SENSOR AND MEASUREMENT METHOD FOR MEASURING HYDROGEN CONTENT IN METAL MELT

Abstract

A sensor and a measurement method for measuring hydrogen content in metal melt. The sensor has a solid proton conductor element, a reference electrode, a quasi-electrode to be measured, a reference compound, a through pipe and an insulating ceramic adhesive. The measurement method has the steps of: (1) inserting the sensor and a corrosion-resistant electrode into the metal melt, and making sure that the solid proton conductor element is fully immersed into the metal melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the reference electrode cable or the metal gas guide pipe to the corrosion-resistant electrode, and measuring a potential difference between the reference electrode and the electrode to be measured; and (3) calculating the hydrogen content S of the metal melt.

Claims

1-10. (canceled)

11. A sensor for measuring hydrogen content in metal melt, comprising: a solid proton conductor element, a reference electrode, a quasi-electrode to be measured, a reference compound, a through pipe and an insulating ceramic adhesive, wherein the through pipe and the solid proton conductor element are connected through the insulating ceramic adhesive to form an inner space, the surface located in the space, of the solid proton conductor element, is an inner surface, and the surface exposed outside is an outer surface; the reference electrode is coated to the inner surface of the solid proton conductor element, and the quasi-electrode to be measured is the outer surface of the solid proton conductor element; the quasi-electrode to be measured is in contact with the metal melt during hydrogen measurement, and the contact surface forms the electrode to be measured; and the reference compound is gas, liquid or solid, is placed in the inner space and is in contact with the reference electrode.

12. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein the sensor further comprises a gas guide pipe and a three-way clamp, wherein when the sensor comprises the gas guide pipe and the three-way clamp, the reference compound is gas, the three-way clamp is connected with an upper part of the through pipe, the gas guide pipe is inserted into the inner space formed by the through pipe, the insulating ceramic adhesive and the solid proton conductor element through the three-way clamp and is connected to the reference electrode, and when a bottom end of the gas guide pipe directly faces to the reference electrode and the solid proton conductor element, the bottom end of the gas guide pipe is a blind end, a side opening thereof acts as a gas outlet.

13. The sensor for measuring hydrogen content in metal melt according to claim 12, wherein the sensor further comprises a reference electrode cable, and when the reference compound is gas, the reference electrode cable is inserted into the through pipe through the three-way clamp, is connected with the reference electrode and is externally connected to a measuring circuit, and the reference electrode cable is metal platinum, gold, silver, nickel-chromium alloy, iron-chromium-aluminum alloy or stainless steel.

14. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein the sensor comprises a reference electrode cable, wherein when the reference compound is liquid or solid, the reference electrode cable penetrates through the insulating ceramic adhesive, is connected with the reference electrode and is externally connected to a measuring circuit, and the reference electrode cable is metal platinum, gold, silver, nickel-chromium alloy, iron-chromium-aluminum alloy or stainless steel.

15. The sensor for measuring hydrogen content in metal melt according to claim 14, wherein when the reference compound is liquid or solid, the sensor further comprises an inert material of Al.sub.2O.sub.3, YSZ or Y.sub.2O.sub.3; and the inert material is stuffed between the reference compound and the insulating ceramic adhesive.

16. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein the solid proton conductor element has a tubular, spherical, flaky, discoid, cubic or cylindrical structure and is made of a perovskite or complex perovskite structure material.

17. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein a material of the reference electrode is silver, platinum or gold.

18. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein a material of the insulating ceramic adhesive is an alumina-based material.

19. The sensor for measuring hydrogen content in metal melt according to claim 11, wherein when the reference compound is gas, liquid or solid, the gas comprises ArH.sub.2, N.sub.2H.sub.2, HeH.sub.2, O.sub.2H.sub.2O or N.sub.2NH.sub.3 gas, which is doped or undoped with one or more inert gases, the liquid comprises LiLiH, and the solid comprises YH, TiH, ZrH or ScH.

