Additive manufacturing of a nickel superalloy: The micromechanics of plasticity and fracture

在提高燃气轮机效率和减少温室气体排放方面已经做出了重大努力。同样，建议使用氢来取代烃类燃料。为了实现这些目标，必须使用先进的制造技术来生产涡轮机的关键部件。激光动力床熔融增材制造（LPBF-AM）是可用于燃气轮机中使用的因科乃尔高温合金3D打印的技术之一。然而，根据LPBF-AM工艺参数的不同，高温合金在3D打印过程中会形成微裂纹，从而降低部件的使用寿命。该项目的目标是确定LPBF-AM工艺参数，以减少此类裂缝，并了解其对局部应力场发展的后续影响。将开发一个先进的数值工具箱来模拟微裂纹的扩展。该项目的结果将有助于更好地估计部件的使用寿命，从而最终提高燃气轮机发电的经济性。

Significant efforts have been made to increase the efficiency of gas turbines and to reduce the emission of greenhouse gases. Likewise, the use of hydrogen is suggested to replace hydro-carbon-based fuels. To achieve these goals, it is mandatory to use advanced manufacturing techniques to produce the key components of turbines. Laser power bed fusion additive manufacturing (LPBF-AM) is one of those techniques that can be used for 3D printing of the Inconel superalloys used in gas turbines. However, depending on the LPBF-AM process parameters, microcracks form during 3D printing of the superalloy, reducing the lifetime of the components. The objectives of this project are to determine LPBF-AM process parameters to reduce such cracks and understand their subsequent effects on the development of localized stress fields. An advanced numerical toolbox will be developed to simulate the propagation of microcracks. The outcome of the project will help provide a better estimation of components lifetimes which will eventually improve the economy of power production from gas turbines.