{"id":3555,"date":"2026-09-16T10:59:55","date_gmt":"2026-09-16T07:59:55","guid":{"rendered":"https:\/\/www.defencemetal.com\/index.php\/en\/aisi-9310\/"},"modified":"2026-09-25T16:31:12","modified_gmt":"2026-09-25T13:31:12","slug":"aisi-9310","status":"publish","type":"page","link":"https:\/\/www.defencemetal.com\/index.php\/en\/aisi-9310\/","title":{"rendered":"AISI 9310"},"content":{"rendered":"

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AISI 9310 \/ UNS G93106 \/ AMS 6260 \/ AMS 6265<\/h1>\n
DEFENCE METAL<\/span><\/p>\n
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AISI 9310<\/div>\n
UNS G93106 (Carpenter; G93100 also circulates) \u00b7 SAE J404 \/ ASTM A29 band: C 0.07-0.13% – Mn 0.40-0.70% – Si 0.15-0.35% – Ni 3.00-3.50% – Cr 1.00-1.40% – Mo 0.08-0.15% – P and S 0.035% max – balance Fe. The nominal form used in the AMS titles is 1.2Cr – 3.25Ni – 0.12Mo (0.07-0.13C). The Steel Dynamics and TimkenSteel bar handbooks print a slightly wider H-grade based band: Ni 2.95-3.55%, Cr 1.00-1.45%. IT IS AN AEROSPACE GEAR STEEL: high nickel, low carbon. IT IS A CARBURIZING (CASE-HARDENING) STEEL: its carbon is 0.07-0.13% and direct quenching gives no useful hardness; carbon is diffused into the surface to give a hard case over a HIGH-STRENGTH, TOUGH core. THE NICKEL DIFFERENCE: 8620 carries 0.40-0.70% nickel, 9310 carries 3.00-3.50%, roughly six times as much; the difference is not in surface hardness but in how deep into the section the core that carries that hardness stays strong. NO W.Nr. EQUIVALENT IS STATED: the widely quoted 1.6657 \/ 14NiCrMo13-4 match does not hold chemically (see the specification note). IT IS NOT STAINLESS. IT DOES NOT PRECIPITATION HARDEN.<\/div>\n
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Not to be confused with<\/div>\n

AISI 8620<\/a><\/div>\n<\/div>\n

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For what<\/div>\n
Bought for aircraft and helicopter power transmission components: engine and transmission gears, pinions, main gearbox gears, heavy-duty shafts, clutch parts, piston pins. NASA Technical Paper 1390 describes this steel as ‘the material used most frequently to manufacture gears for aircraft today’.<\/div>\n<\/div>\n
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Forms<\/div>\n
Round bar \u00b7 flat bar \u00b7 plate \u00b7 sheet \u00b7 tube \u00b7 forgings. All forms are supplied to order.<\/div>\n<\/div>\n
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Standards<\/div>\n
AMS (verified, 1.2Cr – 3.25Ni – 0.12Mo, C 0.07-0.13% chemistry): 6260 (BARS, FORGINGS AND TUBING; air melting accepted) \u00b7 6265 (same product forms; VACUUM CONSUMABLE ELECTRODE REMELTING – VAR REQUIRED; revision G) \u00b7 6267 (same product forms; ELECTROSLAG OR CONSUMABLE ELECTRODE VACUUM REMELTED – ESR or VAR; revision H\/2012). Cleanliness (alternative levels \u2014 only ONE applies to a given order): AMS 2300<\/b> \u00b7 AMS 2301<\/b> \u00b7 AMS 2304<\/b>. Heat treatment procedure: AMS 2759<\/b>\/7 (Carburizing and Heat Treatment of Carburizing Grade Steel Parts). ASTM: A322 (alloy steel bars, standard grades) \u00b7 A534 (carburizing steels for anti-friction bearings). SAE: J404 (chemistry) \u00b7 J1268 (hardenability bands for H grades). Military: MIL-S-7393 Composition 3 \u00b7 MIL-S-83030. OEM acceptance specifications listed by the sources: Boeing BMS 7-249 \u00b7 Bell 299-947-032 and 299-947-302 (BPS 299-947-032AF) \u00b7 Honeywell EMS 56279 and EMS 56280 \u00b7 HMS 6-1263 \u00b7 Sikorsky SS 9705 \u00b7 HT-5042. EN \/ DIN: THERE IS NO VERIFIED EQUIVALENT; see the specification note.
AMS 6260, 6265 AND 6267 ARE NOT INTERCHANGEABLE. All three share one chemistry (1.2Cr – 3.25Ni – 0.12Mo, C 0.07-0.13%) and all three cover the same product forms (bars, forgings, tubing); THE DIFFERENCE IS THE MELTING METHOD.<\/span><\/div>\n<\/div>\n
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Advantage<\/div>\n
That high core strength is obtained, with numbers, in a low-carbon steel. Its carbon is 0.07-0.13%, the lowest of the three grades on this family of cards, and yet the CORE of the carburized part is 331-363 HBW according to Carpenter, 38 HRC in NASA’s carburized spur gear tests and a nominal 40 HRC\u2026<\/div>\n<\/div>\n
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Welding<\/div>\n
IT IS NOT WELDED AS A GEAR COMPONENT. 9310 is used carburized and ground, not welded; welding is not envisaged as a repair method on flight-critical gears and pinions.<\/div>\n<\/div>\n
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Limits<\/div>\n
1) IT IS NOT STAINLESS. Chromium is 1.00-1.40% and no passive layer forms. Without plating, oil or another protective measure it rusts in damp conditions.
\n2) THE TEMPERATURE LIMIT IS LOW AND IT IS THE REAL LIMIT OF THIS STEEL. NASA Technical Paper 1390 states it plainly: 9310 loses much of its hardness above 394 K (250 F, about 121 C).<\/div>\n<\/div>\n
REQUEST A QUOTE<\/a>All alloy steels →<\/a>TECHNICAL DETAILS ↓<\/span><\/div>\n
Compiled from manufacturer data sheets \u00b7 confirm against the current specification before ordering<\/div>\n<\/div>\n<\/div>\n

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