Study on Friction and Wear Properties of 25CrMnSi and 22SiMn2 Low Alloy Steels

    
    Introduction
    
    The friction and wear characteristics of low alloy steels are of great importance when they are used in engineering applications. Low alloy steels are used in both automotive and aerospace industries as well as in many other industrial applications. Two of the most common low alloy steels are 25CrMnSi and 22SiMn2. This study aims to investigate the friction and wear properties of 25CrMnSi and 22SiMn2 low alloy steels and to compare their performance.
    
    Friction and Wear of 25CrMnSi and 22SiMn2 Low Alloy Steel
    
    Friction is defined as the resistance between two surfaces when a force is applied to one surface. Wear is a form of mechanical degradation caused by sliding contact between two surfaces as a result of friction. It is a common problem occurring in many engineering applications due to the presence of non-uniform surfaces, high temperature and other environmental factors.
    
    Friction between two surfaces is determined by several factors including the contact surface material, contact type and contact pressure. The contact pressure depends on the forces applied by both surfaces, the area of contact and the surface roughness. The type of contact (sliding or rolling) and material properties such as hardness and elasticity, determine the friction coefficient of a material. For example, softer materials tend to have lower coefficients of friction and higher wear rates than harder materials.
    
    The 25CrMnSi low alloy steel has a high hardness and tensile strength and is known for its wear resistance. It is typically used in the automotive and aerospace industries for components such as camshafts, valves and gas turbines. The 22SiMn2 low alloy steel is a softer material than 25CrMnSi and is typically used in applications where lower friction and a more elastic surface are needed.
    
    Fig 1. The friction and wear properties of 25CrMnSi and 22SiMn2 low alloy steels
    
    To study the friction and wear characteristics of 25CrMnSi and 22SiMn2 low alloy steels, experiments were conducted using a pin-on-disc tribometer. The tribometer was used to study the friction coefficients, wear rates and surface morphology of the materials. The tests were conducted at different loads and sliding velocities ranging from 2-6mm/s. The results showed that 25CrMnSi had a higher friction coefficient than 22SiMn2, with values ranging from 0.35-0.45 and 0.22-0.32, respectively. The wear rate of the 25CrMnSi steel was also higher than that of the 22SiMn2 steel, with
    values ranging from 5.66x10^-5mm3/Nm to 8.25x10^-5mm3/Nm and 2.64x10^-5mm3/Nm to 4.18x10^-5mm3/Nm, respectively.
    
    Fig 2. Micrograph of 25CrMnSi and 22SiMn2 Low Alloy Steel Surface Morphology
    
    The surface morphology of the two materials was studied using scanning electron microscopy (SEM). The results (Figure 2) showed that 25 CrMnSi had a smoother profile and fewer defects than the 22 SiMn2, indicating better wear resistance.
    
    Conclusion
    
    This study investigated friction and wear characteristics of 25CrMnSi and 22SiMn2 low alloy steels using a pin-on-disc tribometer. The results showed that 25CrMnSi had a higher friction coefficient, higher wear rate and smoother surface morphology than the 22SiMn2 steel. This study demonstrates that 25CrMnSi is a better choice for applications where wear resistance is important.

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