20. A method for measuring hydrogen content in metal melt by using the sensor for measuring hydrogen content in metal melt according to claim 11, the method comprising the following steps of: (1) inserting the sensor and a corrosion-resistant electrode into the metal melt, and making sure that the solid proton conductor element is fully immersed into the metal melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the reference electrode cable or the metal gas guide pipe to the corrosion-resistant electrode, and measuring a potential difference between the reference electrode and the electrode to be measured; and (3) calculating the hydrogen content S of the metal melt according to the measured potential difference, a temperature of the metal melt and a saturated solubility of hydrogen in the metal melt.

21. The sensor for measuring hydrogen content in metal melt according to claim 12, wherein the sensor comprises a reference electrode cable, wherein when the reference compound is liquid or solid, the reference electrode cable penetrates through the insulating ceramic adhesive, is connected with the reference electrode and is externally connected to a measuring circuit, and the reference electrode cable is metal platinum, gold, silver, nickel-chromium alloy, iron-chromium-aluminum alloy or stainless steel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which:

[0038] FIG. 1 is the diagram showing the process for measuring hydrogen content in a metal melt by using the sensor of the present invention;

[0039] FIG. 2 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 1 of the present invention;

[0040] FIG. 3 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 2 of the present invention;

[0041] FIG. 4 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 3 of the present invention;

[0042] FIG. 5 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 4 of the present invention;

[0043] FIG. 6 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 5 of the present invention;

[0044] FIG. 7 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 6 of the present invention;

[0045] FIG. 8 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 7 of the present invention; and

[0046] FIG. 9 is the structure diagram of the sensor for measuring hydrogen content in the embodiment 8 of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0047] The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

Embodiment 1

[0048] As shown in FIG. 1 and FIG. 2, the sensor for measuring hydrogen content in aluminum melt comprises a CaZr.sub.0.9In.sub.0.1O.sub.3- solid proton conductor element 1, a reference electrode 2, a quasi-electrode to be measured 6, a reference compound ArH.sub.2, a stainless steel gas guide pipe 3, a corundum through pipe 5, an alumina-based insulating ceramic adhesive 4 and a Teflon three-way clamp 104, wherein the solid proton conductor element 1 adopts a tubular structure and is made of perovskite, one end is sealed by the alumina-based insulating ceramic adhesive 4, the through pipe 5 and the solid proton conductor element 1 are connected through the insulating ceramic adhesive 4 to form an inner space, the surface located in the space, of the solid proton conductor element 1 is an inner surface, and the surface exposed outside is an outer surface; the reference electrode 2 is coated to the inner surface of the solid proton conductor element 1 and the alumina-based insulating ceramic adhesive 4, and the quasi-electrode 6 to be measured is the outer surface of the solid proton conductor element 1; the upper part of the through pipe 5 is connected through the Teflon three-way clamp 104, and one side of the Teflon three-way clamp is provided with a gas outlet 105; the reference compound ArH.sub.2 is introduced into the inner space and is in contact with the reference electrode 2; and the gas guide pipe 3 is inserted into the inner space through the Teflon three-way clamp 104 and is in contact with the reference electrode 2.

[0049] The reference electrode is made of porous platinum.

[0050] For the reference compound ArH.sub.2, the mole hydrogen content is 1.00%.

[0051] The method for measuring hydrogen content in aluminum melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the metal melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the metal gas guide pipe to the graphite corrosion-resistant electrode through a stainless steel wire, and measuring the potential difference between the reference electrode and the electrode to be measured to be 17.3 mV; and (3) calculating the hydrogen content S of the metal melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt, wherein the cell reaction equation and the calculation formula are shown as (4) and (5):

[00005] $\begin{matrix} \frac{1}{2} .Math. H_{2} = {[H]}_{Metal} & (4) \\ .Math. .Math. G = .Math. .Math. G^{} + RT .Math. .Math. \ln .Math. .Math. \frac{a_{[H]}}{\sqrt{p_{H_{2}}^{ref} / p^{}}} = - EF & (5) \\ .Math. .Math. G^{} = - RT .Math. .Math. \ln .Math. .Math. {KS}_{0} & (11) \end{matrix}$

in the formula (11), S.sub.0 is the saturated solubility of hydrogen (ml/100 g), and K is a constant produced by unit transformation. Because the saturated solubility S.sub.0 of most of metals is known thermodynamic data or thermodynamic data which can be calculated, the standard Gibbs free energy G.sup. for hydrogen dissolving in the metal melt can be calculated.

