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CN109613054A - A method for measuring the longitudinal thermal conductivity of direct energization - Google Patents

A method for measuring the longitudinal thermal conductivity of direct energization Download PDF

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CN109613054A
CN109613054A CN201811533289.8A CN201811533289A CN109613054A CN 109613054 A CN109613054 A CN 109613054A CN 201811533289 A CN201811533289 A CN 201811533289A CN 109613054 A CN109613054 A CN 109613054A
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thermal conductivity
resistance
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CN109613054B (en
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杨决宽
孔龙
陈云飞
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Southeast University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N25/00—Investigating or analyzing materials by the use of thermal means
    • G01N25/20—Investigating or analyzing materials by the use of thermal means by investigating the development of heat, i.e. calorimetry, e.g. by measuring specific heat, by measuring thermal conductivity

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Abstract

本发明公开了一种直接通电纵向导热系数测试方法，将被测样品置于真空恒温腔内，并以四电极方式连接在测量电路中，控制真空恒温腔温度稳定在给定值，对被测样品段同时施加直流和交流电流，得出被测样品段在给定温度下的电阻R0和斜率b；改变真空腔的温度得到不同温度下的电阻R0和斜率b，从而获得被测样品段的电阻温度系数α和各温度下的导热系数λ‑侧面换热系数h曲线；在每个测量温度下，不同被测样品段的两次测试给出了两条不平行的λ‑h曲线，求这两条λ‑h曲线的交点(hc，λc)，得到该温度下被测样品真实的侧面换热系数hc和导热系数λc。本发明消除了侧面换热对于纵向导热系数测试的影响，可用于线材、微米纤维、以及一维纳米结构纵向导热系数测试。

The invention discloses a method for measuring the longitudinal thermal conductivity of direct energization. A sample to be tested is placed in a vacuum constant temperature chamber and connected to a measuring circuit in a four-electrode manner, and the temperature of the vacuum constant temperature chamber is controlled to be stable at a given value. Apply DC and AC current to the sample section at the same time to obtain the resistance R 0 and slope b of the sample section under test at a given temperature; change the temperature of the vacuum chamber to obtain the resistance R 0 and slope b at different temperatures, so as to obtain the measured sample The temperature coefficient of resistance α of the section and the thermal conductivity λ-lateral heat transfer coefficient h curve at each temperature; at each measurement temperature, two tests of different tested sample sections gave two non-parallel λ-h curves , find the intersection point (h c , λ c ) of these two λ‑h curves, and obtain the real side heat transfer coefficient h c and thermal conductivity λ c of the tested sample at this temperature. The invention eliminates the influence of side heat exchange on the longitudinal thermal conductivity test, and can be used for the longitudinal thermal conductivity test of wires, micron fibers and one-dimensional nanostructures.

