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oe1(光电查) - 科学论文

18 条数据
?? 中文(中国)
  • Parametric study of laser cutting of carbon fibre reinforced polymer (CFRP) and the effect of fibre orientation on cutting quality

    摘要: Laser cutting of CFRP was performed using 2 kW fibre laser. A detailed analysis of the effect of various laser processing parameters on the cutting of CFRP was carried out. The present work considers mainly laser power (W), scan speed (mm/min), gas pressure (bar) and duty cycle (%) as the process parameters with average kerf width and heat affected zone (HAZ) as the output parameters. Cutting of the fibres at 90o with respect to fibre orientation was performed. The SEM and EDS analysis were also performed to understand the cut quality, matrix melting, fibre pullout and vaporisation phenomena of the matrix in the heat affected zone (HAZ). Laser cutting of CFRP with a minimum kerf width of around 184 μm was observed for 800 W, 600 mm/min, 3 bar and 25% duty cycle while HAZ in this parameter was around 1561 μm. Kerf width and HAZ directly increase with an increase in laser power, gas pressure and duty cycle, but they reduce with increase in scan speed. SEM images confirm that the CFRP cutting process generates relatively burr-free fibre edges. Matrix recession and delamination (fibre pullout) were identified as the major quality defects occurring in the laser cutting process of CFRP.

    关键词: fibre delamination,matrix melting,heat affected zone,laser cutting,fibre consolidation,kerf width,CFRP

    更新于2025-11-28 14:24:20

  • Precipitates evolution in the heat affected zone of Mg-Gd-Y-Zr alloy in T6 condition during laser welding

    摘要: The precipitates evolution in the heat affected zone of laser-welded Mg-Gd-Y-Zr alloy in T6 condition was investigated based on the TEM observation. Some oval and long-rod shape precipitates along [2110]α were observed, which were not involved in precipitation sequence. Compared with isothermal aged precipitates, the overaged β′ phase presented same morphology and size, while size of needle-shape β became much smaller. The width of complete dissolution zone of the β′ is smaller than that of partial dissolution and transformation zone.

    关键词: Precipitates evolution,Heat affected zone,Mg-Gd-Y-Zr alloys,Laser welding

    更新于2025-11-28 14:24:20

  • [IEEE 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - Shanghai (2018.8.8-2018.8.11)] 2018 19th International Conference on Electronic Packaging Technology (ICEPT) - A novel organic coating assisted laser drilling method for TSV fabrication

    摘要: Through-silicon vias (TSVs) is a promising three-dimensional packaging solution in post-Moore's law era in the semiconductor industry. The fabrication of through silicon via plays an important role in three-dimensional packaging. Laser drilling is widely used in TSVs fabrication. However, the geometry quality of laser drilling is unsatisfied and heat affected zone (HAZ) is intrinsic. In this work, a novel organic coating assisted picosecond UV laser drilling method is proposed to obtain high-quality TSVs, the HAZ was noticeably eliminated and the TSVs quality was significantly improved. The effects of the organic thickness and laser power on the TSVs' quality were also studied in detail. It is found that the diameter of vias decreases with the increase of the organic thickness and decrease of the laser power. The minimum diameter of TSV obtained by this method is about 15 μm while the aspect ratio is beyond 30. Most importantly, by coating with the organic layer, the minimized via diameter can be decreased to about only 70% of the laser spot size which breaks the limit that the minimized via should be larger than or at least equal to the laser spot size. These findings will be helpful for TSV technology development in modern three-dimensional packaging.

    关键词: ultraviolet picosecond laser drilling,through silicon via,heat affected zone elimination,organics coating method

    更新于2025-09-23 15:22:29

  • Correlation between laser energetic parameters and magnetic properties of GO laminations under surface treatments with long, short or ultra-short pulsed lasers

    摘要: Electromagnetic components mostly incorporate soft magnetic materials used as flux multipliers. Hence, any reduction in iron loss of the magnetic core yields in saving energy. Among the techniques, the local laser treatment is a non-contact method applied for 180° domain refinement (Patri et al. [1]). The present study reassessed the impact of laser treatment on the magnetic properties of grain oriented silicon steels. Various laser pulse widths are used: an ultra-short pulse laser mainly adapted to the ablation process and a long and short pulse durations used for both irradiation and scribing processes [2]. The power loss is measured with a Single Sheet Tester (150 × 150 mm2). Each type of treatment resulted in a power loss reduction of 15–35% at peak induction 1.5 T and frequency 50 Hz. However, only the scribing and the ablation improved also the apparent permeability. In this work, the laser energy parameters are used to estimate the laser impact on the heat affected zone, the groove depth, the induced thermal stress, and on the internal properties of a magnetic behavioral model: static permeability and dynamic magnetization property [3].

    关键词: Groove depth,Heat affected zone,GO laminations,Induced thermal stress,Laser treatment,Magnetic properties

    更新于2025-09-23 15:19:57

  • Microstructure of intercritical heat affected zone and toughness of microalloyed steel laser welds

    摘要: Microstructure of laser welds of the X70 low-carbon pipe steel was studied. High cooling rates after laser welding and non-uniform distribution of carbon in the ferrite-pearlite base metal caused formation of regions with increased microhardness (up to 650 НV) in inter-critical heat affected zone (ICHAZ). These regions consisted of finely dispersed degenerate upper bainite and martensite-austenite constituents of a slender shape and small fraction of a massive shape along the boundaries of bainite laths, as well as twinned martensite. High concentration of martensite-austenite constituents (10–16%) and residual stresses in ICHAZ, as well as a dendritic martensitic structure with carbide interlayers along the boundaries of martensite laths in fusion zone were the main reasons of sharp decrease in charpy impact energy of the welded samples. High microhardness of the laser welds was decreased down to 320 HV and their brittleness was improved by annealing. Also, in ICHAZ, degenerate upper bainite and the regions of martensite-austenite constituents decayed forming tempered sorbite and Fe2C and Fe3C carbides, respectively. Charpy impact energy of the welds doubled after annealing compared to the welds without annealing, and ductile-brittle transition temperature decreased down to –60 °С.

