Pump shaft material

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There are many materials available for pump shafts, such as 45#, 40Cr, 42CrMo, 2Cr13, 17-4PH, 2507, and so on. The material chosen for the pump shaft is generally determined based on the operating conditions of the water pump. If the water is clean, then conventional 45# steel is sufficient to meet the user’s requirements. Properties of the pump shaft material, 45# steel: 45# is a grade of steel; it is a high-quality carbon structural steel. It corresponds to the Japanese standard S45C, the American standard 1045, and the German standard C45. It is characterized by higher strength and resistance to deformation compared to ordinary A3 steel. 45# steel is widely used in machinery; when untreated: HB≤229 ； Heat treatment: Normalizing ； Impact energy: Aku≥39J ； It has high strength, as well as decent plasticity and toughness. Before tempering, the hardness of 45# steel plate after quenching is greater than HRC55 (and can reach up to HRC62 in some cases), which is considered acceptable. Through heat treatment followed by tempering, the hardness can be reduced to the range of HRC42-46; this ensures both good mechanical properties and the required surface hardness. It is used for manufacturing small-section components that are subject to high loads and large-sized components that experience lower stresses, as well as parts that require surface quenching but do not need high strength in their core, such as shafts, pins, guide posts, and hand pointers. If the user has requirements regarding the material’s impact resistance, then we can choose 40Cr. Material properties of the pump shaft: 40Cr. 40Cr is a standard steel grade according to China’s GB standards, and it is one of the steels most widely used in the machinery manufacturing industry. After quenching and tempering, it exhibits good comprehensive mechanical properties, excellent low-temperature impact toughness, and low notch sensitivity. Steel has good hardenability, making it suitable for manufacturing medium-sized plastic molds. The hardness of 40Cr after quenching and tempering is approximately between 32-36 HRC, which is equivalent to around 301-340 HB. Medium-carbon quenched and tempered steel, cold heading die steel. This steel has a moderate price, is easy to process, and can acquire certain toughness, ductility, and wear resistance after appropriate heat treatment. Normalizing can promote microstructure refinement, achieve an optimal state, and improve the machinability of the blank. When tempered at temperatures of 550–570°C, this steel exhibits excellent overall mechanical properties. The hardenability of this steel is higher than that of 45# steel, making it suitable for surface hardening treatments such as high-frequency quenching and flame quenching. After quenching and tempering, this steel is used to manufacture mechanical parts that are subjected to moderate loads and operate at moderate speeds, such as automobile steering knuckles and rear axles, as well as gears, shafts, worms, spline shafts, and thimble sleeves in machine tools ； After quenching and medium-temperature tempering, it is used to manufacture parts that are subject to high loads, impacts, and operate at moderate speeds, such as gears, spindles, oil pump rotors, sliders, rings, etc ； After quenching and low-temperature tempering, it is used to manufacture parts that are subject to heavy loads and low impacts, require wear resistance, and have a solid thickness in the cross-section of less than 25 mm, such as worms, spindles, shafts, and rings ； After quenching and tempering as well as high-frequency surface hardening, it is used to manufacture parts with high surface hardness and wear resistance while withstanding minimal impact, such as gears, sleeves, shafts, spindles, crankshafts, mandrels, pins, connecting rods, screws, nuts, intake valves, etc. Furthermore, this steel is also suitable for manufacturing various transmission components that are subjected to carbonitriding treatment, such as gears and shafts with large diameters and good low-temperature toughness. Material of multi-stage pump shaft: 40Cr. Shaft components are one of the typical components that are commonly found in machines. It is mainly used to support transmission components, transmit torque, and bear loads. Shaft components are rotating parts whose length is greater than their diameter; they generally consist of the outer cylindrical surface, conical surface, inner hole, threads, and corresponding end faces of concentric shafts. Depending on their structural shape, shaft components can be divided into solid shafts, stepped shafts, hollow shafts, and crankshafts, etc. Differences between 45# steel and 40Cr, 42CrMo: 45# steel is a high-quality carbon structural steel with a carbon content of 0.42–0.50%, a tensile strength of 610 MPa, and a yield strength of 360 MPa ； Used for general shaft components. 40Cr is an alloy structural steel with a carbon content of 0.37–0.45% and a chromium content of 0.8–1%; its tensile strength is 1000 MPa and its yield strength is 800 MPa ； Used for shafts in components subjected to high loads. 42CrMo is an alloy structural steel with a carbon content of 0.38–0.45%, 0.9–1.2% chromium, and 0.15–0.25% molybdenum. Its tensile strength is 1100 MPa, and its yield strength is 950 MPa. Components with high loads and high reliability requirements are used. For materials that are generally corrosive, 2Cr13 can be chosen. The properties of this material are as follows: 2Cr13 is a martensitic stainless steel; it is magnetic, has high hardness, and requires preheating during welding. Austenitic stainless steel electrodes used for welding Q235 do not require preheating; options such as A302 and A307 work well. During welding, control the weld dilution rate; avoid swaying while welding, and use a lower current. Application range of 2Cr13 stainless steel: 2Cr13 stainless steel has high hardness in its quenched state and good corrosion resistance. Many of them are used for making cutting tools; they are \"cutting tool grade\" martensitic steels. They are also used in surgical instruments, similar to earlier types of stainless steels such as Breslauer high-chromium steel. Additionally, they are employed in turbine blades and other applications, giving them a wide range of uses. Mechanical properties of 2Cr13 stainless steel: Tensile strength σb (MPa): after quenching and tempering, ≥635 ； Conditional yield strength σ0.2 (MPa): Quenched and tempered, ≥440 ； Elongation δ5 (%): Quenched and tempered, ≥20 ； Section shrinkage rate ψ (%): Quenched and tempered, ≥50 ； Impact energy Aku2(J): Quenched and tempered, ≥63 ； Hardness: Annealed, ≤223HB; Quenched and tempered, >192HB ； Heat treatment specifications and microstructure of 2Cr13 stainless steel: Heat treatment specifications: 1) Annealing, slow cooling at 800–900°C or rapid cooling at about 750°C ； 2) Quenching, oil cooling at 920～980℃ ； 3) Tempering, rapid cooling at 600～750℃. Metallographic structure: The structural characteristic is martensitic. Based on the above overview and other considerations, there is no particularly excellent material for shafts; rather, the most suitable material must be chosen depending on the operating conditions.