Investigation of Micro Holes Fabricated by Femtosecond Laser on S136

2015 ◽  
Vol 727-728 ◽  
pp. 205-208 ◽  
Author(s):  
Lei Zhang ◽  
Xiao Wen Cao ◽  
Deng Peng Huang ◽  
Dong Wei Ran ◽  
Shuo Tian ◽  
...  

Femtosecond laser is now widely used in micro holes drilling because of its unique advantages, such as high efficiency, high precision and non-contact. Femtosecond laser is the best choice to fabricate micro holes. This paper makes a systematic study of the influence of laser power and number of pulses on diameter and depth of micro holes on S136 die steel through the focusing lens with focal length of 35 cm. A series of high-precision micro holes with different diameter and depth are fabricated. The relationship between the dimension of fabricated micro holes and the process parameters is determined.

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Xialun Yun ◽  
Xuesong Mei ◽  
Gedong Jiang ◽  
Zhenbang Hu ◽  
Zunhao Zhang

In order to suppress the spindle vibration with high efficiency and high precision, a no without trial weight spray online balance method is proposed in this paper. By analyzing the relationship between the unbalanced excitation and the unbalanced response of the spindle, the relationship between the dynamic influence coefficient and the system model is studied. A high-speed spindle finite element analysis model was established, and the dynamic influence coefficient matrix was identified. A no trial weight spray online dynamic balancing system was developed, which has the advantages of without trial weight and high-precision loading. A new type of integrated balancing terminal that was formed using 3D printing technology was first proposed by our research group, and its advantages in various aspects are significantly higher than traditional assembly balanced terminals. The experimental verification of the without trial weight spray online dynamic balancing system was performed on a high-speed spindle test stand. Experiments show that the no trial weight spray online balancing method proposed in this paper can achieve high-efficiency and high-precision vibration suppression, greatly reducing balance time and cost of the spindle. At the same time, the online balance test also verified the reliability of the integrated balanced terminal.


2012 ◽  
Vol 523-524 ◽  
pp. 119-124
Author(s):  
Xin Rui Tang ◽  
Keiichi Nakamoto ◽  
Kazushi Obata ◽  
Yoshimi Takeuchi

Recently, in accordance with the technical development and miniaturization of the information equipments, the demand of optic elements with high precision and miniaturization is increased. The mold is used in the manufacture of the optic elements. Thus, it is needed to machine the mold with high efficiency and high precision. As the material of mold, hard material including cemented carbide and ceramics is used. However, it is a problem of the occurrence of severe tool wear when hard material is machined. To solve this problem, the cutting point swivel machining by using the diamond tool with special chamfer was proposed, which has the ability to suppress tool wear and to realize ultraprecise machining. It is confirmed that the cutting point swivel machining has the ability to suppress tool wear by the microgrooving experiment of SiC. This study aims at investigating the effect of the cutting point swivel machining, and making clear the relationship between tool rotation speed and tool wear. As a result, it is known that the actual cutting direction can be changed by using the cutting point swivel machining, and that the chipping of tool becomes conspicuous with increasing tool rotation speed.


2012 ◽  
Vol 268-270 ◽  
pp. 382-386
Author(s):  
Xiao Jun Yang ◽  
Ming Li ◽  
Li Wang ◽  
Hua Long Zhao ◽  
Guang Hua Chen

Based on the femtosecond laser processing technology and PZT driving scanning technology,high-precision micro- manufacturing technology is developed. By adjusting the laser parameters and scanning parameters to get micro-hole machining on the flat or curved surface. Hole’s size and surface morphology is observed by using phase contrast microscopy and scanning electron microscopy observations, and the surface roughness is analyzed by the surface profile instrument. The feasibility of diesel injector nozzle processing is verified in practical industry applications. The results show that this method of making micro hole has significant advantages, such as high precision, good consistency, without burrs, good surface roughness and high efficiency. These characteristics can meet the practical application requirements and can be used in various industrial fields.


Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 236
Author(s):  
Rui Lou ◽  
Guangying Li ◽  
Xu Wang ◽  
Wenfu Zhang ◽  
Yishan Wang ◽  
...  

Antireflection and superhydrophilicity performance are desirable for improving the properties of electronic devices. Here, we experimentally provide a strategy of femtosecond laser preparation to create micro-nanostructures on the graphite surface in an air environment. The modified graphite surface is covered with abundant micro-nano structures, and its average reflectance is measured to be 2.7% in the ultraviolet, visible and near-infrared regions (250 to 2250 nm). The wettability transformation of the surface from hydrophilicity to superhydrophilicity is realized. Besides, graphene oxide (GO) and graphene are proved to be formed on the sample surface. This micro-nanostructuring method, which demonstrates features of high efficiency, high controllability, and hazardous substances zero discharge, exhibits the application for functional surface.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3816
Author(s):  
Xiaojie Li ◽  
Xin Li ◽  
Pei Zuo ◽  
Xiaozhe Chen ◽  
Misheng Liang ◽  
...  

