Huazhong University of Science and Technology

Wuhan Nrd Laser Engineering Co., Ltd.

Wuhan Hivalue Intelaser Ltd.

Xiaoyan Zeng

Chongyang Li

Yongfeng Lu

Qianwu Hu

Zhongqi Hao

Jiaming Li

Xiangyou Li

Ming Jiang

Lianbo Guo

Yinlan Zheng

Xinyan Yang

Dengzhi Wang

Zhao Ren

Rongxing Yi

Li Meng

Min Du

Kaiwen Wei

Kun Li

Pinghua Guo

Mengna Liu

Ran Zhou

Youguang Fan

Yun Tang

Xiaoming Xu

Meng Shen

Ping Yang

A laser powder bed fusion forming device for a large-size ring/frame-shaped metal piece. Said device includes a forming cylinder, a substrate, a galvanometer array and a dust removal module. The forming cylinder is ring/frame-shaped and is adapted to the inner and outer contours of the ring/frame-shaped metal piece to be formed. The substrate is also ring/frame-shaped and is arranged inside the forming cylinder. The galvanometer array is located above the forming cylinder, includes a plurality of galvanometer systems, and the corresponding scanning areas thereof cover the upper surface of the forming cylinder. The dust removal module is located between the forming cylinder and the galvanometer array, and is used for forming a circulating air flow field which is distributed along the radial direction of the ring-shaped metal piece or along the circumscribed circle of the horizontal cross-section of the frame-shaped metal piece or along some other specific directions.

Laser powder bed fusion forming device and method for large-size ring/frame-shaped metal piece

An onsite steel rail laser processing engineering vehicle, including a laser processing power engineering vehicle and a laser processing cart, the laser processing power engineering vehicle is connected to the laser processing cart; the onsite steel rail laser processing engineering vehicle further comprises a transport mechanism disposed on the laser processing power engineering vehicle; through movement and rotation, the transport mechanism transports the laser processing cart into the laser processing power engineering vehicle or transports the laser processing cart out from the laser processing power engineering vehicle and places it on rails.

Onsite steel rail laser processing engineering vehicle

The present invention belongs to the technical field of elemental analysis, and more particularly, relates to a dynamic calibration method for echelle spectrometer in laser-induced breakdown spectroscopy, comprising: S1: collecting a standard light source by using an echelle spectrometer; S2: in combination with a calibration function, calculating a pixel position coordinate ({circumflex over (x)},&#x177;) corresponding to a spectral wavelength &#x175;; S3: performing dynamic searching and filtering near the pixel position coordinate ({circumflex over (x)},&#x177;) to obtain a set D of all pixel position coordinates, and adjusting all original intensity values in the set D to obtain intensity values F(I), and S4: calculating a spectral line intensity value after dynamic calibration by summing the adjusted intensity values F(I), thereby completing dynamic calibration of the result of the echelle spectrometer. The method in the present invention can overcome the shortcoming, i.e., the existing echelle spectrometer is only calibrated before measurement without solving the spectral line drift during use, increasing the absolute intensity of the wavelength and reducing the detection limit of the quantitative analysis, as well as improving the precision of the quantitative analysis of an element to be analyzed.

Dynamic calibration method for echelle spectrometer in laser-induced breakdown spectroscopy

The present invention belongs to the field of laser plasma emission spectrometry, and in particular relates to a method for improving the detection sensitivity on a carbon element in laser-induced breakdown spectroscopy. The method specifically comprises the following steps: ablating the surface of a sample to be tested by using a laser beam emitted so as to rapidly heat the surface of the sample and the ambient air close to the surface of the sample into plasma, atomize carbon in the sample and nitrogen in the ambient gas, and combine carbon with the nitrogen into C&#x2014;N radicals; tuning a wavelength-tunable laser to a wavelength needed by stimulated absorption transition of C&#x2014;N radicals, and outputting a laser beam to radiate the plasma so that stimulated absorption transition of C&#x2014;N radicals is carried out, then fluorescent signals are emitted with spontaneous radiative transition; collecting and recording an emission fluorescence spectrum of the C&#x2014;N radicals; and qualitatively or quantitatively analyzing on carbon element. By adopting the method provided by the invention, in a case of hardly affecting the matrix spectrum, C&#x2014;N radical signal can be enhanced in high selectivity, thereby avoiding the interference generated by the matrix, and spectrum signals of the carbon element in the plasma can be enhanced, thereby improving the detective sensitivity of LIBS on carbon element.

Method for improving detective sensitivity on carbon element in laser-induced breakdown spectroscopy

Provided are a method and an apparatus for laser quenching. The method utilizes a scanning galvanometer, and involves laser quenching via irradiation with intermittent, repeated scans, rather than a single scan as in the prior art. The method results in increased laser energy absorbed by the metal base and improved depth of thermal conduction, while avoiding melting at the metal surface, thus providing a significantly improved laser quenching process. The apparatus can include a laser, a control system, a light guiding system, a mechanical motion device and a galvanometer.

Method and apparatus for laser quenching

Provided is a method for inhibiting self-absorption effect of a LIBS, comprising ablating a to-be-measured sample via a pulse laser thereby generating plasma, and selectively stimulating the plasma using a wavelength-tunable laser beam enabling transition of particles in a ground-state in the plasma to high energy state as stimulated absorption, thereby improving a stimulated absorption transition efficiency of the particles in a ground-state, and preventing plasma spectrum from being influenced by self-absorption effect. The invention is capable of eliminating the self-absorption effect without introducing external interference, obtaining original characteristics of emission spectrum from the center of the plasma, and essentially inhibiting and finally eliminating the self-absorption effect of laser plasma by making use of intrinsic physical property of plasma.

Method for inhibiting self-absorption effect in laser-induced breakdown spectroscopy

The invention discloses an on-line laser processing vehicle for a rail, including a chassis, a vehicle body, a steer-control chamber and a container; the steer-control chamber includes a console, a CCD monitoring system and a drive-switching operating system; a dual driving system and switching mechanism, which with a process-operation driving system, a conventional operation driving system and a switching mechanism, is disposed in the container; the process-operation driving system operates to provide driving power for the laser processing vehicle during laser processing, and precisely controls moving speed and distance of the laser processing vehicle; the switching mechanism operates to implement switching between the conventional operation driving system and the process-operation driving system. The invention ensures accurate processing trajectories of the laser processing vehicle during laser processing; facilitates on-line laser processing of a variety of rails, such as the rails of main line, curved rails, guard rails, switch rails and so on, so that wear resistance of the processed rail is greatly improved, and meets requirements of high-speed and heavy haul trains for wear resistance of the rail.

Onsite steel rail laser processing vehicle

Growing community of inventors

Hubei, China

Xiaoyan Zeng