Recently, Zhu Jianqiang, a researcher at the Joint Laboratory of High Power Laser Physics at Shanghai Institute of Optics and Fine Mechanics, and a research team led by Prof. Andy Liu made important research progress in the related technologies of nonlinear optical frequency conversion. A new type of phase matching method-voltage tuning phase matching is proposed and experimentally verified. Related research findings are published in Physical Review Letters, January 27, 2017 [Phys. Rev. Lett. 118,043901, (2017)]. The first author of the paper is PhD student Cui Zijian. Reviewers rated the paper "... the topic of this paper has aroused widespread interest among scientists and has yielded new and reliable results and is expected to open a new perspective in nonlinear optics ...".
The voltage-tuned phase matching method overcomes the problem that the conversion efficiency in the high-power laser system is sensitive to the change of angle, temperature and wavelength by introducing the external electric field and using the linear electro-optic effect of the material to achieve the phase matching so as to obtain the maximum conversion efficiency output. Flexible and precise control of the refractive index of electro-optic materials, and then expand the traditional nonlinear materials, and even low birefringence and isotropic materials in nonlinear optics applications.
To validate this new approach, the research team designed ingenious proof-of-principle experiments. By applying the linear electro-optic effect and the non-linear interaction of light waves simultaneously in a single DKDP crystal, we successfully demonstrated the control of the nonlinear interaction between light waves by using the linear electro-optical effect, and proved the feasibility and effectiveness of this method Sex.
Nonlinear optical frequency conversion techniques have greatly increased the practicality of lasers in various fields and have shown significant scientific potential in many disciplines. In order to obtain efficient frequency conversion, it is an important prerequisite to satisfy the phase matching between the interacting light waves. Due to the dispersion of materials, accurate phase compensation for dispersion caused by dispersion is the main challenge to achieve efficient frequency conversion. Researchers have been trying to solve this problem in different ways. Although 1962 N. Bloembergen et al. Proposed angle tuning and quasi-phase matching. In 1966, Hobden demonstrated the technical solutions such as temperature-tuning phase matching. However, there are still some limitations to the phase matching method. The voltage tuning phase matching method put forward by the research team of Shanghai Institute of Optics and Fine Mechanics not only provides a new way for designing novel nonlinear optics, but also provides a new direction for further research on nonlinear optics interaction. (High Power Laser Physics Joint Laboratory Feed)
(A) the refractive index ellipsoid of the cubic system material; (b) the progress of the nonlinear optical frequency conversion technique of Shanghai Institute of Optics and Technology; (c) the refractive index ellipsoid change of the electro-optic effect of DKDP crystal; and Tune DKDP crystal fourth harmonic generation.
Stamping Parts:
The processing method for stamping and forging are plastic processing (or pressure processing), forging stamping blank collectively. Is hot-rolled and cold-rolled steel sheet and strip. The world of steel, 60 ~ 70% is the plate, mostly made by stamping products. Automobile body, chassis, tank, radiator, boiler drum, vessel shell, electric machine, electric iron core silicon steel sheet are stamping processing. Instruments, household appliances, bicycles, office machinery, household utensils and other products, there are a large number of Stamping Parts stamping. Is powered by conventional or special punching equipment, make sheet metal in the mold directly affected by the deformation force and deformation, thus A certain shape, size and performance of the product parts production technology. The sheet metal, mold and equipment are the three elements of stamping. Temperature divided by stamping hot stamping and cold stamping. The former is suitable for high deformation resistance, sheet metal plasticity is poor; the latter was carried out at room temperature, is commonly used in stamping method the sheet metal plastic processing. It is (or pressure processing) one of the main methods, but also forming part of materials engineering. Stamping mold called stamping die, or die. The die is the material (metal or non-metal) batch processing into the special tool stamping. Die is of vital importance in the in the press, did not meet the requirements of the die, it is difficult to carry out production batch stamping die; no advanced, advanced stamping process can not be achieved. The stamping process and die, stamping equipment and stamping materials to constitute three stamping processing Only when they combine with each other can they get the stamping parts.
WHY Stamping:
Stamping parts and castings, forgings, a thin, uniform, light, strong character. Stamping can be produced from other methods is difficult to manufacture with stiffeners, stamping parts stamping rib, rolling or burring of the workpiece, to improve its rigidity. Because of the use of precision molds, workpiece precision, and high repetition accuracy, specifications, can punch a hole nest, boss. Cold stamping generally no longer cutting machining, or only a small amount of cutting. The hot stamping precision and surface state below the cold stamping, but still better than the casting, forging, machining less.
(1) Stamping processing is of high production efficiency, convenient operation, easy to realize mechanization and automation. This is because the stamping dies and stamping equipment rely on to complete the processing, ordinary press trips per minute up to dozens of times, high pressure per minute up to hundreds or even thousands of times, and each press stroke you may get a red piece.
(2) The stamping die ensure the dimension and shape precision stamping parts, and generally do not damage the surface quality of stamping, and die life is generally longer, so the stamping quality, good interchangeability, "as like as two peas" feature.
(3) Stamping can press the processing size range is large, complex shape parts, such as a small clock stopwatch, large car rails, covering parts, stamping and material hardening effect of cold deformation, punching strength and stiffness are higher..
(4) Stamping generally without cutting scrap generated, material consumption is less, and no other heating equipment, which is a kind of material saving, energy saving and processing, lower the cost of stamping parts.
Category:
Stamping is mainly according to the process of classification, can be divided into separation process and the forming process of two categories. The separation process also known as blanking, its purpose is to make the stamping parts along the contour line must be separated from the sheet, and guarantee the quality of the separation section (Table 1). The forming process is designed to make sheet metal in broken slab under the condition of plastic deformation, the workpiece into the required shape and size. In the actual production, often a variety of integrated process applied to a workpiece. The blanking, bending, shear, tensile, bulging, spinning, correction is the main stamping process of several.
Mainly speaking,based on the three different material,we can make steel stamping farts,copper alloy stamping parts and aluminium alloy stamping parts.
Stamping Parts
Stamping Parts,Steel Stamping,Copper Stamping,Aluminium Stamping
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