DuraKapp™#2 - ASTM B23 Grade 2 Babbitt Engineering Data

By far the most popular Babbitt in bearing refurbishment today is DuraKapp™ #2. Kapp Alloy’s unique processes combine high purity virgin raw materials and our proprietary Precision Microcasting™ process to create the world’s strongest, most ductile Tin-Based Babbitt. DuraKapp™ #2 Babbitt meets or exceeds the specifications for ASTM #2 Babbitt - also known as #2 Babbitt, High Tin Babbitt, and Bearing Babbitt. We stand behind our products with a 100% satisfaction guarantee or your money back.

Typical Applications: Sleeve Bearings, Corrosion resistant and Electro-magnetic Interference (EMI) resistant coatings

Alloy: 89Sn/7.5Sb/3.5Cu / Composition: 89% Tin, 7.5% Antimony, 3.5% Copper

Chemical Composition Limits: Trace Elements (maximum allowable)
88-90 tin, 7-8 antimony, 3-4 copper,

  • Lead (Pb) 0.10
  • Iron (Fe) 0.08
  • Arsenic (As) 0.10
  • Bismuth (Bi) 0.08
  • Zinc (Zn) 0.005
  • Aluminum (Al) 0.005

Mechanical Properties

Tensile Strength (typical); cast at 315oC (600oF) into mold at 150oC (302oF): 87MPa (12,600psi)

Proportional Limit FOR TENSILE PROPERTIES OF CHILL CASTINGS, SEE TABLE 4
cast at 400°C (752°F) into mold at 100°C (212°F): 10.1 MPa (1,460 psi)

Hardness Chill cast; Cast at 315°C (600°F) into mold at 150°C (302°F) - 24 HB.
Cast at 400°C (752°F) into mold at 100°C (212°F) - 22 HB.

Elastic Modulus Tension; Cast at 400°C (750°F) into mold at 100°C (212°F)
= 52 GPa (7.6 x 106 psi)

Table 4 / Mechanical properties of Chill Cast Tin Babbitt - Alloy Grade 2

Temperature Tensile Strength Elongation Reduction
°C °F MPa ksi %(a) in area, %
20 68(b) 77 11.2 18 25
49 120 63 9.2 24 27
100 212(c) 45 6.5 23 28
149 300 28 4.0 32 44
(b) Compressive yield strength, 0.125% set, 42 MPa (6.1 ksi); Compressive strength, 25% set, 103 MPa (14.9 ksi)

(c) Compressive yeild strength, 0.125% set, 21 MPa (3.0 ksi; Compressive strength, 25% set, 60 MPa (8.7 ksi)

Fatigue strength: Chillcast, 33MPa (4.8 ksi) at 2 x 107 cycles, R.R. Moore [type] test

Mass Characteristics: Density: 7.39 mg/m3 (0.267 lbs./in.3)

Thermal Properties: Liquidus temperature: 354°C (669°F)
Solidus temperature: 241°C (466°F)

Fabrication Characteristics: Casting temperature;
Chill castings: 315°C (600°F)

DuraKapp™ #2 MSDS