    关键词: Toughness,Heat affected zone,Structure,Laser welding,Low-carbon steel

    更新于2025-09-19 17:13:59

  • [Laser Institute of America ICALEO? 2016: 35th International Congress on Applications of Lasers & Electro-Optics - San Diego, California, USA (October 16–20, 2016)] International Congress on Applications of Lasers & Electro-Optics - Experimental and numerical study on laser welding of glass using a CO2 laser and glass fiber as filler material

    摘要: Automated laser welding with filler wires for bridging gaps and for connecting complex devices has been established for different metal materials. In spite of that, it is still a challenge to transfer this welding process to the brittle material glass. Therefore, glass welding is often realized through a manual process by heating the glass with a gas flame. In addition, welding of non-rotational components requires filler material for gap bridging between the joining partners, which is applied manually today. This work presents an experimental and numerical study on laser welding of fused silica using glass fiber as a filler material to bridge gaps. The goal was to achieve a defined weld penetration depth and heat affected zone which is important for the production of optical elements. Therefore, a CO2 laser heats up the glass components as well as the glass fiber within a temperature controlled welding process. The numerical investigations were used to identify the general process window for welding fused silica. Within the experimental study, the process parameters, such as the defined welding temperature, laser focal spot size, and feed rate were varied to investigate their impact on the welding outcome. In addition, the impact of the filler wire coating on the material composition of the welded component in the joint zone was investigated. Compared to the manual process, laser welding with glass fiber as a filling material leads to a highly reproducible process enabling a high automation level.

    关键词: fused silica,temperature controlled welding,heat affected zone,laser welding,glass fiber,filler material,glass,CO2 laser,weld penetration depth

    更新于2025-09-19 17:13:59

  • Simulation and Experimental Based Analysis of the Laser Beam Welding of DP Steels

    摘要: In this paper, heat affected zone characteristics of DP1000 steels was investigated during diode laser beam welding (LBW). A butt-welded joint of specimen in dimension of 300 x 150 mm each (according to EN15614-11:2002) with 1 mm thickness is used for the experimental purpose. The welding thermal cycle and the cooling circumstances in the HAZ was determined by real experiment and the physical simulation. A Gleeble 3500 thermo-physical simulator was used to physically simulate the coarse grain heat affected zone (CGHAZ) on the base material specimens by the utilization of the thermal cycles for t8/5 =2.5 s. The results of the physical simulation were validated by real welding experiments. The properties of the simulated and the real HAZ was examined by optical microscopic, scanning electron microscope and hardness tests.

    关键词: Gleeble 3500 physical simulator,t8/5 cooling time,Laser beam welding (LBW),dual phase (DP) steel,Heat affected zone (HAZ) characterization

    更新于2025-09-19 17:13:59

  • Dissipative structure of interaction of laser radiation with construction steel 45

    摘要: The article presents the results of a quantitative description of the structure of dissipative structures formed during the interaction of carbon steel 45 with laser radiation, revealing the mechanism of their functioning in a no equilibrium process of interaction of a material with concentrated energy ?ow.

    关键词: Heat-affected zone (HAZ),Molten phase zone (MPZ),Solid-phase hardening zone (SPHZ),Microstructures,Tempering zone (TZ)

    更新于2025-09-16 10:30:52

  • The effect of CO2 laser cutting parameter on Mechanical & Microstructural characteristics of high strength steel-a review

    摘要: Cutting of sheet material is considered as an important process due to its relevance among products of everyday life as well as in high strength application in aircrafts, ships, cars, structures, military, naval purpose etc. Based on recent study it is found that many high strength sheet martial are cut using CO2 laser and it is important to know how the cutting is affecting the material properties and which parameters are responsible for such change. As steel is the most common type of material used in the manufacturing industry so the research is based on the different grade of steels and the effect on those when processed using CO2 laser beam cutting. The various parameters and their effects are shown in the given study which is analyzed by different researchers along the course of time. The material, thickness and different optimization techniques by different researchers is also shown.

    关键词: Microstructural changes,Macro structural changes,Control parameters,Heat Affected Zone,CO2 LBC

    更新于2025-09-16 10:30:52

  • Modeling on surface cut quality of CO2 laser cutting for Austenitic Stainless steel sheet

    摘要: CO2 Laser cutting is the widely used in the cutting process in which quality of ?nished product mainly depends on the input parameters are Laser beam power, Cutting speed and Assist gas pressure. By considering responses are Heat affected zone of the AISI 304 Stainless Steel material. These work we are using response surface methodology are used, in this techniques are very helpful to identi?ed to develop the different mathematical modeling of this processes ?nally best mathematical model are developed.

    关键词: AISI 304,Heat affected zone,CO2 laser cutting,ANOVA,RSM

    更新于2025-09-16 10:30:52