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Title: A high-stability non-contact dilatometer for low-amplitude temperature-modulated measurements

Abstract

Temperature modulated thermophysical measurements can deliver valuable insights into the phase transformation behavior of many different materials. While especially for non-metallic systems at low temperatures numerous powerful methods exist, no high-temperature device suitable for modulated measurements of bulk metallic alloy samples is available for routine use. In this work a dilatometer for temperature modulated isothermal and non-isothermal measurements in the temperature range from room temperature to 1300 K is presented. The length measuring system is based on a two-beam Michelson laser interferometer with an incremental resolution of 20 pm. The non-contact measurement principle allows for resolving sinusoidal length change signals with amplitudes in the sub-500 nm range and physically decouples the length measuring system from the temperature modulation and heating control. To demonstrate the low-amplitude capabilities, results for the thermal expansion of nickel for two different modulation frequencies are presented. These results prove that the novel method can be used to routinely resolve length-change signals of metallic samples with temperature amplitudes well below 1 K. This high resolution in combination with the non-contact measurement principle significantly extends the application range of modulated dilatometry towards high-stability phase transformation measurements on complex alloys.

Authors:
; ;  [1]
  1. Institute of Materials Physics, Graz University of Technology, A-8010 Graz (Austria)
Publication Date:
OSTI Identifier:
22597810
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 87; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALLOYS; AMPLITUDES; DILATOMETRY; HEATING; INTERFEROMETERS; LASERS; LENGTH; MEASURING METHODS; NICKEL; PHASE TRANSFORMATIONS; SIGNALS; STABILITY; TEMPERATURE MEASUREMENT; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; THERMAL EXPANSION

Citation Formats

Luckabauer, Martin, Sprengel, Wolfgang, and Würschum, Roland. A high-stability non-contact dilatometer for low-amplitude temperature-modulated measurements. United States: N. p., 2016. Web. doi:10.1063/1.4959200.
Luckabauer, Martin, Sprengel, Wolfgang, & Würschum, Roland. A high-stability non-contact dilatometer for low-amplitude temperature-modulated measurements. United States. doi:10.1063/1.4959200.
Luckabauer, Martin, Sprengel, Wolfgang, and Würschum, Roland. 2016. "A high-stability non-contact dilatometer for low-amplitude temperature-modulated measurements". United States. doi:10.1063/1.4959200.
@article{osti_22597810,
title = {A high-stability non-contact dilatometer for low-amplitude temperature-modulated measurements},
author = {Luckabauer, Martin and Sprengel, Wolfgang and Würschum, Roland},
abstractNote = {Temperature modulated thermophysical measurements can deliver valuable insights into the phase transformation behavior of many different materials. While especially for non-metallic systems at low temperatures numerous powerful methods exist, no high-temperature device suitable for modulated measurements of bulk metallic alloy samples is available for routine use. In this work a dilatometer for temperature modulated isothermal and non-isothermal measurements in the temperature range from room temperature to 1300 K is presented. The length measuring system is based on a two-beam Michelson laser interferometer with an incremental resolution of 20 pm. The non-contact measurement principle allows for resolving sinusoidal length change signals with amplitudes in the sub-500 nm range and physically decouples the length measuring system from the temperature modulation and heating control. To demonstrate the low-amplitude capabilities, results for the thermal expansion of nickel for two different modulation frequencies are presented. These results prove that the novel method can be used to routinely resolve length-change signals of metallic samples with temperature amplitudes well below 1 K. This high resolution in combination with the non-contact measurement principle significantly extends the application range of modulated dilatometry towards high-stability phase transformation measurements on complex alloys.},
doi = {10.1063/1.4959200},
journal = {Review of Scientific Instruments},
number = 7,
volume = 87,
place = {United States},
year = 2016,
month = 7
}
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