Description

A kind of direct-electrifying longitudinal direction Determination of conductive coefficients method
Technical field
The invention belongs to thermal physical property of solid material parameter testing technical fields, and in particular to a kind of direct-electrifying is longitudinally thermally conductive Coefficient testing method.
Background technique
Direct-electrifying method is one of main test method of conductive material thermal coefficient.It leads the longitudinal direction that can be used to measure wire rod Hot coefficient can also be used to the thermally conductive system in longitudinal direction for measuring single micrometer fibers, one-dimensional nano structure such as GB/T 3651-2008 Number.During the test, electric current is applied to sample, generates Joule heat to heat sample.Part Joule heat is along sample Longitudinal direction reaches substrate, and another part Joule heat is lost by the heat convection and radiation heat transfer of sample side.Accurately It determines the sample side coefficient of heat transfer, determines the measuring accuracy of direct-electrifying method longitudinal direction thermal coefficient.
For characteristic size in the sample of millimeter magnitude, GB/T 3651-2008 when not being powered, uses thermoelectricity first The temperature difference between the temperature difference and environment and sample of even measurement sample itself, so as to find out sample side and The coefficient of heat transfer of environment.Then in energization, the temperature of sample and environment is measured, the axial direction for finding out sample is led Hot coefficient.Method in GB/T 3651-2008 has modified the influence that side exchanges heat for measurement result.But it exchanges heat in side and is When number is larger, the method in GB/T 3651-2008 cannot obtain satisfied as a result, especially to the lower material of thermal conductivity, problem More prominent (Hu Peng, publishing house, Chen Zeshao Measure Technology of Heat & Thermophysics (second edition) China Science & Technology University, 2009, 120-122)。
Particularly, it when measuring micrometer fibers or one-dimensional nano structure, is surveyed since external temperature sensor can not be used The temperature of sample is measured, therefore the testing process in GB/T 3651-2008 is no longer applicable in.Due to accurately measuring single micron The side coefficient of heat transfer of fiber or one-dimensional nano structure is extremely difficult, therefore micrometer fibers or one-dimensional nano structure thermal coefficient are surveyed In examination, usually ignore the influence of side heat exchange, or estimate the side coefficient of heat transfer using posture material radiant emissivity, causes There are large errors for test result.
Summary of the invention
Goal of the invention: the invention proposes a kind of direct-electrifying longitudinal direction Determination of conductive coefficients methods, can simultaneously obtain tested The longitudinal thermal coefficient and the side coefficient of heat transfer of sample, to eliminate the influence that side exchanges heat for longitudinal Determination of conductive coefficients.
A kind of technical solution: direct-electrifying longitudinal direction Determination of conductive coefficients method of the present invention, comprising the following steps:
(1) that sample is placed in vacuum constant temperature is intracavitary, and is connected in measuring circuit with four electrode approach, wherein internal Sample segments between two electrodes are sample section；
(2) control vacuum constant temperature chamber temperature is stablized in given value, sample section is applied simultaneously DC current with exchange Electric current obtains the resistance R of sample section at such a temperature0With slope b；
(3) temperature for successively changing vacuum chamber repeats step (2), obtains the resistance R under different temperatures0With slope b, obtain The temperature-coefficient of electrical resistance α of sample section and thermal coefficient λ-side coefficient of heat transfer h curve at each temperature；
(4) the distance between (1) described internal electrode is changed the step, step (2)-(3) are repeated；
(5) at a temperature of each measurement, it is bent that the test twice of different sample sections gives two not parallel λ-h Line finds out the intersection point (h of this two λ-h curvesc, λc), hcThe as true side coefficient of heat transfer of sample at this temperature, λc As longitudinal thermal coefficient of sample at this temperature.
The sample segment length is 20 times or more of sample diameter or thickness.
The sample is connected in measuring circuit with four electrode approach, wherein two electrodes of outside are current feed, Internal two electrodes are used for voltage lead.
The step (2) the following steps are included:
(21) DC current is used to detect the resistance of sample section for heating sample section, alternating current；
(22) AC voltage drop in sample section is measured, the resistance R of sample segments is calculated；It measures on sample Direct current pressure drop calculates the Joule heat UI generated in sample section, and carries out linear fit to R and UI:
R=R0+b×UI (1)
Obtain the resistance R of sample section at a given temperature0With slope b.
The step (3) the following steps are included:
(31) using the R under different temperatures0Calculate the temperature-coefficient of electrical resistance α of sample section:
(32) at a temperature of each measurement, it is assumed that a side coefficient of heat transfer h obtains one by following formula and corresponding leads Hot coefficient lambdah:
Wherein, AsFor the lateralarea of sample section, L is sample segment length, and P is sample section cross section Perimeter, AcFor the cross-sectional area of sample section.
The utility model has the advantages that compared with prior art, the invention has the benefit that by carrying out different length twice to sample Measurement, while obtaining longitudinal thermal coefficient of the sample side coefficient of heat transfer and sample, side heat exchange can be eliminated and led for longitudinal The influence of hot coefficient test, and operating procedure is simple, measurement result is accurate.
Detailed description of the invention
Fig. 1 is test method schematic diagram of the present invention；
Fig. 2 is λ-h curve graph under different temperatures.
Specific embodiment
The present invention is described in further details with embodiment with reference to the accompanying drawing.
By taking the carbon fiber test that diameter is 8 μm as an example, direct-electrifying longitudinal direction Determination of conductive coefficients method of the invention, including Following steps:
(1) referring to Fig. 1, sample 1 is placed on four intracavitary electrodes 2 of vacuum constant temperature, to realize sample 1 with four electricity Pole mode is connected in measuring circuit.Electrode 2 is fixed in substrate 3.Sample segments between internal two electrodes are sample section, In the present embodiment, sample segment length is 7.25mm.
(2) control constant temperature chamber temperature stablize 300K, using current source 4 in sample 1 simultaneously apply direct current with exchange Electric current, wherein DC current is used to detect the resistance of sample section for heating sample section, alternating current.
Measure the AC voltage drop v in sample sectionac, calculate the resistance R=v of sample segmentsac/iac, measure detected sample Direct current pressure drop U in product section, calculates the Joule heat UI generated in sample section.Linear fit is carried out to R and UI:
R=R0+b×UI (1)
Obtain the resistance R of sample section at a given temperature0With slope b.
(3) temperature for successively changing vacuum chamber is 290-250K, and repeats step (2) at each temperature, obtains difference At a temperature of R0And b.
According to the definition of temperature-coefficient of electrical resistance
Use the R under different temperatures0Calculate the temperature-coefficient of electrical resistance α of sample section.
Basic theories according to steady state heat transfer is available, in above-mentioned heating process, the average temperature rising of sample section For
A in formulasFor the lateralarea of sample section, h is the side coefficient of heat transfer, and h is sample segment length, and P is quilt The perimeter of sample section cross section, AcFor the cross-sectional area of sample section, λ is the thermal coefficient of sample.According to electricity Temperature coefficient definition is hindered, is in average temperature risingWhen, the resistance of sample can be expressed as
It is available by formula (1), (3), (5)
At a temperature of each measurement, by assuming that a series of possible side coefficient of heat transfer h, obtain a system by formula (6) Arrange corresponding thermal coefficient λ.In this way at a temperature of each measurement, a λ-h curve is obtained, as shown in Figure 2.
(4) change the distance between electrode 2, to change the length of sample section, in this embodiment, sample segments Length becomes 5.62mm, repeats step (2)-(3).
(5) at a temperature of each measurement, above-mentioned test twice gives two not parallel λ-h curves.What Fig. 2 was provided is Two λ-h curves when 300K.Seek the intersection point (h of this two λ-h curvesc, λc), hcThe as true side of sample at this temperature The coefficient of heat transfer, λcThe as true longitudinal thermal coefficient of sample 1 at this temperature.In the present embodiment, it is found out by Fig. 2 Coefficient of heat transfer h in side when 300Kc=3.04W/m2- K, sample longitudinal direction thermal coefficient λc=9.34W/m-K.

