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Heat Treatments and Surface Hardening of Small Weapon Components
Published in Jose Martin Herrera Ramirez, Luis Adrian Zuñiga Aviles, Designing Small Weapons, 2022
Jose Martin Herrera Ramirez, Luis Adrian Zuñiga Aviles
Nitriding is a process in which nitrogen diffuses into the surface of a steel to form a hard case. It consists of subjecting a workpiece to the action of a nitrogenous medium at temperatures well below A1 line (Figure 8.1) during a long soaking time, which may be up to 1–2 days. Because the heating does not reach the austenitizing temperature, quenching is not required. Therefore, nitriding results in minimum distortion of the workpiece.
Gear Materials
Published in Stephen P. Radzevich, Dudley's Handbook of Practical Gear Design and Manufacture, 2021
Nitriding is a case-hardening process in which the hardening agents are nitrides formed in the surface layers of steel through the absorption of nitrogen from a nitrogenous medium, usually dissociated ammonia gas.
Heat Treatment of Cast Iron
Published in Bankim Chandra Ray, Rajesh Kumar Prusty, Deepak Nayak, Phase Transformations and Heat Treatments of Steels, 2020
Bankim Chandra Ray, Rajesh Kumar Prusty, Deepak Nayak
As already discussed, nitriding is a type of case hardening process that involves the diffusion process of nitrogen at a high temperature in the range of 550°C–650°C in the presence of an ammonia atmosphere. The treatment, in this case, leads to the formation of a thin layer with a high hardness value of 1100 VPN. The presence of alloying elements can increase the extent of case hardening. The nitriding process is done to improve the hardness, wear resistance, and corrosion resistance.
Surface and bulk modification techniques to mitigate silt erosion in hydro turbines: a review of techniques and parameters
Published in Surface Engineering, 2022
Nitriding is a thermochemical treatment in which nascent nitrogen is diffused on the surface to create a case-hardened surface. Nitriding has been practiced by plasma, gas, and salt-bath methods in the literature. Allenstein and co-researchers conducted low-temperature plasma nitriding of 13-4 MSS at 350°C for 6, 12, and 24 h nitriding times [86]. After nitriding, they found the formation of nitrogen-expanded austenite from the martensite matrix which improved the hardness of the nitrided surface. The improved hardness enhanced the erosion performance of nitrided steel. Guru Prakash and Nath performed low-temperature salt-bath nitriding on 13-4 MSS at 450 and 500°C for 10 h [87]. The microstructure of the nitrided steel comprised the expanded martensite and brittle CrN phases in the nitride samples at 450 and 500°C, respectively. The nanohardness and the elastic modulus increased considerably for the nitrided samples. The sample nitrided at 450°C underwent lesser material loss during the slurry erosion while the sample nitrided at 500°C underwent higher material loss due to the formation of the brittle CrN phase.
Improvement of stamping performance of H13 steel by compound-layer free plasma nitriding
Published in Surface Engineering, 2020
Tiantian Peng, Xiaobing Zhao, Yao Chen, Lei Tang, Kunxia Wei, Jing Hu
The indentation characteristics after microhardness tests can be used to evaluate the impact toughness of the nitriding layer by checking if microcrack exists around the indentation. Figure 3 shows the indentation morphology of samples nitriding by different processes. It can be seen that the obvious cracks appear around the indentation of sample nitrided at 510°C and 490°C under any testing load. However, no crack exists around the indentation of sample nitrided at 470°C, which implies that the impact toughness is evidently increased, since no compound layer is formed on the surface as shown in Figure 1.
High-temperature tribological behaviours of H13 hot work mould steel by low-temperature plasma nitriding process
Published in Canadian Metallurgical Quarterly, 2023
Wang Wenchang, Zhao Wen, Kong Dejun
The surface hardness of the substrate and nitrided layer is listed in Table 2. The average hardness of the nitrided layer was 1145 ± 25 HV0.5, higher than 518 ± 34 HV0.5 of the substrate, indicating that the nitriding process significantly enhanced the hardness of the substrate.