Perković Srđa, Sedmak Aleksandar, Radaković Zoran, Burzić Zijah, Sedmak Simon, Radović Ljubica, Mandić Jovana
Military Technical Institute, 11000 Belgrade, Serbia.
Faculty of Mechanical Engineering, University of Belgrade, 11120 Belgrade, Serbia.
Materials (Basel). 2023 Jun 16;16(12):4432. doi: 10.3390/ma16124432.
The search for alternative materials that can be used for parts of aircraft hydraulic systems has led to the idea of applying S32750 duplex steel for this purpose. This steel is mainly used in the oil and gas, chemical, and food industries. The reasons for this lie in this material's exceptional welding, mechanical, and corrosion resistance properties. In order to verify this material's suitability for aircraft engineering applications, it is necessary to investigate its behaviour at various temperatures since aircrafts operate at a wide range of temperatures. For this reason, the effect of temperatures in the range from +20 °C to -80 °C on impact toughness was investigated in the case of S32750 duplex steel and its welded joints. Testing was performed using an instrumented pendulum to obtain force-time and energy-time diagrams, which allowed for more detailed assessment of the effect of testing temperature on total impact energy and its components of crack initiation energy and crack propagation energy. Testing was performed on standard Charpy specimens extracted from base metal (BM), welded metal (WM), and the heat-affected zone (HAZ). The results of these tests indicated high values of both crack initiation and propagation energies at room temperature for all the zones (BM, WM, and HAZ) and sufficient levels of crack propagation and total impact energies above -50 °C. In addition, fractography was conducted through optical microscopy (OM) and scanning electron microscopy (SEM), indicating ductile vs. cleavage fracture surface areas, which corresponded well with the impact toughness values. The results of this research confirm that the use of S32750 duplex steel in the manufacturing of aircraft hydraulic systems has considerable potential, and future work should confirm this.
寻找可用于飞机液压系统部件的替代材料，引发了将S32750双相钢用于此目的的想法。这种钢主要用于石油和天然气、化工及食品工业。原因在于这种材料具有卓越的焊接、机械和耐腐蚀性能。为验证这种材料是否适用于飞机工程应用，有必要研究其在不同温度下的性能，因为飞机在广泛的温度范围内运行。因此，针对S32750双相钢及其焊接接头，研究了+20℃至 -80℃温度范围内温度对冲击韧性的影响。使用仪器化摆锤进行测试，以获取力 - 时间和能量 - 时间图，从而更详细地评估测试温度对总冲击能量及其裂纹萌生能量和裂纹扩展能量分量的影响。测试在从母材（BM）、焊缝金属（WM）和热影响区（HAZ）提取的标准夏比试样上进行。这些测试结果表明，所有区域（BM、WM和HAZ）在室温下的裂纹萌生和扩展能量值都很高，且在高于 -50℃时裂纹扩展能量和总冲击能量水平充足。此外，通过光学显微镜（OM）和扫描电子显微镜（SEM）进行了断口分析，显示了韧性与解理断裂表面积，这与冲击韧性值吻合良好。这项研究结果证实，在飞机液压系统制造中使用S32750双相钢具有相当大的潜力，未来的工作应予以证实。
