Havar is a precipitation hardening "super-alloy" composed of 41-44% Cobalt, 19-21% Chromium, 12-14% Nickel, 2.3-3.3% of Tungsten, 2-2.8% Molybdenum, 1.35-1.8% Manganese, .17-.23% Carbon, and .02-.08% Beryllium. Havar chemical etching is done for various applications including springs, diaphragms, and target foils for nuclear physics.
It is valued for its retained strength in high temperatures, anti-corrosive properties, and heat treatability. The medical industry prefers Havar due to its biocompatibility and non-magnetic properties.
Fotofab's chemical etching process produces designs that can withstand harsh indoor and outdoor environments. The process uses a strong caustic chemical to cut into unprotected parts of a metal surface to create a design or image formed to your project's specifications.
Fotofab products are made in the USA and distributed worldwide.
Characteristics of Havar
Havar can be hardened by cold work, heat treatment, or both and features:
- Very high mechanical strength
- Corrosion-resistance
- Non-magnetic properties
- High fatigue resistance
- Biocompatibility
- Tensile strength of 960-970 MPa
- Modulus of elasticity of 200-210 GPa
Acid Etching for Havar Applications
Havar foils of various thickness are used in a variety of high temperature applications, including:
- Medical implants
- Springs
- Target foils
- Pressure sensing diaphragms in process control equipment
- Particle beam windows in nuclear physics
Other Factors
- Lends well to heat treating, welding, soldering, and brazing
- Havar will maintain 75% of its strength up to 950 °F, with a melting point of 2696 °F
- Havar outperforms 316L Stainless Steel in resistance to pitting corrosion and crevice corrosion in medical implant environments
- Originally developed in the late 1940s as an alloy for the mainsprings used in watches
- In cold-rolled and aged form, its yield tensile strength is higher than other cobalt-implant alloys
- Also known as UNS R30005
- Havar is frequently used as window materials for high-energy proton beams used in the production of fluorine-18 from oxygen-18 enriched water
- In Green death, havar does not corrode at all at room temperature, starts corroding rapidly (15 mm/year) at 70°C, and reaches a rate of 56 mm/year at its boiling point