SH-CCT Curve Measurement and Microstructure Analysis of NM360 Steel

NM360 steel is a wear-resistant steel produced in China by Baosteel. It has a good performance and a relatively low price. As a result, it is widely used in a variety of applications, including construction equipment, engineering machinery, hot forging machines, and ship building. It is also used in many automotive applications, such as car frames, bridges, and tank structures. In order to ensure the quality of NM360 steel, a Vickers hardness test, an impact test, a Charpy V-notch impact test, a Bend test and a Rockwell hardness test are performed. In addition, its metallographic properties are evaluated by Vickers microhardness tests and scanning electron microscopy (SEM).
    
The Vickers hardness test is carried out by using a Vickers hardness tester in order to determine the microhardness of the steel. A point indenter is pressed into the sample surface, and the applied pressure is maintained for a pre-set period of time. The resulting indentation is then measured with a light microscope, and its value is then used to determine the sample's RMHS (Rockwell Hardness Scale) value. The RMHS is a measure of the hardness of the material, and it can be used as an indicator of its wear resistance.
    
The impact test is used to measure the impact resistance of a material. In this test, a hammer is dropped from a predetermined height onto the sample. The energy absorbed by the material is then measured and reported as a function of the mass to determine the sample's toughness. This test is used to identify the material's ability to absorb energy and to indicate its resistance to cracking and failure.
    
The Charpy V-notch impact test is used to measure the hardness of ferrous materials. A sample and an anvil are placed in the testing machine and a 0.25 inch steel V-notch is cut at a 0.25 in angle. The impact test is then performed by dropping a pendulum from a fixed height onto the sample. The pendulum strikes the V-notch, and the amount of energy absorbed by the sample indicates the material's resistance to impact.
    
The Bend test is a nondestructive test method used to assess the strength and ductility of a material. It involves bending a sample along its length using a device that applies gradually increasing force until the sample fails in either tension or shear.
    
The Rockwell hardness test is used to measure the hardness of ferrous materials, as well as other metals. In this test a diamond cone or ball indenter is pressed into the sample and then a force is applied. The depth of the indentation is then measured to determine the sample's Rockwell hardness.
    
The metallographic analysis of a material is used to obtain information about its microstructure and its characteristics. This type of analysis is usually performed with a scanning electron microscope (SEM) which makes a three-dimensional picture of the sample. The SEM image is then analysed to assess the grain size and shape, porosity, inclusion and dislocations. This information can be used to identify the mechanical properties such as strength and ductility.
    
The evaluation of the microstructure and mechanical properties of NM360 steel is carried out by performing a set of tests including Vickers hardness testing, impact testing, Charpy V-notch impact testing, bending test, Rockwell hardness testing and SEM. This data helps to determine the microstructure characteristics of the material, which helps in predicting its macroscopic behaviour under different service conditions.
    
The hardness of NM360 steel is typically assessed by plotting a Vickers-CCT curve. This is a graph that plots the hardness number as a function of the applied load. This curve provides a good indicator of the material's behaviour under different loading conditions as it depicts the load-hardness characteristics of the material. The graph can be used to compare different treatments and identify optimal treatment points. It is also used to determine the load bearing capacity of a material.
    
In conclusion, NM360 steel has many excellent properties and is widely used in various industrial applications. To ensure of a quality product, a set of tests need to be conducted. These tests include Vickers hardness testing, impact testing, Charpy V-notch impact testing, bending test, Rockwell hardness testing, and metallographic analysis. The resulting data can then be used to determine the microstructure characteristics and hardness of NM360 steel. This information can then be used to predict its macroscopic behaviour under different service conditions. The Vickers-CCT curve is a useful tool that can be used to assess the hardness and load-bearing capacity of the material.

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