- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Influence of process parameters on thermal cycle and intermetallic compounds formation in high speed laser weld-brazing of aluminium-steel angle joints
摘要： AA6016-T4 aluminium and DX56D+Z140M steel sheets were joined by fluxless laser weld-brazing process with ER4043 AlSi5 filler wire at high brazing speed. The configuration studied corresponds to typical automotive roof/body-side angle joints. At the interface, the measurements of thermal cycle are performed with K-thermocouples. The results are compared to simulated thermal cycles obtained through SYSWELD Software. Thermal cycles are evaluated with the maximal temperature reached, the time of interaction at high temperature and the cooling speed. Several combinations of laser power and brazing speed are both investigated experimentally and by simulation to study their influence on the thermal cycle and the intermetallic layer thickness. Thermal cycles are discretized to calculate the theoretical growth of the intermetallic compounds with a diffusion-based model. The result is compared to experimental intermetallic layer measured with optical microscopy. The power tends to influence both the maximal temperature and the cooling speed whereas the brazing speed only influences the maximal temperature. The calculation demonstrates the capability to distinguish the process configuration which will lead to the thickest intermetallic layer.
关键词： fluxless laser weld-brazing,simulation,Fe-al dissimilar joints,intermetallic layer calculation,thermal cycle,process parameters
更新于2025-09-12 10:27:22
-
High-throughput screening of laser additive manufactured metallic glass via ultrasonic wave
摘要： Laser additive manufacturing (LAM) technology provides an opportunity to fabricate bulk metallic glasses (BMGs) without any dimensional constraint and achieve the large-scale applications of BMGs. However, flaws, such as cracks, gas porosity, and crystalline phases, are always formed accompanied by the process of LAM, which seriously worsens the mechanical and physical properties of the resulting BMGs. Here, we present a novel method that involves ultrasonic wave technique to high-throughput screen the optimum process parameters for the LAM of BMG. A parameter library, constituted by a series of rectangular BMG samples, is rapidly fabricated by the LAM method under continuously changed combinations of laser power and travel speed. the ultrasonic attenuation factor, which is sensitive to the flaws, is used as the monitor to screen the parameters of the BMGs fabricated by the LAM. Using this approach, the laser power of 1300 W and travel speed of 600 mm/min are estimated as the optimum parameter combination for the LAM of a Zr51ti5ni10cu25Al9 (Zr51) BMG with the slightest flaws. The amorphous-phase dominated microstructure and the sufficiently high tensile strength of the subsequent fabricated large-sized Zr51 BMG sample verify this optimum parameter combination.
关键词： High-throughput screening,Bulk metallic glasses,Ultrasonic wave testing,Optimum process parameters,Laser additive manufacturing
更新于2025-09-11 14:15:04
-
Influence of Substrate Stage Temperature and Rotation Rate on the Magneto-Optical Quality of RF-Sputtered Bi2.1Dy0.9Fe3.9Ga1.1O12 Garnet Thin Films
摘要： Highly bismuth-substituted iron garnet thin films are prepared on quartz substrates by using a radio frequency (RF) magnetron sputtering technique. We study the factors (process parameters associated with the RF magnetron sputter deposition technique) affecting the magneto-optical (MO) properties of ferrite garnet films of composition Bi2.1Dy0.9Fe3.9Ga1.1O12. All ?lms show high MO response across the visible range of wavelengths after being annealed. In particular, the effects of substrate stage temperature and rotation rate on the various properties of ?lms are studied. Experimental results reveal that the characteristics of garnet ?lms of this type can be tuned and optimized for use in various magnetic ?eld-driven nanophotonics and integrated optics devices, and that, at a substrate stage rotation rate near 16 revolutions per minute, the MO quality of the developed MO ?lms is the best, in comparison with ?lms deposited at other rotation rates. To the best of our knowledge, this is the ?rst report on the effects of deposition parameters on the properties of garnet ?lms of this stoichiometry.
关键词： magneto-photonics,Faraday rotation,MO garnets,substrate temperature,process parameters,RF magnetron sputtering
更新于2025-09-10 09:29:36