Reusable spacecraft is increasingly attracting researchers’ attention. However, the experimental investigations on the turbine blade of the rocket engine are rarely published. Thus, the fatigue of a small impulse rocket turbine blade is explored in the current work. First, the specimen and the electrode of electrical discharge machining are carefully designed. Then, the electrical discharge machining is used to machine the specimen. To study the fatigue properties, the finite element analyses are separately performed on the blade model and the specimen. Based on the numerical results, a fatigue test is carried out to reproduce the most vulnerable position. Finally, the microstructural structures of the specimen are detected using the scanning electron microscope (SEM). Results show that (1) different from the aviation field, the specimen is unable to be machined with the welding method because it destroys the crucial details and the mechanical properties; (2) the maximum plastic strain is present at the leading edge close to the hub, at which a 760 μm corner crack appears at the 10113th fatigue cycle. This work provides a feasible method of using the EDM process to machine specimen for the small impulse turbine blade.
When testing impact dynamics of concrete, usually a variety of kinetic effects can be seen, such as the axial and lateral inertial confinement effects, the effects of stress wave propagation and the final friction effects, etc. Some of these are the material is nature itself such as the size effect, some are experimental errors, etc., but all the dynamic effects, may enter the final test results so that unnecessary errors or even wrong values may be brought into experiments. Due to the mechanism of friction effect, we have designed three different sizes of specimen for SHPB test. The quantitative values of the friction effect are obtained. The DIF is corrected, which is the basis for concrete impact engineering design.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.