A Controlled Material Flow Forming Mechanism of Curve Cutter Forging in The Hot Impression Forging of The Medical Instrument

In this study, a forming process during producing medical surgery curve cutter stapler would be tentatively as well as numerically investigated and validated by the simulations. The reasons for the investigation are to find the critical technology of the forming process and to understand this medical tool head forming within the forming process associated with medical surgery curve cutter stapler and improve the traditionally forming process. Moreover, to understand the medical tool head forming, the novel forging process, and the parting line approach are offered and simulated by the FE software QForm, the method data on the medical tool head forging are investigated and compared with the experimental analysis. According to the outcomes of the simulations, the distributions of the forming process, some parameters have been gotten to explain and improve these microscopic phenomena. The precision of the numerical patterns has been confirmed by comparing them with the test dimensions. The offered revised model from the forming preform has been submitted to achieve an alike forging condition when reducing manufacturing cost After the improved method, measure the shrinkage width of the workpiece. Compared with the product of the traditional process, the widest area is 6.37mm shrink to 6.29mm. The shrinkage is about 1%. Compared with the previous result is 5%, the improvement plan has been optimized the outcomes very much.

Aerodynamics-assisted, efficient and scalable kirigami fog collectors

To address the global water shortage crisis, one of the promising solutions is to collect freshwater from the environmental resources such as fog. However, the efficiency of conventional fog collectors remains low due to the viscous drag of fog-laden wind deflected around the collecting surface. Here, we show that the three-dimensional and centimetric kirigami structures can control the wind flow, forming quasi-stable counter-rotating vortices. The vortices regulate the trajectories of incoming fog clusters and eject extensive droplets to the substrate. As the characteristic structural length is increased to the size of vortices, we greatly reduce the dependence of fog collection on the structural delicacy. Together with gravity-directed gathering by the folds, the kirigami fog collector yields a collection efficiency of 16.1% at a low wind speed of 0.8 m/s and is robust against surface characteristics. The collection efficiency is maintained even on a 1 m2 collector in an outdoor setting.

DEVELOPMENT OF A FICH PROTECTION DEVICE DESIGN

The water intake structure is a functional element of the water supply system, but it must also be a fish protection object. The following basic requirements are imposed on the devices of modern fish protection devices at water intakes: prevention of ingress and death of young fish and larvae, prevention of injury to young fish and larvae, removal of protected fish from water intake, reliability of operation under specific conditions and means. According to the principle of operation, the most effective is the active scheme, with the forced formation of the hydraulic flow structure. The design of a universal combined type device with the use of a jet generator as a flow-forming element that creates a reactive hydraulic movement designed to protect fish and juveniles with a body size of less than 15 mm is proposed.

Mechanical Properties and Microstructure of A356-T6 Aluminum Alloy Wheel Hub Based on Casting-Spinning Process

The mechanical properties and microstructure of the A356-T6 wheel hub based on low pressure die casting-hot flow forming process were analyzed by means of optical microscopy (OM), scanning electron microscopy (SEM) and tensile tests. Results showed that the size of the eutectic region and the morphology of the Si phase were the main factors affecting the mechanical properties and fracture morphology of the wheel hub. There was a uniform distribution of eutectic area and fine Si phase morphology in the microstructure of the upper rim and lower rim, moreover, the ultimate tensile strength and yield strength of the upper rim reached 282.4MPa and 185.1MPa, respectively. The fractures were mainly composed of fine quasi-cleavage platform and dimple. The microstructure of the rim showed a long strip along the deformation direction and the eutectic structure and Si particles were uniformly distributed. Irregular polygonal eutectic regions and coarse rod-like Si particles were accumulating in the spoke, causing a serious decrease in mechanical properties, especially in the spoke center and spoke R angle.