Materialmans use laser technology to prepare micro curved carbon fiber dimension
the surface of the bearing plate on the material through the connecting material of the lead screw nut pair and the upper beam has a great impact on its function. If the properties of the outer surface change, the application range of the material may be expanded. This is why material scientists at Friedrich Schiller University (Germany) studied how to use laser technology to adjust different material tables in experiments. Their main concern is the laser-induced generation of periodic surface structures, also known as lips. LIPSS is an extremely tiny structure. They reported their achievements in this field on carbon, an internationally renowned top journal
Dr. Stephan GR F, Otto Schott Institute for materials research, Jena University, explained: "when a femtosecond laser (a laser with extremely short and strong light pulses) is used to irradiate the surface, a characteristic structure will be formed at the point where the laser beam irradiates the surface, and it is the interference at this focal point that produces LIPSS." Because ordinary laser beams cannot be focused to the required size, these characteristic structures are far smaller than those that can be achieved using normal laser technology. In addition to other parameters, the size of the structure also depends on the laser intensity and excitation environment simulation technology used, which has become an important direction of the development of experimental machine technology. On the basis of careful adjustment of laser beam parameters, the required structure can be almost "customized". At the same time, a large area of periodic patterns can be obtained by scanning the entire surface with a laser beam
current applications in strongly curved surfaces
generally speaking, this method is applicable to a variety of different materials. However, so far it can only be applied to plane. But now Jena materialists have successfully prepared strongly curved surfaces with laser-induced periodic structures. Dr. GR f said, "we have prepared LIPSS with a diameter no larger than the structure itself on the surface of thin carbon fibers of about 10 microns. In addition, we can superimpose different types of structures to form the surface in layers."
at present, these findings will not only cause wear and scratches on the surface of some parts, but also provide new possibilities for practical application. For example, carbon fibers can be embedded into other materials (such as some polymers) to prepare composites, and then chemical treatment can be used to improve the strength of composites. LIPSS can accurately change their surface morphology, so that they can be anchored between the polymer and the embedded fiber
more durable material
in addition, the structure can also be used as an optical diffraction grating. It can change the reflection and absorption behavior of light on the surface in a specific way, which is also applicable to the diffraction behavior of light. And based on the so-called "structure color" concept, the color of the surface can be selectively designed in the future. Therefore, the laser-induced periodic surface structure has attracted more and more attention in the field of optical applications
Dr. GR F, a materials scientist at Jena University, also said: "by changing the surface morphology, the friction coefficient can be reduced, so as to prevent wear. For example, more durable medical implants can be developed in this way." In addition, the wettability of the material can be changed in this way, so it can be designed into a more hydrophobic or hydrophilic material
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