Shouyi Sun

Northwestern Polytechnical University | NWPU · School of Mechanical Engineering

Ni-based superalloys are usually utilized in hot-section components of gas-turbines and aeroengines, which are prone to fatigue failure under the rotational and vibrant working condition. The anisotropic mechanical properties of laser additive manufactured (LAMed) Ni-based superalloy is evident due to its unique microstructure of directional grown...

An amorphous carbon (a-C) film shows substantial potential for friction and wear reduction. In this work, the robust superlubricity state with a coefficient of friction of 0.002 at the maximal pressure of 1.15 GPa was realized when lithium citrate (LC) was applied as the lubricating additive in ethylene glycol (EG) to lubricate the Si3N4/a-C fricti...

The energy input highly determines the microstructure, texture and tensile properties of the laser directed energy deposited (L-DEDed) Ni-based superalloy. This study adopted three levels of energy input from low, medium to high evaluated by the areal energy density to fabricate GH4169 alloy. Results show that a synchronously enhanced strength-duct...

A nanochannel, based on CF 3 to break water clusters, achieves a record output power density of 4.10 W m ⁻² among clay generators.

The hot-section components are prone to fatigue failure due to severe working condition of high rotational speed and high cyclic load at high temperature. This study investigates the fatigue behavior of GH4169 Ni-based su- peralloy at 650 ◦ C fabricated by laser directed energy deposition (L-DED) and proposes an improved high- temperature fatigue...

The tribological behavior of a nickel-based single crystal superalloy treated by shot-peening has been investigated. Friction tests under three normal loads and three temperatures were carried out based on the ball-on-disk configuration. The results showed that coefficient of friction (COF) and wear rate of the shot-peened nickel-based single cryst...

In this work, the macroscopic superlubricity with an extremely low coefficient of friction (COF) of 0.004 was achieved on the friction pair of the steel/amorphous carbon (a-C) film with the lubrication of 3-hydroxypropionic acid aqueous solution (3HPA(aq)). The excellent lubrication performance was ascribed to the solid-liquid synergistic lubricati...

An arc tenon/mortise assembly is designed and optimized based on the free-form deformation (FFD) technique. Traditional tenon connection structure with planar-to-planar contact is prone to fretting fatigue due to the action of centrifugal loading and vibration. Therefore, a novel tenon connection structure with arc-to-arc contact is developed and i...

The tribological behavior of a nickel-based single crystal (NBSC) superalloy treated by shot-peening has been investigated. Friction tests under three normal loads and three temperatures were carried out based on the ball-on-disc configuration. The results showed that coefficient of friction (COF) and wear rate of the shot-peened superalloy at room...

The fretting fatigue behaviors of a nickel-based single crystal superalloy in contact with a powder metallurgy alloy at 600 °C are investigated. Fretting fatigue tests are conducted by using a novel high temperature fretting fatigue test apparatus that is developed, and the crystal plasticity finite element method is used to analyze the contact str...

Formation of raft structure and widening of γ matrix width are usually observed in the nickel-based single crystal superalloys at high temperature loading conditions. But the effect of this rafting behavior on the mechanical property is still ambiguous until now. In the present study, a visco-plasticity phase-field model with the classical flow the...

A novel high temperature fretting fatigue test apparatus was developed to investigate the fretting fatigue mechanism of Nickel-based single crystal (NBSX) superalloys at elevated temperature. The fretting fatigue tests were carried out under 5 loading conditions at 600°C. Results showed that the fretting fatigue life decreased with the increase of...

The twin-web disk holds big promise for increasing efficiency of the aircraft engine. Its reliability-based multidisciplinary design optimization involves several disciplines including fluid mechanics, heat transfer, structural strength, and vibration. The solution to this optimization problem requires three-loop calculations including loops for op...

The nickel-based single crystal (NBSC) superalloy has been widely used in aero engines, gas turbines, and other power plants due to its excellent high-temperature performance. During the working process, wear often occurs on the contact surface of the NBSC superalloy, which will promote crack nucleation and reduce its working life. In this work, th...

Centrifugal compressor is widely used in turbochargers in which the aerodynamic performance and strength are invariable among the important design objectives. As high pressure ratio centrifugal compressor develops, the interaction between multiple disciplines should be involved in the preliminary design process. A strength prediction method was pre...

Fretting fatigue failure behavior of DD6 Nickel-based single crystal superalloy dovetail attachment at 600 °C has been investigated. The contact surface material is oxidized at high temperature and the oxides are compacted on the contact surface. The contact surface is delaminated and many pits are formed, which result in stress concentration near...

On basis of free-form deformation method, a parameterized mesh deformation to morph coordinately fluid analysis mesh and structure analysis mesh was proposed, and reliability-based multidisciplinary design optimization of single turbine stage with parameterized mesh deformation was introduced. According to the extended feature of blade in spanwise...

A parameterized Free-Form Deformation (FFD) method with mapping design parameters for aerodynamic shape optimization of turbine is developed. According to the expanded feature of aerodynamic analysis grid in the spanwise direction, 3D control volume for mesh deformation of aerodynamic analysis grid is decomposed into a number of 2D control planes a...

At present, advanced gas turbine are designed to work at increasingly higher turbine inlet temperatures (TIT) to obtain higher thermal efficiency and power. TIT of modern aircraft engine has exceeded temperature limit of high-temperature alloys application over 600C°. So turbine blade has to be cooled in order to work at an acceptable temperature e...