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High-throughput measurements of thermal conductivity and the coefficient of thermal expansion.

机译：高通量测量导热系数和热膨胀系数。

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摘要

This dissertation presents the development and application of spatially-resolved measurement techniques for high-throughput studies of thermal conductivity and the coefficient of thermal expansion (CTE). Time-domain thermoreflectance (TDTR) has been used for micron-scale thermal conductivity measurements. Time-domain probe beam deflection (TD-PBD), developed in this dissertation, has been used to measure the CTE and, in some cases, Young's modulus with micron-scale spatial resolution. TDTR measurements provide thermal transport property information for the analysis of TD-PBD data.;Localized thermal conductivity measurements of electron-beam physical vapor deposited 8wt% yttria-stabilized zirconia (YSZ) coatings show that the thermal conductivity for heat flow along both the through-thickness and in-plane directions is isotropic and uniform throughout the depth of the YSZ coating. After 500 furnace cycles, the thermal conductivity in the in-plane direction increases from 1.84 +/- 0.08 W m-1 K-1 to 2.2 +/- 0.2 W m-1 K-1.;High-throughput thermal conductivity measurements of binary Ni solid solutions in a diffusion multiple provide large amounts of thermal conductivity data for Ni(Cr), Ni(Pd), Ni(Pt), Ni(Rh) and Ni(Ru) solid solutions. These data are used to test the applicability of the Smith-Palmer equation and the Wiedemann-Franz law for Ni alloys. After subtracting the lattice component calculated by molecular dynamics simulations from the total thermal conductivity, the electronic thermal conductivity of pure Ni is 25% smaller than that predicted from the Wiedemann-Franz law. With the addition of solutes of Pt and Rh, the deviation from the Wiedemann-Franz law decreases. However, the negative deviation of the electronic thermal conductivity of Ni(Pd) alloys from the Wiedemann-Franz law increases slightly to 29% at a Pd concentration of 40 at.%. The Smith-Palmer equation is not a reliable method for predicting the thermal conductivity of Ni solid solution alloys from measurements of the electrical conductivity.;High-throughput CTE measurements are performed on a Fe-Ni diffusion couple to find the Invar composition and test the effect of ion irradiation on CTE. The CTE of Fe-Ni alloys with Ni concentration between 30 at.% and 37 at.% increases upon 2.3-MeV Ar+ irradiation. At the Invar composition Fe65Ni35, the CTE increases from 0.5 x 10-6 K-1 before ion irradiation to 2.4 x 10-6 K -1, 3.0 x 10-6 K-1 and 4.3 x 10 -6 K-1 for ion doses of 0.01, 0.03, and 0.1 displacement per atom, respectively. The increase in CTE is created by the decrease in atomic short-range order upon ion irradiation.;TDTR and TD-PBD are used to study the local properties near the dentin-enamel junction (DEJ) in a human tooth. The thermal conductivity and Young's modulus are uniform in dentin and enamel, respectively, and change abruptly across the dentin-enamel interface. The CTE changes gradually in dentin near the DEJ over a transition width of ≈ 100 mum.
机译：本文介绍了空间分辨测量技术在热导率和热膨胀系数（CTE）高通量研究中的发展和应用。时域热反射率（TDTR）已用于微米级热导率测量。本文开发的时域探测光束挠度（TD-PBD）已用于测量CTE，在某些情况下还可以测量微米级空间分辨率的杨氏模量。 TDTR测量提供了用于分析TD-PBD数据的热传递特性信息。电子束物理气相沉积的8wt％氧化钇稳定的氧化锆（YSZ）涂层的局部热导率测量结果表明，热的热导率沿着两个厚度和面内方向在YSZ涂层的整个深度上都是各向同性的，并且是均匀的。经过500个炉子循环后，面内方向的热导率从1.84 +/- 0.08 W m-1 K-1增加到2.2 +/- 0.2 W m-1 K-1。扩散倍数中的二元Ni固溶体为Ni（Cr），Ni（Pd），Ni（Pt），Ni（Rh）和Ni（Ru）固溶体提供了大量的热导率数据。这些数据用于测试Smith-Palmer方程和Wiedemann-Franz定律对Ni合金的适用性。从总热导率中减去分子动力学模拟计算出的晶格成分后，纯Ni的电子热导率比Wiedemann-Franz定律预测的小25％。随着Pt和Rh溶质的添加，与Wiedemann-Franz定律的偏差减小。但是，Ni（Pd）合金的电子热导率与Wiedemann-Franz定律的负偏差在Pd浓度为40 at。％时会稍微增加到29％。 Smith-Palmer方程不是通过电导率测量来预测Ni固溶合金热导率的可靠方法。;对Fe-Ni扩散偶进行高通量CTE测量以发现因瓦合金成分并测试离子辐照对CTE的影响。在2.3-MeV Ar +辐照下，Ni浓度在30at。％至37at。％之间的Fe-Ni合金的CTE升高。在Invar成分Fe65Ni35上，离子的CTE从离子辐照前的0.5 x 10-6 K-1增加到离子的2.4 x 10-6 K -1、3.0 x 10-6 K-1和4.3 x 10 -6 K-1每个原子的剂量分别为0.01、0.03和0.1个位移。 CTE的增加是由于离子辐照后原子短程顺序的减少而引起的。TDTR和TD-PBD用于研究人牙齿中牙本质-牙釉质接合处（DEJ）附近的局部性质。牙本质和牙釉质的热导率和杨氏模量分别是均匀的，并且在牙本质-牙釉质界面上会突然变化。 CTE在DEJ附近的牙本质中逐渐变化，过渡宽度为＆ap; 100妈

著录项

  • 作者

    Zheng, Xuan.;

  • 作者单位

    University of Illinois at Urbana-Champaign.;

  • 授予单位 University of Illinois at Urbana-Champaign.;
  • 学科 Engineering Mechanical.;Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2008
  • 页码 98 p.
  • 总页数 98
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 机械、仪表工业;工程材料学;
  • 关键词

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