TiO2 is popular in photocatalytic degradation dye pollutants due to its abundance and its stability under photochemical conditions. Au loaded TiO2 can achieve efficient absorption of visible light and deal with the problem of low conversion efficiency for solar energy of TiO2. This work presents a new strategy to prepare Au nanoparticles-loaded TiO2 composites through electric−field−assisted temporally−shaped femtosecond laser liquid-phase ablation of Au3+ and amorphous TiO2. By adjusting the laser pulse delay and electric field parameters, gold nanoparticles with different structures can be obtained, such as nanospheres, nanoclusters, and nanostars (AuNSs). AuNSs can promote the local crystallization of amorphous TiO2 in the preparation process and higher free electron density can also be excited to work together with the mixed crystalline phase, hindering the recombination between carriers and holes to achieve efficient photocatalytic degradation. The methylene blue can be effectively degraded by 86% within 30 min, and much higher than the 10% of Au nanoparticles loaded amorphous TiO2. Moreover, the present study reveals the crystallization process and control methods for preparing nanoparticles by laser liquid ablation, providing a green and effective new method for the preparation of high-efficiency photocatalytic materials.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1200
Author(s):  
Yong-Joon Jun ◽  
Seung-ho Ahn ◽  
Kyung-Soon Park

The Green Remodeling Project under South Korea’s Green New Deal policy is a government-led project intended to strengthen the performance sector directly correlated with energy performance among various elements of improvement applicable to building remodeling by replacing insulation materials, introducing new and renewable energy, introducing high-efficiency equipment, etc., with public buildings taking the lead in green remodeling in order to induce energy efficiency enhancement in private buildings. However, there is an ongoing policy that involves the application of a fragmentary value judgment criterion, i.e., whether to apply technical elements confined to the enhancement of the energy performance of target buildings and the prediction of improvement effects according thereto, thus resulting in the phenomenon of another important value criterion for green remodeling, i.e., the enhancement of the occupant (user) comfort performance of target buildings as one of its purposes, being neglected instead. In order to accurately grasp the current status of these problems and to promote ‘expansion of the value judgment criteria for green remodeling’ as an alternative, this study collected energy usage data of buildings actually used by public institutions and then conducted a total analysis. After that, the characteristics of energy usage were analyzed for each of the groups of buildings classified by year of completion, thereby carrying out an analysis of the correlation between the non-architectural elements affecting the actual energy usage and the actual energy usage data. The correlation between the improvement performance of each technical element and the actual improvement effect was also analyzed, thereby ascertaining the relationship between the direction of major policy strategies and the actual energy usage. As a result of the relationship analysis, it was confirmed that the actual energy usage is more affected by the operating conditions of the relevant building than the application of individual strategic elements such as the performance of the envelope insulation and the performance of the high-efficiency system. In addition, it was also confirmed that the usage of public buildings does not increase in proportion to their aging. The primary goal of reducing energy usage in target buildings can be achieved if public sector (government)-led green remodeling is pushed ahead with in accordance with biased value judgment criteria, just as in the case of a campaign to refrain from operating cooling facilities in aging public buildings. However, it was possible to grasp through the progress of this study that the remodeling may also result in the deterioration of environmental comfort and stability, such as the numerical value of the indoor thermal environment. The results of this study have the significance of providing basic data for pushing ahead with a green remodeling policy in which the value judgment criteria for aging existing public buildings are more expanded, and it is necessary to continue research in such a direction that the quantitative purpose of green remodeling, which is to reduce energy usage in aging public buildings, and its qualitative purpose, which is to enhance their environmental performance for occupants’ comfort, can be mutually balanced and secured at the same time.


Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 398
Author(s):  
Yaroslav S. Derbenev ◽  
Yury N. Filatov ◽  
Anatoliy M. Kondratenko ◽  
Mikhail A. Kondratenko ◽  
Vasiliy S. Morozov

We present a review of the possibilities to conduct experiments of high efficiency in the nuclear and high energy physics with spin-polarized beams in a collider complex, configuration of which includes Siberian snakes or figure-8 collider ring. Special attention is given to the recently elicited advantageous possibility to conduct high precision experiments in a regime of the spin transparency (ST) when the design global spin tune is close to zero. In this regime, the polarization control is realized by use of spin navigators (SN), which are compact special insertions of magnets dedicated to a high flexibility spin manipulation including frequent spin flips.


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