Hastelloy C22 Nickel-Chromium-Molybdenum Alloy

Introduction

Super alloys contain a number of elements in a variety of combinations to achieve the desired result. They have good creep and oxidation resistance. They are available in different shapes, and can be used at very high temperatures and mechanical stress, and also where high surface stability is required. Cobalt-based, nickel-based, and iron-based alloys are three types of super alloys. All of these can be used at temperatures above 540°C (1000°F).

Hastelloy(r) C22(r) is a nickel-chromium-molybdenum alloy. It has high resistance corrosion and metallurgical stability. It is not sensitized during heating or welding. The following datasheet gives more details about Hastelloy(r) C22(r).

Chemical Composition

The following table shows the chemical composition of Hastelloy(r) C22(r).

Physical Properties

The physical properties of Hastelloy(r) C22(r) are outlined in the following table.

Mechanical Properties

The mechanical properties of Hastelloy(r) C22(r) are displayed in the following table.

Thermal Properties

The thermal properties of Hastelloy(r)C22(r) are given in the following table.

Other Designations

Other designations that are equivalent to Hastelloy(r) C22(r) include:

• ASTM B366
• ASTM B564
• ASTM B574
• ASTM B575
• ASTM B619
• ASTM B622
• DIN 2.4602

Fabrication and Heat Treatment

Machinability

Hastelloy(r) C22(r) can be machined using high-speed steel tooling. Carbide tools are used for milling or turning. Machining operations can be performed using conventional coolants.

Forming

Hastelloy(r) C22(r) can be easily hot or cold formed followed by heat treatment.

Welding

Except submerged arc welding method, Hastelloy(r) C22(r) can be welded using all other welding methods.

Heat Treatment

Hastelloy(r) C22(r) is heat treated by annealing at 1122°C (2050°F) followed by quenching.

Forging

Hastelloy(r) C22(r) is hot forged at 1149°C (2100°F) followed by heat treatment.

Hot Working

Hastelloy(r) C22(r) has good hot working capacity.

Cold Working

Hastelloy(r) C22(r) has cold working capacity.

Aging

Hastelloy(r) C22(r) is aged at 510 to 1038°C (950 to 1900°F) to increase its tensile strength and hardness. However, V-notch impact strength can be degraded if aging is done above 760°C (1400°F).

Hardening

Hastelloy(r) C22(r) cannot be hardened by heat treatment or cold working.

Applications

Hastelloy(r) C22(r) is used for manufacturing different types of chemical process equipments such as:

• Chlorination systems
• Flue gas scrubbers
• Outlet ducting and stack liners for power plants, pulp and paper bleach plants, sulfur dioxide scrubbers, and weld overlay of less corrosion resistant metals
• Acid production and pickling systems.