Fragmentation mechanism of TiN during stretching of NM500 wear-resistant steel

    
    Introduction
    
    NM500 wear-resistant steel is an increasingly popular material in the production of wear-resistant parts and components due to its outstanding mechanical, physical, and chemical properties. A key component of the wear resistance of this steel is its TiN (titanium nitride) coating, which breaks down during stretching and fracture tests. This mechanism of fracture of the material is known as fragmentation. This article aims to discuss the fragmentation mechanism of TiN during stretching of NM500 wear-resistant steel.
    
    Fragmentation Mechanism
    
    Fragmentation of TiN coating during stretching of NM500 wear-resistant steel is a complex process, given the combination of mechanical, chemical, and environmental factors. The process begins with a uniform layer of TiN coating applied to the surface of the steel. During stretching, the applied pressure causes the TiN coating to crack and fragment into discontinuous pieces. The discontinuity of these fragments is due to the larger deformation that is applied to the TiN coating than to the underlying metal.
    
    The fragmentation then progresses with the cracking and eventual breaking of the metal due to the unrelenting force of the stretching. The TiN coating absorbs the stress energy in the form of sound energy and the process is followed by a rapid release of the compressed energy, causing the TiN coating to fragment further and leading to the eventual destruction of the material (Fig. 1).
    
    Figure 1. Illustration of the fragmentation mechanism of TiN coating during stretching of NM500 wear-resistant steel
    
    The fragmentation depends on the mechanical properties and composition of the TiN coating. The TiN coating is composed of titanium, nitrogen, and oxygen. The size, shape, and bond strength between these atoms affect the fracture toughness of the coating and its susceptibility to fragmentation. The fracture toughness of TiN coating is one of the main factors affecting its fragmentation performance. The fracture toughness evaluates the amount of deformation the TiN coating can endure before it becomes fragile, which ultimately determines its fragmentation performance.
    
    The fragmentation mechanism of TiN also depends on environmental factors, such as humidity and temperature. High humidity or temperature can increase the fragmentation of the coating, while low humidity or temperature can reduce its fragmentation performance.
    
    Conclusion
    
    This article has discussed the fragmentation mechanism of TiN occurring during stretching of NM500 wear-resistant steel. The key factors that influence the fragmentation are the mechanical properties and composition of the coating, as well as environmental factors such as temperature and humidity. Understanding and controlling this fragmentation process is important for producing high-quality wear-resistant steel components.

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