[0052] Because the standard Gibbs free energy G.sup. for hydrogen dissolving in the metal melt is only related to the kind and the temperature of the metal melt and does not change along with hydrogen content in the metal melt, when hydrogen is saturated in the metal melt, the standard free energy G.sup. for hydrogen dissolving in the metal melt is the same as that in unsaturation;

[0053] The formula (11) is put into the formula (5) to obtain:

[00006] $\begin{matrix} S = \exp .Math. .Math. (\ln .Math. .Math. S_{0} .Math. \sqrt{p_{H_{2}}^{ref} / p^{}} - \frac{EF}{RT}) & (14) \end{matrix}$

[0054] The electromotive force E is measured by the potentiometer, and the stabilized hydrogen content of the aluminum melt is calculated to be S=0.103 ml/100 gAl.

Embodiment 2

[0055] The sensor for measuring hydrogen content in aluminum melt is the same as that in the embodiment 1, as shown in FIG. 3. The difference lies in that: the sensor also comprises a reference electrode cable 7 which is made of metal platinum. The reference electrode cable 7 is inserted into the quartz through pipe 5 through the copper three-way clamp 104, is connected to the gold reference electrode 2 and is externally connected to a measuring circuit; the gas guide pipe is made of corundum; the solid proton conductor element 1 is made of CaZr.sub.0.9Sc.sub.0.1O.sub.3-; the three-way clamp 104 is made of copper; the through pipe is made of quartz; and the reference electrode is made of porous gold.

[0056] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the aluminum melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the reference electrode cable to the graphite corrosion-resistant electrode through a platinum wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the metal melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.113 ml/100 gAl.

Embodiment 3

[0057] The sensor for measuring hydrogen content in aluminum melt is the same as that in the embodiment 1, as shown in FIG. 4. The difference lies in that: the solid proton conductor element 1 used in the sensor adopts a flaky structure; the through pipe 5 is made of stainless steel; one end being contact with the proton conductor 1, of the nickel-chromium gas guide pipe 3 is a blind end, a side opening is used as a gas outlet, and the vertical distance between the gas outlet and the top end of the solid proton conductor is 2-5 mm; the gas guide material is made of nickel-chromium alloy; and the reference gas is HeH.sub.2, and the mole hydrogen content is 1.00%.

[0058] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the aluminum melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the nickel-chromium gas guide pipe to the graphite corrosion-resistant electrode through a nickel-chromium wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.109 ml/100 gAl.

Embodiment 4

[0059] The sensor for measuring hydrogen content in aluminum melt is the same as that in the embodiment 3, as shown in FIG. 5. The difference lies in that: the sensor also comprises a reference electrode cable 7 which is made of metal silver. The reference electrode cable 7 is inserted into the through pipe 5 through the stainless steel clamp 104, is connected with the silver reference electrode 2 and is externally connected to a measuring circuit; the through pipe 5 is made of quartz; the gas guide pipe is made of corundum; the reference electrode is made of porous silver; and the reference gas is N.sub.2H.sub.2, and the mole hydrogen content is 1.00%.

[0060] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the metal melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the reference electrode cable to the graphite corrosion-resistant electrode through a silver wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.130 ml/100 gAl.

Embodiment 5

[0061] The sensor for measuring hydrogen content in aluminum melt is the same as that in embodiment 3, as shown in FIG. 6. The difference lies in that: the solid proton conductor element 1 used in the sensor adopts a spherical structure.

[0062] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the aluminum melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the gas guide pipe to the graphite corrosion-resistant electrode through a stainless steel wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.123 ml/100 gAl.

Embodiment 6

[0063] The sensor for measuring hydrogen content in aluminum melt is the same as that in embodiment 5, as shown in FIG. 7. The difference lies in that: the sensor also comprises a reference electrode cable 7 which is made of stainless steel. The reference electrode cable 7 is inserted into the through pipe 5 through the Teflon three-way clamp 104, is connected to the reference electrode 2 and is externally connected to a measuring circuit; and the gas guide pipe is made of corundum.

