ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The proper control of total impurities and oxygen contents of oxygen-free highconductivity (OFHC) copper prepared by vacuum high-frequency melting technique was studiedusing Mahalanobis-Distance (MD) outlier detection method as functions of raw material purities,vacuum pressure, melting temperature and holding time. The properties of vacuum-melted OFHCcopper was examined by thermo-gravimetric analysis, differential scanning calorimetry, hardnesstest, macro and optical microstructure analyses and ultimate tensile test. In multivariate systems, theexistence of outlier makes it difficult to analyze the system and oultier detection belongs to the mostimportant tasks in experimental data analysis. Mahalanobis Distance is most commonly used as adiagnosis of existance of outlier in multivariate system. The relationship between experimentconditions and total impurities and oxygen contents can be defined with the regression analysisresults. At this research, our desirable manufacturing conditions is to obtain the total impuritiesunder 40 ppm and oxygen contents under 5 ppm. After this statistical approach, the suggestedminimum maufacturing conditions are the purity of raw material was 4N, vacuum pressure was 10-1torr, melting temperature was 1150℃ and melt holding time was 20 minutes
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/16/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.544-545.965.pdf
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