Claims (5)

1.一种直接通电纵向导热系数测试方法，其特征在于，包括以下步骤：1. a direct energization longitudinal thermal conductivity test method, is characterized in that, comprises the following steps: (1)将被测样品置于真空恒温腔内，并以四电极方式连接在测量电路中，其中内部两电极之间的样品段为被测样品段；(1) Place the sample to be tested in a vacuum constant temperature chamber, and connect it to the measurement circuit in a four-electrode manner, wherein the sample segment between the two internal electrodes is the sample segment to be tested; (2)控制真空恒温腔温度稳定在给定值，对被测样品段同时施加直流电流和交流电流，得出被测样品段在该温度下的电阻R0和斜率b；(2) Control the temperature of the vacuum constant temperature chamber to be stable at a given value, and apply DC current and AC current to the tested sample section at the same time to obtain the resistance R 0 and slope b of the tested sample section at this temperature; (3)依次改变真空腔的温度重复步骤(2)，得到不同温度下的电阻R0和斜率b，获得被测样品段的电阻温度系数α和各温度下的导热系数λ-侧面换热系数h曲线；(3) Repeat step (2) by sequentially changing the temperature of the vacuum chamber to obtain the resistance R 0 and slope b at different temperatures, and obtain the resistance temperature coefficient α of the tested sample section and the thermal conductivity λ at each temperature - side heat transfer coefficient h curve; (4)改变步骤(1)所述内部电极之间的距离，重复步骤(2)-(3)；(4) changing the distance between the internal electrodes described in step (1), repeating steps (2)-(3); (5)在每个测量温度下，不同被测样品段的两次测试给出了两条不平行的λ-h曲线，求出这两条λ-h曲线的交点(hc，λc)，hc即为该温度下被测样品真实的侧面换热系数，λc即为该温度下被测样品的纵向导热系数。(5) At each measurement temperature, two non-parallel λ-h curves are given by two tests of different tested sample sections, and the intersection point (h c , λ c ) of these two λ-h curves is obtained. , h c is the real lateral heat transfer coefficient of the tested sample at this temperature, and λ c is the longitudinal thermal conductivity of the tested sample at this temperature. 2.根据权利要求1所述的一种直接通电纵向导热系数测试方法，其特征在于，所述被测样品段长度为被测样品直径或厚度的20倍以上。2 . The method for testing longitudinal thermal conductivity with direct current flow according to claim 1 , wherein the length of the measured sample segment is more than 20 times the diameter or thickness of the measured sample. 3 . 3.根据权利要求1所述的一种直接通电纵向导热系数测试方法，其特征在于，步骤(1)所述的被测样品以四电极方式连接在测量电路中，其中外面两电极为电流引线，内部两电极用于电压引线。3. a kind of direct energization longitudinal thermal conductivity testing method according to claim 1 is characterized in that, the tested sample described in step (1) is connected in the measuring circuit by four-electrode mode, and wherein two outer electrodes are current leads , the inner two electrodes are used for voltage leads. 4.根据权利要求1所述的一种直接通电纵向导热系数测试方法，其特征在于，所述步骤(2)包括以下步骤：4. a kind of direct energization longitudinal thermal conductivity testing method according to claim 1, is characterized in that, described step (2) comprises the following steps: (21)直流电流用于加热被测样品段，交流电流用于检测被测样品段的电阻；(21) DC current is used to heat the tested sample segment, and AC current is used to detect the resistance of the tested sample segment; (22)测量被测样品段上的交流电压降，计算出样品段的电阻R；测量被测样品上的直流电压降，计算出在被测样品段中产生的焦耳热UI，并对R和UI进行线性拟合：(22) Measure the AC voltage drop on the sample section under test, and calculate the resistance R of the sample section; measure the DC voltage drop on the sample section under test, calculate the Joule heat UI generated in the sample section under test, and compare R and R and UI for linear fitting: R＝R0+b×UI (1)R=R 0 +b×UI (1) 得到被测样品段在给定温度下的电阻R0和斜率b。Obtain the resistance R 0 and slope b of the sample segment under test at a given temperature. 5.根据权利要求1所述的一种直接通电纵向导热系数测试方法，其特征在于，所述步骤(3)包括以下步骤：5. a kind of direct energization longitudinal thermal conductivity testing method according to claim 1, is characterized in that, described step (3) comprises the following steps: (31)使用不同温度下的R0计算出被测样品段的电阻温度系数α：(31) Calculate the temperature coefficient of resistance α of the sample section under test using R 0 at different temperatures: (32)在每个测量温度下，假设一个侧面换热系数h，由下面公式得到一个对应的导热系数λ：(32) At each measurement temperature, assuming a side heat transfer coefficient h, a corresponding thermal conductivity λ is obtained from the following formula: 其中，As为被测样品段的侧面面积，L为被测样品段长度，P为被测样品段横截面的周长，Ac为被测样品段的横截面面积。Among them, A s is the lateral area of the tested sample segment, L is the length of the tested sample segment, P is the perimeter of the cross-section of the tested sample segment, and A c is the cross-sectional area of the tested sample segment.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111323453A (en) * 2020-03-25 2020-06-23 武汉大学 Method and device for measuring convective heat transfer coefficients of different surface roughness under microscale
CN111537560A (en) * 2020-06-12 2020-08-14 上海上大瑞沪微系统集成技术有限公司 Method and equipment for testing heat conductivity coefficient by using joule self-heating method
CN119064406A (en) * 2024-11-06 2024-12-03 中国科学院合肥物质科学研究院 Thermal conductivity measurement system and thermal conductivity measurement method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101266220A (en) * 2007-03-14 2008-09-17 中国科学院工程热物理研究所 Method and device for measuring liquid thermal conductivity and thermal diffusivity by harmonic detection technology
CN101881741A (en) * 2009-05-08 2010-11-10 清华大学 One-dimensional material thermal conductivity measurement system and its measurement method
CN101782541B (en) * 2009-12-09 2011-10-05 中国科学院工程热物理研究所 Method and device for testing thermophysical properties of solid materials by harmonic method with independent probe
CN102279204A (en) * 2010-06-09 2011-12-14 中国科学院工程热物理研究所 Detection method for thermal conductivity and thermal diffusivity of anisotropic material
RU2654823C1 (en) * 2017-08-22 2018-05-22 Антон Владимирович Шмаков Method of measuring thermal conductivity of solid materials

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101266220A (en) * 2007-03-14 2008-09-17 中国科学院工程热物理研究所 Method and device for measuring liquid thermal conductivity and thermal diffusivity by harmonic detection technology
CN101881741A (en) * 2009-05-08 2010-11-10 清华大学 One-dimensional material thermal conductivity measurement system and its measurement method
CN101782541B (en) * 2009-12-09 2011-10-05 中国科学院工程热物理研究所 Method and device for testing thermophysical properties of solid materials by harmonic method with independent probe
CN102279204A (en) * 2010-06-09 2011-12-14 中国科学院工程热物理研究所 Detection method for thermal conductivity and thermal diffusivity of anisotropic material
RU2654823C1 (en) * 2017-08-22 2018-05-22 Антон Владимирович Шмаков Method of measuring thermal conductivity of solid materials

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
王照亮等: "用3ω法测量非线性KTP晶体各向异性导热系数", 《强激光与粒子束》 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111323453A (en) * 2020-03-25 2020-06-23 武汉大学 Method and device for measuring convective heat transfer coefficients of different surface roughness under microscale
CN111537560A (en) * 2020-06-12 2020-08-14 上海上大瑞沪微系统集成技术有限公司 Method and equipment for testing heat conductivity coefficient by using joule self-heating method
CN119064406A (en) * 2024-11-06 2024-12-03 中国科学院合肥物质科学研究院 Thermal conductivity measurement system and thermal conductivity measurement method

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