What is Hastelloy C22?

Hastelloy C22, also known as Alloy C-22, is a versatile austenitic nickel-chromium-molybdenum-tungsten alloy with better overall corrosion resistance compared to other nickel-chromium-molybdenum alloys, including alloy C-276, alloy C4 and alloy 625. Here is the Hastelloy c22 datasheet.

Specification

The high chromium content in hastelloy C22 chemical composition provides good resistance to oxidizing media while the molybdenum and tungsten content give good resistance to reducing media. This combination of corrosion resistance makes Alloy 22 particularly useful in applications where mixed acids are present. 

Chemical Composition

Corrosion Resistance

Hastelloy C-22 has an enhanced resistance to pitting, crevice corrosion and stress corrosion cracking because of hastelloy C22 chemical resistance. This nickel steel alloy also has excellent resistance to oxidizing aqueous media including wet chlorine and mixtures containing nitric acid or oxidizing acids with chlorine ions. 

Hastelloy C-22 has resistance to oxidizing acid chlorides, wet chlorine, formic and acetic acids, ferric and cupric chlorides, sea water, brine and many mixed or contaminated chemical solutions, both organic and inorganic. Alloy C276 belongs to the same group as C22, however, the difference between hastelloy C22 and C276 is that C22 offers more corrosion resistance than C276. Hence, among hastelloy C22 vs C276, C22 is the better version.

This nickel hastelloy C22 properties also offers optimum resistance to environments where reducing and oxidizing conditions are encountered in process streams. Alloy C22 Hastelloy should not be used in service temperatures above 1250° F due to the formation of detrimental phases which form above this temperature.

At elevated temperatures, the high chromium level of Inconel Alloy 22 helps it resist oxidation, carburization, and sulfidation. Since it is nickel-base, hastelloy C22 material properties resist high temperature attack by halides (e.g., chlorides and fluorides). With these attributes, the alloy is widely used to protect hastelloy C22 tube and other components in coal-fired and waste-to-energy boilers. Hastelloy C22 ASTM B366 is the Hastelloy C22 equivalent. The hastelloy C22 price is higher than its other equivalents. 

Fabrication and Heat Treatment

Since hastelloy C22 density is good, it can be hot forged, hot rolled, hot upset, hot extruded, and hot formed followed by heat treatment. The hot working temperature range is quite narrow. For example, the recommended start temperature for hot forging is 1232°C (2250°F) and the recommended finish temperature is 954°C (1750°F). 

Physical Properties

Although ductile enough to be formed by cold working, intermediate annealing may be necessary due to work hardening. Annealing can be performed at a temperature range between 2020-2150° F followed by a rapid quench. 

With the fabrication of Alloy C22, items like hastelloy c22 pipe, hastelloy c22 bar, hastelloy c22 plate, hastelloy c22 rod, hastelloy c22 sheet, hastelloy c22 pipe fittings and hastelloy c22 round bar are produced. Various hastelloy c22 suppliers like hastelloy c22 pipe suppliers and hastelloy c22 plate suppliers offer these items. The hastelloy C22 price per kg for these equipment varies from supplier to supplier. 

Weldability

INCONEL alloy 22 is readily fabricated by standard procedures for nickel alloys. Hastelloy C22 welding can be done by gas tungsten-arc, gas metal-arc, and shielded metal-arc processes. Alloy C22 is readily weldable when compared as alloy C22 vs hastelloy C276. The density of hastelloy C22 also plays a major role in its welding. 

Alloy C22 welding products are also used for weld overlay of boiler tubes, waterwalls, and hardware in electric power generation boilers fired by high sulfur coal or oil and waste-to-energy incineration systems fired by municipal and industrial waste. 

Application

Hastelloy C22 is widely used in the chemical field and petrifaction field, such as in the element of chloride organic and catalyze system. This material especially suits high temperature environments, impure inorganic acid and organic acid (such as formic acid and acetic acid), sea-water corrosion environments. 

• Nuclear fuel regeneration
• Pesticide manufacture
• Phosphoric acid manufacture
• Acid cleaning system
• Plate heat exchanger
• Selectivity filter system
• Sulfur dioxide cooling tower
• Sulfonating system
• Tubing heat exchanger
• Resurfacing welding valve
• Flue gas scrubber components
• Nuclear fuel reprocessing
• Sour gas production components
• Pesticide production components

NOTE:  Hastelloy C-22 is a registered trademark of Haynes International Inc.