This work investigated the lubricating and anti-wear properties of several sulfur additives for a nickel-based superalloy–tungsten carbide friction pair. Compared with PAO40 without any active chemical compounds, three kinds could decrease coefficient from 0.2 to 0.1 wear volume by 90%. Sulfurized fatty acid ester had best performance under high temperature heavy load COF below smallest volume....

The application of accurate constitutive relationship in finite element simulation would significantly contribute to accurate simulation results, which play critical roles in process design and optimization. In this investigation, the true stress-strain data of an Inconel 718 superalloy were obtained from a series of isothermal compression tests conducted in a wide temperature range of 1153–135...

Inconel 718 is a Ni-Cr-Fe superalloy which presents excellent mechanical properties at high temperatures, as well as good corrosion resistance and weldability. These characteristics can be optimized with an appropriate control of microstructural features such as grain size and precipitation. Precipitates of different nature can form in these alloys, i.e. γ’’ (a metastable metallic compound Ni3N...

The overall objective of this work has been to develop and evaluate tools for designing against fatigue in gas turbine applications, with special focus on the nickelbased superalloy Inconel 718. The fatigue crack propagation behaviour under high temperature hold times has been studied. Firstly, the main fatigue crack propagation phenomena have been investigated with the aim of setting up a basi...

Dynamic strain aging (DSA) and jerky flow phenomena in the commercial Ni-base alloys Inconel 600 and 690 have been investigated. Tensile tests were performed in the strain rate range of 10 to 10 s at temperatures of 100 – 600 C. No remarkable difference in the DSA behaviour of Inconel 600 and 690 alloys was observed. Tensile properties of the studied alloys in the DSA temperature range, and typ...

In this licentiate thesis the work done in the TURBO POWER project Influence of high temperature hold times on the fatigue life of nickel-based superalloys will be presented. The overall objective of this project is to develop and evaluate tools for designing against fatigue in gas turbine applications, with special focus on the nickel-based superalloy Inconel 718. Firstly, the constitutive beh...