HAVAR

              Havar, a heat treatable cobalt base alloy, provides very high strength at high temperatures, has excellent corrosion resistance and is non-magnetic. Applications have included pressure diaphragms, power springs, gap spacers in magnetic heads, and target foils in nuclear physics.

              Forming cold rolled Havar requires a large radius (90^o Bend - 8 ⋅ thickness), prior to age hardening. Joining can be accomplished using both welding and soldering techniques. The ultimate endurance life is achieved by heat treating the alloy at 1000 ^oF after 80% cold work. The alloy will retain 75% of room temperature strength up to 950 ^oF.

Typical Analysis in Percent:

              Co                        42

              Fe                        bal.

              Cr                        19.5

              Ni                        12.7

              W                         2.7

              Mo                       2.2

              Mn                       1.6

              C                          .2

Typical Physical Properties:

Density: 0.3 lbs/in³

Melting Point: 1480 ^oC

Electrical Resistivity (20 ^oC): 92 microhm ⋅ cm

Thermal Expansion Coefficient (0 ^oC to 50 ^oC): 12.5 x 10^-6/ ^oC

Thermal Conductivity: 13.0 W/m ⋅ K

Magnetic Attraction: None

Typical Mechanical Properties:

                                                                                                                                                                                Cold Rolled

                                                                                            Annealed                         Cold Rolled                     Heat Treated

Ultimate Tensile Strength:                                              140,000 psi                        270,000 psi                        330,000 psi

Yield Strength (.2% Offset):                                            70,000 psi                         250,000 psi                        300,000 psi

Elongation in 2": *                                                                40%                                    1%                                     1%

Hardness:                                                                              RC25                                 RC50                                 RC60

Modulus of Elasticity (Tension):                                   29.5 x 10⁶ psi

*The measured elongation will be less as thickness decreases to .002" and less.