<?xml version="1.0"?>
<rdf:RDF xmlns:foaf="http://xmlns.com/foaf/0.1/" xmlns:owl="http://www.w3.org/2002/07/owl#" xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dcat="http://www.w3.org/ns/dcat#" xmlns:dct="http://purl.org/dc/terms/" xmlns:adms="http://www.w3.org/ns/adms#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:time="http://www.w3.org/2006/time#" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:vcard="http://www.w3.org/2006/vcard/ns#"><dcat:Dataset rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation"><dct:title>In-situ control of microdischarge characteristics in unipolar pulsed plasma electrolytic oxidation of aluminum</dct:title><dct:description><![CDATA[<p>Microdischarges occurring during plasma electrolytic oxidation are the main mechanism promoting oxide growth compared to classical anodization. When the dissipated energy by microdischarges during the coating process gets too large, high-intensity discharges might occur, which are detrimental to the oxide layer. In bipolar pulsed plasma electrolytic oxidation a so called 'soft-sparking' mode limits microdischarge growth. This method is not available for unipolar pulsing and for all material combinations. In this work, the authors provide a method to control the size- and intensity distributions of microdischarges by utilizing a multivariable closed-loop control. In-situ detection of microdischarge properties by CCD-camera measurements and fast image processing algorithms are deployed. The visible size of microdischarges is controlled by adjusting the duty cycle in a closed-loop feedback scheme, utilizing a PI-controller. Uncontrolled measurements are compared to controlled cases. The microdischarge sizes are controlled to a mean value of A = 5<em>10^-3 mm^2 and A = 7</em>10^-3 mm^2, respectively. Results for controlled cases show, that size and intensity distributions remain constant over the processing time of 35 minutes. Larger, high-intensity discharges can be effectively prevented. Optical emission spectra reveal, that certain spectral lines can be influenced or controlled with this method. Calculated black body radiation fits with very good agreement to measured continuum emission spectra (T = 3200 K). Variance of microdischarge size, emission intensity and continuum radiation between consecutive measurements is reduced to a large extent, promoting uniform microdischarge and oxide layer properties. A reduced variance in surface defects can be seen in SEM measurements, after coating for 35 minutes, for controlled cases. Surface defect study shows increased number density of microdischarge impact regions, while at the same time reducing pancake diameters, implying reduced microdischarge energies compared to uncontrolled cases.</p>
]]></dct:description><dcat:keyword>aluminum</dcat:keyword><dcat:keyword>control</dcat:keyword><dcat:keyword>microdischarge</dcat:keyword><dcat:keyword>oes</dcat:keyword><dcat:keyword>PEO</dcat:keyword><dcat:keyword>plasma</dcat:keyword><dcat:keyword>plasma electrolytic oxidation</dcat:keyword><dcat:theme>Plasma in Liquids, Plasma for Materials / Surfaces</dcat:theme><dct:identifier>5842c0c6-90b7-46e7-883a-c54b2251544f</dct:identifier><dct:issued>2021-01-28T13:35:51+01:00</dct:issued><dct:modified>2021-03-21T19:50:21+01:00</dct:modified><dct:language>en-US</dct:language><dct:publisher>AEPT</dct:publisher><dcat:distribution rdf:resource="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-1"/><dcat:distribution rdf:resource="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-4"/><dcat:distribution rdf:resource="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-5"/><dcat:distribution rdf:resource="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-2"/><dcat:distribution rdf:resource="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-3"/></dcat:Dataset><dcat:Distribution rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-1"><dct:title>Figure 4</dct:title><dct:description><![CDATA[<p>Data corresponding to graphs in figure 4.</p>