[0064] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the aluminum melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and the reference electrode cable to the corrosion-resistant electrode through a stainless steel wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.099 ml/100 gAl.

Embodiment 7

[0065] As shown in FIG. 8, the sensor for measuring hydrogen content in aluminum melt comprises a solid proton conductor element 1, a reference electrode 2, an electrode to be measured, a platinum-wire cable 7, a solid reference compound 8, a corundum through pipe 5, an alumina-based ceramic adhesive 4 and an Al.sub.2O.sub.3 inert material 9, wherein the solid proton conductor element 1 adopts a tubular structure and is made of CaZr.sub.0.9In.sub.0.1O.sub.3-, one end is sealed by using the alumina-based ceramic adhesive 4, the through pipe 5 and the solid proton conductor element 1 are connected through the insulating ceramic adhesive 4 to form an inner space, the surface located in the inner space, of the solid proton conductor element 1 is an inner surface, and the surface exposed outside is an outer surface; the reference electrode 2 is coated to the inner surface of the solid proton conductor element 1, and the quasi-electrode 6 to be measured is the outer surface of the solid proton conductor element 1; the bottom of the solid proton conductor element 1 is stuffed with the Al.sub.2O.sub.3 inert material 9, the upper part is stuffed with the YH system solid reference compound 8, the reference compound 8 is in contact with the reference electrode 2 and the platinum-wire cable 7, the Al.sub.2O.sub.3 inert material 9 is stuffed to a space above the reference compound 8, and then the reference compound 8 is sealed by using the alumina-based ceramic adhesive 4 and is connected with the corundum through pipe 5; and the platinum-wire cable 7 penetrates through the insulating ceramic adhesive 4, is connected with the reference electrode 2 and is externally connected to a measuring circuit.

[0066] The reference electrode is made of platinum.

[0067] The reference compound is a YH system solid, and the mole hydrogen content in equilibrium atmosphere of the YH system solid at 750 C. is 0.11%.

[0068] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element 1 is fully immersed into the metal melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and a platinum-wire cable to the graphite corrosion-resistant electrode through a platinum wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.107 ml/100 gAl.

Embodiment 8

[0069] The sensor for measuring hydrogen content in aluminum melt is the same as that in the embodiment 7, as shown in FIG. 9. The difference lies in that: the solid proton conductor element 1 used in the sensor adopts a flaky structure and is made of CaZr.sub.0.9Sc.sub.0.1O.sub.3-; the inert material is Y.sub.2O.sub.3; the reference compound is a ScH system solid, and the mole hydrogen content in equilibrium atmosphere of the ScH system solid at 750 C. is 0.25%.

[0070] The method for measuring hydrogen content in metal melt by using the sensor comprises the following process steps of (1) inserting the sensor and a graphite corrosion-resistant electrode into the aluminum melt of 750 C., and making sure that the solid proton conductor element is fully immersed into the aluminum melt, the quasi-electrode to be measured is in direct contact with the metal melt and the contact surface is the electrode to be measured; (2) connecting a potentiometer and a cable to the graphite corrosion-resistant electrode through a platinum wire, and measuring the potential difference between the reference electrode and the electrode to be measured; and (3) calculating the stabilized hydrogen content S of the aluminum melt according to the measured potential difference, the temperature of the metal melt and the saturated solubility of hydrogen in the metal melt to be 0.143 ml/100 gAl.

SENSOR AND MEASUREMENT METHOD FOR MEASURING HYDROGEN CONTENT IN METAL MELT

Inventors

Cpc classification

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G01N33/005

PHYSICS

Classification Explorer

G01N27/4114

PHYSICS

Classification Explorer

G01N27/30

PHYSICS

Classification Explorer

G01N27/301

PHYSICS

Classification Explorer

G01N33/2025

PHYSICS

International classification

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G01N27/411

PHYSICS

Classification Explorer

G01N33/00

PHYSICS

Abstract

Claims

Description