The input shaft of gearbox usually bears a cyclic variation of torque, which may lead to the risk of experiencing a fatigue fracture. To evaluate the fatigue life accurately and identify the weak parts, the ANSYS is used to simulate the torsional fatigue of the input shaft for the gearbox, and the fatigue life of the weak part is obtained, which is then tested and verified by the torsional fatigue testing in the MTS torsional fatigue test rig. The test results show that the maximum difference is 14% between the calculated life and the testing results, indicating that the simulation value can reflect the actual fatigue life accurately. Notably, the cracks appear in the large oil holes, and its life is mainly concentrated in the crack initiation stage, accounting for 99.2% of the total life. The analysis results show that the fatigue life of the software simulation has the guiding significance for the life evaluation. The fatigue life of the shaft can be quickly calculated by the simulation to reduce the number of fatigue tests and achieve cost-effectiveness.

Gas turbine, the core equipment of the power plant, is capable of rapid starting operation and has less carbon dioxide emission than coal power plant. So it has the advantage of being eco- friendly. In order to increase the efficiency of these gas turbines, the turbine inlet temperature has steadily increased and to ensure the safety of the gas turbine, means for protecting parts exposed to high temperatures have also been developed. Protective coating technology is one of them, which plays the role of lowering the temperature of the base metal and preventing oxidation and corrosion. In this paper, thermal fatigue test simulating the operation environment was conducted using the Amdry 9951 protective coating powder applied to the HPT Heat Shield for the Alstom GT 24 gas turbine and the performance before and after the thermal fatigue test was evaluated and examined by adhesive strength test and SEM (EDS) analysis.

In this paper, fatigue life of extruded aluminium single lap joints, both by self-piercing rivet (SPR) and by hybrid joining (Adhesive-SPR), were characterised based on the quasi-static and fatigue tests. The rivet tail pull-out fracture occurred in the SPR joint specimen under the quasi-static tensile test because the peel stress caused the rivet to separate from the joint. Therefore, adhesive joining was considered to effectively prevent the rivet in the joint specimen from separation. As a result, 68% higher tensile strength of the hybrid joint specimen was observed, compared to that of the SPR joint specimen. From the fatigue tests, the fatigue limit load of SPR joint specimen was found to be 4.8 kN i.e.35% of tensile strength load. The fatigue limit load of the hybrid joint specimen was revealed to be 5.6 kN, i.e., 20% of tensile strength load. Over the fatigue limit load conditions, fracture in base material was shown in the case of SPR joint specimen. Also, fractures in base material and transient failure in adhesives were observed in hybrid joint specimen.