کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
792980 1466747 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Spectroscopic monitoring of metallic bonding in laser metal deposition
ترجمه فارسی عنوان
نظارت تلسکوپیک بر پیوند فلزی در رسوب لیزر فلز
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی صنعتی و تولید
چکیده انگلیسی


• A spectrometer is used for process monitoring during laser metal deposition (LMD).
• Spectral analysis on optical emissions during LMD is linked to clad layer quality.
• The onset of metallic bonding is detected from Fe I absorption lines.
• Dilution is related to an electron temperature analysis of four Cr I lines.
• Combination of both signals can be used to build a robust control system for LMD.

A new approach is presented in this paper to link optical emission spectrum analysis to the quality of clad layers produced with laser metal deposition (LMD). A Nd:YAG laser (λ = 1.064 μm) was used to produce clad tracks with Metco 42C powder on AISI 4140 steel substrate. The laser power was ramped in steps of 220 W from 800 W to 2780 W focusing the laser beam into a 4.8 mm diameter spot. A constant cladding speed of 10 mm s−1 is used with a powder feeding rate of 0.36 g s−1. The extent of metallic bonding is evaluated from dilution data obtained by measuring the melt depth in the substrate from cross sections of the clads. The spectra generated during the deposition process were collected with an optical spectrometer attached to the laser head. The discrete spectral lines from the collected spectra were identified from the NIST database as Fe I and Cr I lines. Two different spectral analysis methods were used, namely the calculation of the electron temperature Te and the intensity ratio IR. The electron temperature Te is computed from four discrete Cr I lines at 526.415, 529.827, 532.834, and 534.044 nm wavelength. The intensity ratio IR is a measure of the absorption of a discrete Fe I line at 588.91 nm. The analysis of the collected spectra indicates that onset and extent of metallic bonding can be detected with a spectrometer during the deposition process. A sudden decrease of the IR signal during the LMD process indicates the onset of metallic bonding. A further increase of the laser power mainly contributes to an increase in melt depth, leading to a higher dilution. In this region, the Te signal shows a better correlation with the dilution.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Materials Processing Technology - Volume 220, June 2015, Pages 276–284
نویسندگان
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