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The Most Sought Properties of ELGILOY Hastelloy Alloy

Extraordinary resistance to HCl and H2SO4 and advanced structural stability

HASTELLOY® B-3® alloy (UNS N10675) displays incredibly high resistance to plain hydrochloric, hydrobromic, and sulfuric acids. In addition, it has drastically enhanced structural stability when compared to previous B-type alloys, resulting in lesser concerns at the time of welding, fabrication, and service.

Similar to other nickel alloys (in the mill annealed condition), it is ductile, tend to be formed and welded, and thwarts stress corrosion cracking in chloride-bearing solutions. Furthermore, it has the ability to withstand fluoride-bearing media and concentrated sulfuric acid, both of which result in damage to zirconium alloys.

Elgiloy Hastelloy

 

HASTELLOY B-3 alloy comes in the form of plates, bars, wires, sheets, strips, billets, pipes, tubes, and coated electrodes. It is actually utilized in many different chemical process industry (CPI) applications, particularly in the construction of reaction vessels for pure, reducing acid service.

Welding & Fabrication

Elgiloy Hastelloy B-3 alloy is extremely amenable to the Gas Metal Arc (GMA/MIG), Gas Tungsten Arc (GTA/TIG) and Shielded Metal Arc (SMA/Stick) welding processes. Fitting filler metals (i.e. solid wires and coated electrodes) can be found for these processes, and welding instruction are given in our Welding and Fabrication Brochure.

Wrought products of HASTELLOY B-3 alloy are available in the Mill Annealed (MA) condition, except if specified. This solution annealing procedure has been created to maximize the alloy’s corrosion resistance and ductility. Following all hot forming operations, the material must be re-annealed to recover optimum properties. The alloy needs to be re-annealed after any cold forming operations that lead to an outer fiber elongation of 7% or higher. The annealing temperature for HASTELLOY B-3 alloy is 1066°C (1950°F), and water quenching is recommended. A hold time at the annealing temperature of 10 to 30 minutes is usually recommended, based on the thickness of the structure.

HASTELLOY B-3® alloy can be hot forged, hot extruded, hot formed, hot rolled and hot upset. Nonetheless, it is more sensitive to strain and strain rates than the austenitic stainless steels, and the hot working temperature range is fairly narrow. For instance, the suggested start temperature for hot forging is 1232°C (2250°F) and the preferred finish temperature is 982°C (1800°F).

Average reductions and consistent re-heating offers the best results, the alloy is stiffer compared to most austenitic stainless steels and more energy is needed in the course of cold forming. Also, HASTELLOY B-3 alloy work hardens much more without difficulty than most austenitic stainless steels, and requires a number of stages of cold work, with intermediate anneals.

Although cold work does not typically affect the resistance of HASTELLOY B-3 alloy to general corrosion, it could actually have an effect on resistance to stress corrosion cracking. For best corrosion performance, so, the re-annealing of cold worked parts (following an outer fiber elongation of 7% or more) is extremely important.

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