Alloy 59

Material grade: Alloy 59 nickel-based alloy

US grade: UNS N06059

German grade: 2.4605

1. Overview of Alloy 59 (N06059) nickel-based alloy:

Alloy 59 (N06059) nickel-based alloy is a nickel-chromium-molybdenum alloy with extremely low silicon and carbon content. Has excellent corrosion resistance and extremely high mechanical strength. Alloy 59 (N06059) nickel-based alloy tool also has the following characteristics:

1. Excellent resistance to pitting corrosion, crevice corrosion and stress corrosion cracking caused by chloride.

2. Excellent corrosion resistance to inorganic acids, such as nitric acid, phosphoric acid, sulfuric acid and hydrochloric acid, especially the mixture of sulfuric acid and hydrochloric acid.

3. Excellent resistance to corrosion by various inorganic acid mixed solutions.

4. It has good corrosion resistance in hydrochloric acid solutions of various concentrations up to 40℃ (104℉).

5. It has good processability and weldability, and no sensitivity to cracking after welding.

6. Manufacturing certification of pressure vessels with wall temperatures between -196 and 450°C.

7. It is certified by the NACE standard of the American Society of Corrosion Engineers (MR-01-75) and meets the highest standard level VII for use in sour gas environments.

2. Chemical composition of Alloy 59 (N06059) nickel-based alloy: see Table-1:

3. Mechanical properties of Alloy 59 (N06059) nickel-based alloy:

1. Alloy 59 (N06059) nickel-based alloy density: 8.6g/cm3

2. Alloy 59 (N06059) nickel-based alloy melting point: 1310-1360℃

3. Alloy 59 (N06059) nickel-based alloy tensile strength: σ0.2≥690Mpa,

4. Alloy 59 (N06059) nickel-based alloy yield strength: σb≥340Mpa,

5. Alloy 59(N06059) Nickel-based alloy elongation: δ≥40,

IV. Alloy 59(N06059) Nickel-based alloy corrosion resistance:

1. Alloy 59(N06059) The carbon and silicon content of nickel-based alloys is extremely low, and there is no tendency for impurity phases to precipitate during hot processing and welding. Therefore, they are suitable for various chemical process industries containing oxidizing and reducing media. The higher molybdenum and chromium content makes the alloy resistant to chloride ions.

2. Alloy 59 (N06059) Nickel-based alloy In most standard corrosion tests in oxidizing environments, the performance of Nicrofer 5923 hMo is higher than that of other Ni-Cr-Mo stainless steels. The corrosion rate of Alloy 59 (N06059) nickel-based alloy in some reducing environments (such as boiling 10 sulfuric acid) is more than three times lower than that of conventional Ni-Cr-Mo stainless steel. It is also suitable for chemical process industries in reducing environments. Alloy 59 (N06059) nickel-based alloy has excellent corrosion resistance in hydrochloric acid.

3. Alloy 59 (N06059) nickel-based alloy material can have the best corrosion resistance only when it has a suitable metallographic state and a pure crystal structure.

5. Processing and heat treatment of Alloy 59 (N06059) nickel-based alloy:

Alloy 59 (N06059) nickel-based alloy has good cold and hot processing and machining properties.

1. Heating:

(1). The workpiece should always be kept clean and pollution-free before and during heat treatment.

(2) During the heat treatment process, do not come into contact with sulfur, phosphorus, lead and other low melting point metals, otherwise the performance of Alloy 59 (N06059) alloy will be damaged. Pay attention to remove marking paint, temperature indicating paint, etc. , colored crayons, lubricating oil, fuel and other contaminants.

(3). The lower the sulfur content in the fuel, the better. The sulfur content in natural gas should be less than 0.1, and the sulfur content in heavy oil should be less than 0.5.

(4). Considering the need for temperature control and cleanliness, it is best to perform heat treatment in a vacuum furnace or gas protection furnace.

(5) Heating can also be done in a box furnace or gas furnace, but the furnace gas must be clean and neutral to slightly oxidizing, and the furnace gas should be avoided between oxidizing and reducing properties. fluctuation, the heating flame cannot burn directly to the workpiece.

2. Hot processing:

(1) The hot processing temperature range of Alloy 59 (N06059) alloy is 1180℃~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 heat processing, and the workpiece should be directly added to the heated heat treatment furnace.

