How Crucial Is Choosing the Right Material for Forged Shaft Forgings?
In manufacturing application scenarios in various fields, shafts are one of the key components that support the operation of equipment. The material selection is directly related to the life, performance and safety of the equipment. However, there are many types of materials on the market. The material selection of forged shaft forgings is a complex and important decision-making process that requires comprehensive consideration of multiple factors. So, how should the material of forged shaft forgings be selected? This article will share the material guide provided by Songjie.
I. Alloy Structural Steel
At Songjie, the customization of forged shaft forgings using alloy structural steel is the most common practice.
- Advantages: Alloy structural steel is developed by adding alloying elements (such as chromium, nickel, and molybdenum) to carbon structural steel, which significantly enhances the performance of alloy shafts—including strength, hardness, toughness, hardenability, fatigue resistance, and wear resistance. This allows them to operate under harsher working conditions, adapting to high-load and high-speed environments.
- Common Alloy Steel Grades: 40Cr, 42CrMo, 20CrMnTi, 35CrMo, 4340, 4140, 5120, 8620, 30CrMo, etc.
- Applications: Critical shaft components in automotive, machine tool, and construction machinery industries, such as automobile transmission shafts, machine tool spindles, crane drive shafts, and generator rotor shafts.
- Songjie’s Practical Case: An automobile manufacturer required us to forge the input shaft of an automobile transmission using 20CrMnTi steel. After carburizing and quenching, the surface hardness reaches HRC58-62, while the core hardness is HRC30-40. This ensures the shaft can withstand impact loads in the transmission, maintains surface wear resistance, and retains internal toughness, making the transmission run stably and reliably with a service life extended by over 30%.
II. Stainless Steel
In environments requiring corrosion resistance, stainless steel is the ideal choice for forged shaft forgings.
- Advantages: It offers excellent corrosion resistance, oxidation resistance, heat resistance, as well as sufficient strength and toughness. Additionally, it has strong aesthetic appeal.
- Common Stainless Steel Grades: 304, 316, 17-4PH, 420, 316L, 1Cr18Ni9Ti, etc.
- Applications: Stainless steel shaft forgings are commonly used in industries such as chemical engineering, food processing, pharmaceuticals, and marine engineering. Typical applications include agitator shafts for chemical equipment, drive shafts for food processing machinery, chemical pump shafts, and marine shafts.
- Songjie’s Practical Case: A reactor agitator shaft for a chemical plant in Brazil was forged using 316 stainless steel. Despite long-term exposure to acid and alkali solutions, no corrosion occurred. This ensured the reactor’s long-term stable operation, significantly reduced equipment maintenance costs, and extended the service life by more than 3 times.
III. Tool Steel
This type of steel can effectively resist friction, wear, and surface scratches, extending the service life of shaft components. Moreover, it exhibits minimal deformation after heat treatment, making it a preferred material for manufacturing shaft products.
- Advantages: High hardness, high wear resistance, strong toughness, and excellent hardenability, among others.
- Common Tool Steel Grades: 1.2379, D2, Cr12MoV, 5CrNiMo, W18Cr4V, 9SiCr, L6, etc.
- Applications: Forged shaft forgings are particularly suitable for working conditions involving high loads, frictional wear, or complex stresses. They are mainly used in industries such as machine tool manufacturing, engineering machinery, precision instruments, and mold equipment. Typical applications include machine tool feed shafts, shearing machine shafts, crusher drive shafts, and guide shafts in precision stamping dies.
- Songjie’s Practical Case: A precision machine tool manufacturer from Europe sent us drawings to customize high-precision grinding machine spindles. We ensured the spindles featured high hardness, wear resistance, and rotational accuracy, enabling the grinding machine to process high-precision parts and meet the requirements of precision manufacturing.
IV. High-Temperature Alloy Steel
High-temperature alloy steel is a high-end material for manufacturing forged shaft forgings. It performs excellently under extremely complex working conditions and can meet the requirements of some special fields.
- Advantages: Outstanding high-temperature strength, oxidation resistance, fatigue resistance, and corrosion resistance, etc.
- Common High-Temperature Alloy Grades: GH4169 (Inconel 718), Cr11MoV, GH536, Inconel 601, etc.
- Applications: They are widely used in aerospace, nuclear industry, energy, petrochemical and other fields, such as aero-engine turbine shafts, steam turbine main shafts, gas turbine rotors, etc.
- Songjie’s Practical Case: In an aviation project from an Australian customer, they purchased the GH4698 alloy turbine disk journal forgings manufactured by us. GH4698 is a nickel-based age precipitation-strengthened high-temperature alloy, which has high creep strength and good comprehensive performance in the temperature range of 500-800℃. Therefore, the forging can operate continuously at high temperatures for 100,000 hours with stable performance, providing reliable support.
Conclusion
The selection of materials for forged shaft forgings is a process that requires careful consideration. The performance differences of different materials, their common grades, and their application scenarios all need to be carefully evaluated. In addition to the above materials, Songjie also supports the manufacturing of forged shafts using aluminum alloys, titanium alloys, bearing steels, carbon steels, and other materials, providing a variety of high-quality forged shafts. Moreover, our steel shaft forgings possess various excellent properties, enabling them to meet the requirements of different application scenarios.