<p>Figure 4(a) size evolution:<br />
File: "size.txt"<br />
3 rows delimited by comma:<br />
1. Uncontrolled ,   2. Controlled A = 5<em>10^-3 mm^2,  3. Controlled A = 7</em>10^-3 mm^2<br />
Columns indicate point in time. Distance between data points is t = 1s.</p>
<p>Figure 4(a) number evolution:<br />
File: "Number density.txt"<br />
3 rows delimited by comma:<br />
1. Uncontrolled ,   2. Controlled A = 5<em>10^-3 mm^2,  3. Controlled A = 7</em>10^-3 mm^2<br />
Columns indicate point in time. Distance between data points is t = 1s.</p>
]]></dct:description><dct:issued>2021-02-19T08:08:11+01:00</dct:issued><dct:modified>2021-02-22T10:57:08+01:00</dct:modified><dcat:accessURL rdf:resource=""/><dcat:downloadURL rdf:resource="https://rdpcidat.rub.de/sites/default/files/Size_Number_evolution.zip"/><dcat:mediaType>application/zip</dcat:mediaType><dct:format>data</dct:format><dcat:byteSize>26096</dcat:byteSize><foaf:page>https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-1</foaf:page></dcat:Distribution><dcat:Distribution rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-4"><dct:title>Figure 5</dct:title><dct:description><![CDATA[<p>(a) Data on the controlled and uncontrolled voltage evolution<br />
File:<br />
U_uncontrolled.csv<br />
U_controlled5.csv<br />
U_controlled7.csv</p>
<p>File format:<br />
1. Column: time vector in seconds<br />
2. Column: Measured voltage in Volts</p>
<p>(a) Data on the controlled and uncontrolled duty-cycle evolution<br />
File:<br />
DC_uncontrolled.csv<br />
DC_controlled5.csv<br />
DC_controlled7.csv</p>
<p>File format:<br />
1. Column: time vector in seconds<br />
2. Column: Controlled duty-cycle (between 0...1)</p>
]]></dct:description><dct:issued>2021-02-19T11:51:06+01:00</dct:issued><dct:modified>2021-02-22T10:57:19+01:00</dct:modified><dcat:accessURL rdf:resource=""/><dcat:downloadURL rdf:resource="https://rdpcidat.rub.de/sites/default/files/Voltage_DutyCycle.zip"/><dcat:mediaType>application/zip</dcat:mediaType><dct:format>zip</dct:format><dcat:byteSize>92534</dcat:byteSize><foaf:page>https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-4</foaf:page></dcat:Distribution><dcat:Distribution rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-5"><dct:title>Figure 6</dct:title><dct:description><![CDATA[<p>Current and voltages during one pulse cycle.<br />
Files:<br />
Voltages:<br />
U_uncontrolled.csv<br />
U_controlled5.csv<br />
U_controlled7.csv</p>
<p>Currents:<br />
I_uncontrolled.csv<br />
I_controlled5.csv<br />
I_controlled7.csv</p>
<p>File format:<br />
First column: Time in seconds<br />
Second Column: Uncontrolled Voltage or Current<br />
Third Column: Controlled Voltage or Current  (A = 7<em>10^-3 mm^2)<br />
Fourth Column: Controlled Voltage or Current  (A = 5</em>10^-3 mm^2)</p>
]]></dct:description><dct:issued>2021-02-19T11:56:38+01:00</dct:issued><dct:modified>2021-02-22T10:57:31+01:00</dct:modified><dcat:accessURL rdf:resource=""/><dcat:downloadURL rdf:resource="https://rdpcidat.rub.de/sites/default/files/Voltage_Current.zip"/><dcat:mediaType>application/zip</dcat:mediaType><dct:format>zip</dct:format><dcat:byteSize>13323</dcat:byteSize><foaf:page>https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-5</foaf:page></dcat:Distribution><dcat:Distribution rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-2"><dct:title>Figure 7, 8, 9</dct:title><dct:description><![CDATA[<p>Measured Size and Intensity Distribution for uncontrolled and controlled cases at each point in time (temporal distance between points t = 1s).</p>
