S34565 (an austenitic stainless steel) is suitable for seawater desalination plants

First, Overview

S34565 is an austenitic stainless steel belonging to the chromium-nickel-molybdenum series with excellent corrosion resistance and mechanical properties. Its corresponding standard in the United States is ASTM A240/240M-2018. S34565 is widely used in chemical, petroleum, natural gas, marine engineering and other fields, and is favored for its excellent resistance to pitting and crevice corrosion in chloride environments.

Second, chemical composition

The chemical composition of S34565 has a decisive influence on its performance. Its main chemical composition is as follows:

· Carbon (C): ≤0.03%

· Silicon (Si): ≤1.00%

· Manganese (Mn): 5.00-7.00%

· Phosphorus (P): ≤0.030%

· Sulfur (S): ≤0.010%

· Chromium (Cr): 23.0-25.0%

· Nickel (Ni): 16.0-18.0%

· Molybdenum (Mo): 4.0-5.0%

· Nitrogen (N): 0.40-0.60%

· Niobium (Nb): ≤0.10%

The combination of these components makes S34565 perform well in a variety of corrosive environments, especially in chloride environments.

Third, physical properties

The physical properties of S34565 are as follows:

· Density: 7.94 g/cm³

· Elastic modulus: 200 GPa

· Thermal conductivity: 41 W/(m·K)

· Specific heat capacity: 794 J/(kg·K)

· Resistivity: 2.27 μΩ·cm

· Thermal expansion coefficient: 14.5 × 10⁻⁶/°C (20-100°C)

These physical properties give S34565 good stability and thermal conductivity in high temperature and corrosive environments.

Fourth, mechanical properties

The mechanical properties of S34565 are as follows:

· Yield strength (Rp0.2): ≥477 MPa

· Tensile strength (Rm): ≥611 MPa

· Elongation (A): ≥24%

· Sectional shrinkage (Z): ≥42%

· Brinell hardness (HBW): 244

These properties show that S34565 has good strength and toughness and can withstand high mechanical stress.

Fifth, heat treatment process

The heat treatment process of S34565 includes solution treatment, aging treatment and annealing, etc.

· Solution treatment: usually carried out between 1050°C and 1150°C, and then rapidly cooled after heat preservation to obtain a uniform single-phase austenite structure.

· Aging treatment: used to further improve the strength and hardness of the material.

· Annealing: used to eliminate work hardening and internal stress, and improve the plasticity and toughness of the material.

Sixth, Application Fields

S34565 is widely used in the following fields:

· Chemical and oil and gas: used to manufacture high temperature and corrosion resistant equipment and components, such as heat exchangers, reactors, storage tanks, etc.

· Marine engineering: suitable for seawater desalination plants, offshore oil production platforms, etc., because of its excellent corrosion resistance in seawater environment.

· Food processing: due to its good corrosion resistance and hygienic properties, it is often used in food processing equipment and containers.

· Medical devices: used to manufacture medical devices and equipment that need to be corrosion resistant and easy to clean.