Process analysis and hole type optimization of micro-groove multi-pass rolling

Abstract

The micro-grooves with special structure and size have the special function of reducing surface flow resistance. Placing the micro-grooves over a larger area on the aircraft surface can achieve effective drag reduction, that is, a decrease in the resistance experienced during operation. Rolling method can be used to form micro-grooves on metal surface efficiently. However, the micro-grooves formed by this plastic forming method may have some defects, which in turn could cause serious negative impact on the drag reduction and mechanical properties of the micro-grooves. Therefore, optimization of the multi-pass rolling process to avoid the micro-groove defects is of great significance. This paper includes a series of analysis on the microstructure, strain, and material displacement of micro-grooves, which were carried out to explain the causes of micro-groove defects. Micro-grooves were formed on the surface of the sheet, and the plate also underwent both thickness reduction and extension in the Y-direction, under the pressure exerted by the roller. It was found that the extension of the plate had an adverse effect on the formation of micro-grooves; thus, the hole types of the roller were optimized accordingly. The simulation and experimental results showed that the optimized roller could produce the desired micro-grooves, which perfectly eliminated the generation of micro defects.

Investigation of Micropattern Forming Process on Zr‐4 Alloy Surface Considering Plowing Effects

“…Recently, the size effects in the microcoining process on copper surfaces have been quantitatively described by modifying the flow stress, which resulted in the developed model with a prediction error of less than 10% from experiment. [ 4 ] Wang et al [ 5 ] proposed multi‐pass rolling and optimized the hole of the roller for the folding and deflection defects of microgrooves, and finally the optimization was fully verified by experiment and simulation. Ren et al [ 6 ] proposed for the first time an ultrathin metal foil rolling method to manufacturing microcomposite channels, and explored the key parameters of formed microchannels under different rolling processes.…”