Views:68 Author:Ronsco Publish Time: 2021-06-08 Origin:Ronsco
Hastelloy C is a versatile nickel-chromium-molybdenum tungsten alloy, which has better overall corrosion resistance than other existing nickel-chromium-molybdenum alloys, including Hastelloy C276, Hastelloy C4 alloy and 625 alloy. Hastelloy C alloy has good resistance to pitting corrosion, crevice corrosion and stress corrosion cracking. It has excellent resistance to oxidizing water media, including wet chlorine, nitric acid, or mixed acids of oxidizing acids containing chloride ions.
At the same time, Hastelloy C also has ideal resistance to reducing and oxidizing environments encountered during the process. Relying on this omnipotent performance, it can be used in some troublesome environments, or in a variety of production purpose factories. Hastelloy C alloy has exceptional resistance to various chemical environments, including strong oxidizing substances, such as ferric chloride, copper chloride, chlorine, thermal pollution solutions (organic and inorganic), formic acid, acetic acid, acetic anhydride, sea water and Salt solution, etc.
Hastelloy C has the ability to resist the formation of grain boundary precipitation in the welding heat-affected zone, so that it can be adapted to many chemical process applications in the welding state.
Hastelloy C has a face-centered cubic lattice structure.
Hastelloy C alloy is suitable for various chemical process industries containing oxidizing and reducing media. The higher content of molybdenum and chromium makes the alloy resistant to corrosion by chloride ions, and the element tungsten further improves its corrosion resistance. Hastelloy C is one of the only materials that can resist the corrosion of humid chlorine, hypochlorite and chlorine dioxide solution. The alloy has significant corrosion resistance to high concentration chloride solutions (such as ferric chloride and Copper chloride).
1. Corrosion resistant in sulfuric acid solution of any concentration below 70℃, the corrosion rate is about 0.1mm/a;
2. The corrosion rate in various concentrations of hydrochloric acid at room temperature is not higher than 0.1mm/a; in various concentrations of hydrochloric acid at 65℃, it is also less than 0.5 mm/a. Whether the hydrochloric acid is oxygenated or not has a significant impact on the corrosion resistance. ；
3. The corrosion rate in hydrofluoric acid does not exceed 0.25 mm/a, and the corrosion rate is greater than 0.75 mm/a under the conditions of 55%H3PO4+0.8%HF at the boiling temperature;
4. It is corrosion resistant in dilute nitric acid at room temperature or higher temperature, and the corrosion rate is about 0.1mm/a. It is stable in any concentration of chromic acid, organic acid and other mixed liquids at 60-70℃. It has good corrosion resistance, and the corrosion rate is less than 0.125 mm/a and 0.175 mm/a respectively;
5. It is one of the few materials that can withstand dry and wet chlorine corrosion, and can be used under dry and wet chlorine exchange corrosion conditions;
6. It can withstand high temperature HF gas corrosion, the corrosion rate of HF gas below 550℃ is 0.04 mm/a, and the corrosion rate at 750℃ is 0.16 mm/a.
1. The thermal processing temperature range of Nicrofer 5716 hMoW is 1200℃～950℃, and the cooling method is water cooling or rapid air cooling.
2. In order to ensure the best anti-corrosion performance, heat treatment should be carried out after thermal processing, and the workpiece should be directly added to the heated heat treatment furnace.
1. The work hardening rate is greater than that of austenitic stainless steel, so processing equipment needs to be selected. The workpiece should be in a solution heat treatment state, and there should be intermediate annealing during the cold rolling process.
2. If the cold rolling deformation is greater than 15%, the workpiece needs to be solid solution treated twice.
It is suitable for welding by any traditional welding process, such as tungsten electrode inert gas shielded welding, plasma arc welding, manual sub-arc welding, metal inert gas shielded welding, and molten inert gas shielded welding.
Hastelloy C alloy has been widely used in the chemical and petrochemical fields, such as in components and catalytic systems that contact chloride-containing organics. This material is especially suitable for use in high temperature, mixed with impurities of inorganic and organic acids (such as formic acid and acetic acid), and seawater corrosive environments.
Acetic acid/acetic anhydride
Complex mixed acid
Rolls of electro-galvanized tank
Flue gas cleaner system
Hydrogen fluoride furnace cleaner
Incineration washer system
Nuclear fuel regeneration
Phosphoric acid production
Plate heat exchanger
Selective filtration system
Sulfur dioxide cooling tower
Tubular heat exchanger
21. Surfacing valve