871 C). This alloy retains excellent toughness down to -423 F(-230 C).
Applications Aircraft components, steam and autoclave parts, chemical and pollution control equipment.
Machinability: Due to its relatively high work hardening rate, 21-6-9 is more difficult to machine than most of the austenitic/ 300 series stainless grades. It is quite similar to type 316 stainless. Slow speeds, positive feeds and ample cutting fluids are recommended to overcome work hardening.
Forming: The yield strength of this alloy is nearly double that of conventional 304 stainless. This should be taken into consideration when choosing techniques and required forming pressures.
Welding: TIG, MIG and SMAW methods have been successfully employed. To obtain optimum service performance, AWS E/ER219 filler metal is recommended. Post-weld annealing is required to maximize corrosion resistance.
Heat Treatment: Stress relieving should be performed to optimize performance in operating environments below 1300 F (705 C). Care should be taken in choosing the appropriate temperatures for this operation to protect the properties of cold reduced/ hardened parts. Stress relieving at a temperature between 900-1250 F should have little affect on mechanical properties.
Forging: Material can be forged at 1700-1800 F(927-982 C), followed by air or water quenching. {For heavy sections (over 4″), material should be charged at 1600 F(871 C), equalized at 2000 F(1093 C) and soaked at 2200 F(1204 C) for 1 minute for each inch of thickness.}
Hot Working: This alloy can be successfully forged, upset and headed at temperatures of 2100-2200 F (1149-1204 C).A post-work annealing is recommended to retain properties.
Cold Working: Although higher forces will be required when compared with other austenitic stainless steels, this alloy is readily formed employing most of the common methods.
Annealing: 1800-2150 F (982-1177 C), air cool.
Hardening: This alloy does not respond to heat treatment. It can only be hardened through cold reduction.
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Additional information
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| dimension-1 | .1875", 1-1/2”, 1-1/4”, 1-1/8”, 1-11/16, 1-13/16”, 1-15/16”, 1-3/16”, 1-3/4”, 1-3/8”, 1-5/16”, 1-5/32”, 1-5/8”, 1-7/16”, 1-7/8”, 1-9/16”, 1”, 1/2", 1/4", 1/8”, 11/16", 13/16", 15/16”, 2-1/2”, 2-1/4”, 2-1/8”, 2-11/16”, 2-13/16”, 2-15/16”, 2-3/16”, 2-3/4”, 2-3/8”, 2-5/16”, 2-5/8”, 2-7/16”, 2-7/8”, 2-9/16”, 2", 3”, 3/16", 3/4", 3/8", 5/16", 5/8", 7/16", 7/8", 9/16", Other (Please Specify) |
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