Alloy

3312

AISI/SAE 3312 a 3 ½% Nickel-Chromium Case Hardening Alloy Steel
Typical Analysis
C Mn P S Si Ni Cr
.11 .47 .010 .002 .27 3.33 1.47
Characteristics
  • High alloy carburizing grade for those heavy-duty applications requiring high core strength, toughness and fatigue resistance over and above the widely used AISI 8620. Core strengths in the order of 170,000 psi (1172 N/mm2) are attainable. It is the preferred grade for carburized parts in severe operating conditions with excellent low-temperature properties. 3312 may also be used in the heat treated, non-carburized condition for many applications requiring extra strength and toughness. It is normally supplied in the annealed condition and hardness HB 212 would be typical.
Typical Applications
  • Heavy-duty gears, pinions, spline shafts, piston pins, transmission components, rock drilling bit bodies, plastic molds, etc.
Typical Heat Treatment
  • Forging
    • Commence 1215℃ max.
    • Finish 925℃ Bury in Mica.
  • Annealing
    • 840℃ Furnace cool
  • Normalizing
    • 900℃ Air cool
  • Hardened & Tempered (Uncarburized) - Heat to 815℃/ 840℃ and oil quench or Heat to 840℃/ 870℃ and air quench, then temper at 200℃/ 650℃ according to properties required.
  • Case Hardening - single refining treatment. After carburizing at 900℃/ 925℃, cool to RT. Reheat to 775℃/ 800℃, oil quench and temper at 200℃.
Mechanical Properties
  • Typical as supplied, Annealed.
  • Tensile Strength – 102,000 psi
    • 2Tensile Strength – 704 N/mm
  • Yield Strength - 80,000 psi
    • 2Yield Strength – 552 N/mm
  • Elongation - 24%
  • Reduction of Area - 65%
  • Hardness - HB 212
  • Machinability - 40
AISI/SAE 3312 Mechanical Properties - UNCARBURIZED (Hardened & Tempered)
Size - inches 1" Dia 4" Dia
Tensile Strength, psi 136,000 131,500
Tensile Strength, N/mm² 938 907
Yield Strength, psi 117,500 108,000
Yield Strength, N/mm² 810 745
Elongation (%) 19 17
Reduction of Area (%) 63 57
Izod Ft./Lbs. 83 68
Izod Joules 113 92
HB of Core 293 285
AISI/SAE 3312 Mechanical Properties - CARBURIZED - Single refining (Hardened & Tempered)
Size - inches 1" Dia 4" Dia
Tensile Strength, psi 173,000 152,000
Tensile Strength, N/mm² 1,193 1,048
Yield Strength, psi 132,000 109,000
Yield Strength, N/mm² 910 752
Elongation (%) 20 23
Reduction of Area (%) 60 63
Izod Ft./Lbs. 60 63
Izod Joules 81 89
HB of Core 341 311
Hardness of Case HRC 62 60

For more information about our Products and Services, please Contact Us or view our Product Manual.