Akademik Veri Yönetim Sistemi
4th International Eurasian Conference on Science, Engineering and Technology (EurasianSciEnTech 2022), Ankara, Türkiye, 14 Aralık 2022, ss.117, (Özet Bildiri)
Hot work tool steels are used in hot forming techniques and casting processes. In such applications, the die parts and the material being processed are in direct contact. These working environments cause the surface temperature of the parts forming the die to increase. This heating, which the die parts are exposed to under hot working conditions, causes the die material to not perform the expected performance over time and reduces its working life. The working life of the die is an important factor that determines the die costs. The mechanical properties of the die material such as hardness, toughness and wear resistance determine the working life of the die. The die material and applied heat treatment are two important factors that determine the working life of the die. AISI H13 steel is an easily available popular hot work tool steel with superior properties such as hardenability, toughness and wear resistance. Moreover, the working performance of AISI H13 tool steels can be increased by appropriate heat treatments. Today, H13 steel is a die material that can be subjected to different heat treatments. The heat treatment conventionally applied to H13 steel is quenching + tempering heat treatment. In this study; Quenching and double quenching heat treatments were applied to AISI H13 steel. The austenitization process was carried out at 1030 °C for 30 minutes. Quenching processes were carried out in the form of oil cooling at room temperature. After heat treatment, the microstructures and hardness of the samples were investigated. Hardness measurements were carried out with the Rockwell C (HRC) scale according to the ASTM E18 standard. It has been determined that the microstructure of commercial AISI H13 steel consists of carbide particles of different sizes precipitated in the ferrite matrix. Carbides of different sizes are chromium-rich carbides of the type of M23C6 and M7C3, and vanadium- and molybdenum-rich carbides of the type of MC. The microstructures of the quenched samples were composed of lath martensite and fine spherical carbide particles. The hardness of commercial H13 steel, which was 9 HRC, increased to 45.6 HRC with quenching and decreased to 38.1 HRC with double quenching. The changes in hardness were attributed to the change in the morphology of the martensite phase in the microstructure and the changes in the dimensions of the carbides.