The Influence of Al or B on the Thermoelectric Power of Pt/Pt–Rh Thermocouples
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Horst Brodowsky
,
Martin Ketzner
Abstract
Impurities of Al or B exert a strong influence on the absolute thermoelectric power of Pt and Pt–Rh alloys.
There is a change to less negative values in pure Pt and to more negative values in alloys of more than about 6 wt.% Rh. Consequently, the thermoelectric voltage of thermocouples with one leg of pure Pt is much more sensitive to Al or B impurities than thermocouples made of two different Pt-Rh alloys. The dependence of the absolute thermoelectric power on the valence electron concentration of the alloys studied is correlated to the derivative of the molar susceptibility vs valence electron concentration, as called for by various models connecting thermoelectric phenomena to the band structure of the materials.
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We wish to thank Dr. H. Pausch (Institut für Anorganische Chemie der Universität Kiel) for support with the magnetic measurements. We also wish to thank the Degussa AG for providing Pt and Pt–Rh thermocouples free of charge.
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© 1998 Carl Hanser Verlag, München
Articles in the same Issue
- Frontmatter
- Aufsätze
- The Influence of Al or B on the Thermoelectric Power of Pt/Pt–Rh Thermocouples
- Thermodynamic Modeling of the Co–Dy System
- A Broad Based Analysis of the Thermodynamics of Equation of State of Materials
- Experimental Investigation and Thermodynamic Calculation of the Central Part of the Mg – Al Phase Diagram
- Experimental Liquidus Points and Invariant Reactions in the Cu–Zr System
- Orientation Imaging Microscopy of Alpha Alumina: Sample Preparation and Texture Analysis
- Precipitation and Recrystallization Processes During Ageing of Plastically Deformed Cu-6wt.%Ni-3wt.%Al
- Microstructure, Plastic Deformation Characteristics, and Mechanical Properties of As-cast and Ferritic Heat-treated SG-Iron in a Wide Range of Solidification Cooling Rates
- Microstructure and Mechanical Properties of ( γ + β)-based TiAl Alloys Containing Vanadium and Niobium
- In-situ Formation of TiB2 Reinforced Aluminium via Mechanical Alloying
- The Effect of Combined Forming Methods on the Properties of Al Rods of Circular Cross-section
- Mitteilungen der Deutschen Gesellschaft für Materialkunde e.V.
- Personen
- Buchbesprechungen
- Kalender
Articles in the same Issue
- Frontmatter
- Aufsätze
- The Influence of Al or B on the Thermoelectric Power of Pt/Pt–Rh Thermocouples
- Thermodynamic Modeling of the Co–Dy System
- A Broad Based Analysis of the Thermodynamics of Equation of State of Materials
- Experimental Investigation and Thermodynamic Calculation of the Central Part of the Mg – Al Phase Diagram
- Experimental Liquidus Points and Invariant Reactions in the Cu–Zr System
- Orientation Imaging Microscopy of Alpha Alumina: Sample Preparation and Texture Analysis
- Precipitation and Recrystallization Processes During Ageing of Plastically Deformed Cu-6wt.%Ni-3wt.%Al
- Microstructure, Plastic Deformation Characteristics, and Mechanical Properties of As-cast and Ferritic Heat-treated SG-Iron in a Wide Range of Solidification Cooling Rates
- Microstructure and Mechanical Properties of ( γ + β)-based TiAl Alloys Containing Vanadium and Niobium
- In-situ Formation of TiB2 Reinforced Aluminium via Mechanical Alloying
- The Effect of Combined Forming Methods on the Properties of Al Rods of Circular Cross-section
- Mitteilungen der Deutschen Gesellschaft für Materialkunde e.V.
- Personen
- Buchbesprechungen
- Kalender