3. Cold working:

(1) The work hardening rate of Alloy 59 (N06059) alloy is greater than that of austenitic stainless steel, so processing equipment needs to be selected. The workpiece should be in an annealed 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 solution treated.

4. Heat treatment:

(1). The solution treatment temperature range of Alloy 59 (N06059) alloy is 1100℃~1180℃.

(2). For materials with a thickness less than 1.5mm, it is recommended to use water quenching or rapid air cooling to ensure the best corrosion resistance.

(3) During all heat treatment processes, the workpiece should be directly added to the heated heat treatment furnace, and the workpiece must be kept clean.

5. Scale removal:

(1) The surface oxide of Alloy 59 (N06059) alloy and the welding slag around the weld have stronger adhesion than stainless steel, so it is recommended Use a fine-grain abrasive belt or fine-grain grinding wheel for sanding.

(2) Careful grinding or salt bath pretreatment must be carried out to break up the oxide film before pickling with HNO3/HF mixed acid at appropriate time and temperature.

6. Machining: Alloy 59 (N06059) alloy should be machined after heat treatment. Due to the work hardening of the material, it is advisable to use a lower cutting speed and weight than when processing low-alloy standard austenitic stainless steel. Only when the tool is advanced for processing can it go under the cold-hardened surface layer.

7. Welding recommendations: When welding nickel-based materials, the following procedures should be followed:

(1). Work site The work site should be separated or separated from the carbon steel The processing areas should be far enough apart, kept as clean as possible, equipped with partitions and avoid ventilation between the two areas.

(2) Work clothes and auxiliary supplies Clean fine-grained leather gloves and clean work clothes should be worn.

(3) Tools and machinery and equipment should have special tools for nickel-based alloy and nickel-chromium steel. Wire brushes should be made of stainless steel. Machinery and equipment such as shears, punches, rolling mills, etc. should be covered Cover with felt, cardboard or plastic paper to prevent iron and carbon metal from falling on the surface of the machine and causing the processing materials to stick, causing corrosion.

8. Cleaning: The materials to be welded should be in a solid solution state, remove scale, oil stains and various markings, and use acetone to clean the base metal and filler alloy (such as welding rods) in the welding area. , please note that trichlorethylene TRI, perchlorethylene PER and tetrachloride TETRA cannot be used.

9. Edge preparation: It is best to use machining, such as turning, milling, planing, or plasma cutting. If the latter is used, the cutting edge (welding surface) must be ground clean and smooth. Hot fine grinding.

10. Groove angle: Compared with carbon steel, the physical properties of nickel-based alloys and special stainless steels are mainly low thermal conductivity and high expansion coefficient. These characteristics must be achieved in the welding groove. It should be considered during preparation, including widening the bottom gap (1~3mm). At the same time, due to the viscosity of the molten metal, a larger groove angle (60~70°) should be used during butt welding to offset the shrinkage of the material.

11. Arc starting: The arc should be started in the welding area of ??the workpiece, that is, the arc is started on the welding surface to prevent the arc starting point from causing corrosion.

12. Welding process: Alloy 59 (N06059) alloy can be welded with the same material or other metals, and is suitable for welding with any traditional welding process, such as tungsten electrode inert gas shielded welding, plasma arc welding, manual sub-welding For arc welding, metal arc welding, and melting arc welding, pulse sub-arc welding technology is preferred. When using manual arc welding, it is recommended to use a mixed shielding gas consisting of Ar He H2 CO2.

13. Filler metal: For gas shielded welding, it is recommended to use electrodes with the same chemical composition as the base material. Commonly used welding wire: ERNiCrMo-13 Coated welding rod: ENiCrMo-13.

6. Application scope of Alloy 59 (N06059) nickel-based alloy:

Alloy 59 (N06059) alloy has a wide range of applications in the fields of chemistry, petrochemicals, energy manufacturing and pollution control. Typical applications are as follows:

1. Especially when using acidic chloride catalysts. 2. Digesters and bleaching equipment in the pulp and paper industry. 3. Scrubbers, reheaters, throttle valves, wet steam fans and agitators in FGD and IG systems. 4. Equipment and components operating in sour gas environments. 5. Reactor for acetic acid and acetic anhydride products. 6. Sulfuric acid condenser.