UNS K93600 (FeNi36, 1.3912) Low Expansion Alloy
K93600 alloy is an iron alloy formulated for controlled thermal expansion. 1.3912 is the EN numeric designation for this material. FeNi36 is the EN chemical designation. And K93600 is the UNS number.
It has the lowest electrical conductivity and can have the highest ductility among low-expansion iron alloys.
The properties of K93600 alloy include three common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare K93600 alloy to: low-expansion iron alloys (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
140 GPa 20 x 106 psi
Elongation at Break
5.0 to 35 %
Shear Strength
320 to 380 MPa 47 to 55 x 103 psi
Tensile Strength: Ultimate (UTS)
480 to 810 MPa 69 to 120 x 103 psi
Tensile Strength: Yield (Proof)
280 to 750 MPa 40 to 110 x 103 psi
Thermal Properties
Curie Temperature
250 °C 480 °F
Maximum Temperature: Mechanical
440 °C 820 °F
Melting Onset (Solidus)
1430 °C 2610 °F
Specific Heat Capacity
520 J/kg-K 0.12 BTU/lb-°F
Thermal Conductivity
13 W/m-K 7.5 BTU/h-ft-°F
Thermal Expansion
7.3 µm/m-K
Other Material Properties
Density
8.1 g/cm3 510 lb/ft3
Electrical Conductivity: Equal Volume
2.2 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.4 % IACS
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
21 to 280 MJ/m3
Resilience: Unit (Modulus of Resilience)
280 to 2050 kJ/m3
Stiffness to Weight: Axial
9.4 points
Stiffness to Weight: Bending
21 points
Strength to Weight: Axial
16 to 28 points
Strength to Weight: Bending
17 to 24 points
Thermal Diffusivity
3.1 mm2/s
Thermal Shock Resistance
34 to 57 points
Followup Questions
Further Reading
Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook vol. 1, ASM International, 1993
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005