<p>Intensity Distribution:<br />
Values between 0-4095.</p>
<p>Corresponding  files for all 3 measurements:<br />
int_dist_uncontrolled.csv<br />
int_dist_controlled_5.csv<br />
int_dist_controlled_7.csv</p>
<p>Each column in a file shows the intensity of every detected microdischarge (comma delimited).<br />
The number of the row corresponds to the time in seconds.</p>
<p>Size Distribution:<br />
Values between 0-4095.</p>
<p>Corresponding  files for all 3 measurements:<br />
size_dist_uncontrolled.csv<br />
size_dist_controlled_5.csv<br />
size_dist_controlled_7.csv</p>
<p>Each column in a file shows the area as the summed number of pixels for every detected microdischarge (comma delimited).<br />
The number of the row corresponds to the time in seconds.</p>
<p>Figure 7:<br />
Scatterplots plotted as intensity and size distribution at a point in time. Data was evaluated at these points in time for uncontrolled and controlled to A_2 = 7*10^-3 mm^2.</p>
<p>Figure 8:<br />
Histograms of photoemission for given time and control regime.<br />
Intensity data evaluated at t = 200s and t = 1400s.</p>
<p>Figure 9:<br />
Histograms of the size distribution for given time and control regime.<br />
Size data evaluated at t = 200s and t = 1400s.</p>
]]></dct:description><dct:issued>2021-02-19T08:19:53+01:00</dct:issued><dct:modified>2021-02-22T10:57:58+01:00</dct:modified><dcat:accessURL rdf:resource=""/><dcat:downloadURL rdf:resource="https://rdpcidat.rub.de/sites/default/files/Distribution.zip"/><dcat:mediaType>application/zip</dcat:mediaType><dct:format>zip</dct:format><dcat:byteSize>5121882</dcat:byteSize><foaf:page>https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-2</foaf:page></dcat:Distribution><dcat:Distribution rdf:about="https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-3"><dct:title>Figure 10, 11, 12 13</dct:title><dct:description><![CDATA[<p>Time evolution of OES Spectra for controlled and uncontrolled cases.</p>
<p>Intensity:<br />
Intensity values of spectra in arbitrary units as a matrix (wavelength x time)<br />
Time separation between spectra is t = 1s.<br />
Files:<br />
OES_controlled.csv<br />
OES_uncontrolled.csv</p>
<p>Wavelength values (in nm):<br />
wavelength.csv</p>
<p>Figure 10:<br />
Waterfall plot of uncontrolled spectra.<br />
Evaluation of OES_uncontrolled.csv</p>
<p>Figure 11:<br />
Waterfall plot of controlled spectra.<br />
Evaluation of OES_controlled.csv</p>
<p>Figure 12:<br />
(a) Evaluation of controlled and uncontrolled emission intensity over time at a wavelength of 802 nm.<br />
(a) Evaluation of uncontrolled spectra at a time of t = 1000s and calculated black body emission.</p>
<p>Figure 13:<br />
(a) Evaluation of controlled and uncontrolled emission intensity over time at a wavelength of 769.9 nm.<br />
(a) Evaluation of controlled and uncontrolled emission intensity over time at a wavelength of 656.3 nm.</p>
]]></dct:description><dct:issued>2021-02-19T08:29:09+01:00</dct:issued><dct:modified>2021-02-22T10:58:09+01:00</dct:modified><dcat:accessURL rdf:resource=""/><dcat:downloadURL rdf:resource="https://rdpcidat.rub.de/sites/default/files/OES_Spectra.zip"/><dcat:mediaType>application/zip</dcat:mediaType><dct:format>zip</dct:format><dcat:byteSize>14508191</dcat:byteSize><foaf:page>https://rdpcidat.rub.de/dataset/situ-control-microdischarge-characteristics-unipolar-pulsed-plasma-electrolytic-oxidation-3</foaf:page></dcat:Distribution><foaf:Agent rdf:about="https://rdpcidat.rub.de/publisher/n0"><foaf:name>DKAN</foaf:name><foaf:homepage>https://rdpcidat.rub.de</foaf:homepage><dct:type rdf:resource="http://purl.org/adms/publishertype/NonProfitOrganisation"/></foaf:Agent></rdf:RDF>
