Hastelloy Bar- Excellent performance in highly oxidizing environments

Hastelloy C22 offers excellent longevity in numerous corrosive environments and boasts a quick lead time. This alloy is used in high temperatures and chloride environments as it resists crevice corrosion, pitting and stress corrosion cracking. Hastelloy C22 has excellent resistance in oxidizing and reducing environments. It has excellent performance when exposed to strong oxidizers such as chlorine, ferric chlorides, cupric chlorides, organic & inorganic hot contaminated solutions, acetic anhydride, formic & acetic acids, seawater and brine solutions.

Products that use acidified solutions are exposed to a high risk of corrosion. 

Hastelloy C22 is widely used in various corrosive environments including phosphoric acids, sulfuric acids in active pharmaceutical ingredients (APIs), chlorides, acetic acids, buffer solutions and any other beauty or health product where contamination due to corrosion is a concern. Hastelloy Bars are widely used in chemical process industry, oil & gas industry and automotive industry. 

The welding characteristicsof the Hastelloy Bar are similar to the austenitic stainless steels and exhibit no special welding problems due to its corrosion resistance. Development and qualification of welding procedure specifications is suggested in order to achieve quality production welds. These procedures are needed for code fabrication and should consider parameters including base & filler materials, joint design, preheat/interpass control, welding process, electrical characteristics and postweld heat treatment requirements. Any modern welding power supply with adequate output and controls can be used with the common fusion welding processes. Welding heat input is controlled in the low to moderate range and wide weave beads are not advised. Stringer bead welding techniques with some electrode/torch manipulation are preferred. 

Hastelloy exhibits both sluggish welding and shallow penetration characteristics. Therefore, care must be taken with respect to joint design and weld bead placement to insure that sound welds with proper weld bead tie-in are achieved. Hastelloy has a tendency to crater crack so grinding of starts and stops is advised. Cleaning is considered an essential aspect of welding of the corrosion-resistant Hastelloy. Contamination by corrosion products, sulfur, greases, lead, oils and other low melting point elements can lead to severe cracking problems.

Welding can be performed on base materials that are in the solution annealed condition. Materials with more than 7% outer Fiber Elongations of cold work should be solution annealed before welding. The welding of materials with huge amounts of residual cold work can lead to cracking in the weld metal and the weld heat affected zone. Various welding processes that are commonly used with Hastelloy are Gas Tungsten Arc Welding, Shielded Metal Arc Welding, Manual and Machine. It is essential to select the welding filler material in the design of a corrosion-resistant welded structure. 

Various types of corrosion-resistant alloys are used at various locations in the same structure. It is also important to select the welding filler materials for dissimilar metal joining applications. There are two methods of welding filler material selection such as selection of overalloyed filler materials and selection of matching filler materials.