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Nano/micro-imprinting technology base on polymer material coating has attracted the increasing attentions throughout the world in the past several decades, and it is progressively developing into the hot topic at present, in which, how to improve the manufacturing efficiency is becoming the urgent issue to be resolved. Polymer’s curing process is exactly complicated and sophisticated, which involves simultaneously performing physical and chemical changes, when the curing reaction reaches certain level, the system will abruptly transform into insoluble, non-melting gel with rapidly increased viscosity and rigidity, which can generate fixed deformation under persistent external pressure. In this paper, the plastic deformation capacity of epoxy resin in the curing process is investigated by the micro-dimple imprinting experiment, and the relationship between forming precision and curing degree is ascertained adopting the DSC (differential scanning calorimetry) method. In addition, the instantaneous micro-imprinting technology based on the micro-grooves is explored, and the experimental results indicate that the forming precision can surpass 90%. The paper will establish a novel avenue to apply the nano/micro imprinting technology into practical engineering.

The ultimate goal of our research is to develop a wireless, remotely activated, and implantable bone transport (lengthening) device. Our device is subcutaneously mounted on the periosteal surface of the tibia. Smart materials such as temperature-driven nitinol and magnetostrictive terfenol-D were investigated to be used as actuators to provide the required forces for the bone transport process. It was found that an actuator based on terfenol-D with a magnetic field applied transversely (along the material's magnetic moment) was the more appropriate technology. Design concepts and proof-of-concept work of both smart material technologies are presented. [DOI: 10.1115/1.3160314] Keywords: nitinol, terfenol-D, smart magnetostrictive material, smart actuators

Sharkskin effect is progressively coming into the picture in recent several decades, especially focusing on its drag reduction effect in turbulence. The up-to-date research in this article reveals the anisotropic wetting and fluidic phenomena on different sharkskin surfaces. Firstly, the contact angle model based on anisotropic pattern is established. Secondly, the anisotropic wetting and fluidic properties are investigated, and the experimental results can define the relationship between wetting parameters and stretching ratio, and in addition, the anisotropic model is validated. Finally, the possible hypotheses elucidating the wetting model and experiment results are put forward. [ABSTRACT FROM AUTHOR]

Natural selection, survival of the fittest. Through millions of years' evolution, shark has become one of the fastest swimming animals in the ocean, and it is very well-known for sharkskin effect, especially for "sharkskin swimsuit". Due to its great superior properties in drag reduction, anti-wear, self-cleaning and so on, the investigations on the essential mechanisms and fabricating methods have attracted so much attention from all over the world, and the achievements have been widely put into application in industry, agriculture, transportation, airspace and so on, and so lots of profits have been obtained so far. In this paper, the method of fabricating artificial composite drag reduction surface based on biological sharkskin morphology and mucus nano-long chain is investigated and studied, the chemical, mechanical and hydrodynamic properties are explored from different aspects in depth, in which, the experimental results in water tunnel showed that the drag-reducing efficiency could surpass 20% with the smooth skin as reference, and the drag reduction mechanism is systematically explained and discussed from different aspects, which has important significance to understand the recent research status and expand the applications of sharkskin in the fluid engineering. [ABSTRACT FROM AUTHOR]