Pt-based high-temperature alloy material for spark plug and preparation method of Pt-based high-temperature alloy material

Abstract

The invention discloses a Pt-based high-temperature alloy material for a spark plug and a preparation method of the Pt-based high-temperature alloy material, the Pt-based high-temperature alloy material comprises the following components in percentage by weight: 0.01%-0.15% of Y, 0.01%-0.15% of Sc, 5%-15% of Ru and the balance of Pt, and the total adding amount of the two elements of Y and Sc is not higher than 0.15%. In order to further improve the performance of the Pt-based alloy for the spark plug, control the alloy cost and improve the convenience of the alloy preparation process, the alloy is strengthened by simultaneously adding the Y and Sc elements from the alloy component design, and the alloy cost is reduced while the high melting point of the alloy is ensured by adding the Ru element. And the performance of the alloy is further improved through ordered heat treatment.

Description

Technical Field

[0001] The invention relates to the technical field of spark plug electrodes, and in particular to a Pt-based high-temperature alloy material for a spark plug and a preparation method thereof. Background Art

[0002] The Pt element has a high melting point and stable chemical properties. It is an ideal high-temperature material and a high-temperature alloy material that is widely used in the spark plug field. However, Pt has low high-temperature strength and low resistance to welding. Usually, elements such as Ir, Rh, Ni, and Ru are added to strengthen the alloy to improve the alloy's comprehensive high-temperature performance. In general application scenarios, Ir and Rh have better strengthening effects, but the cost of alloy materials is relatively high and has not been widely used.

[0003] Document 1, CN104674048A reports a Pt-Ru based high temperature alloy material and a preparation method thereof: the main elements of the alloy are Pt and Ru, and by adding one or more of Re, Al, W, Ta, Nb, Ti, Zr, Cr, and Ni, and then adding one or more of the rare earth elements La, Nd, Pr, Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ce, and Th, quaternary, quinary, and hexavalent alloys are finally prepared.

[0004] Document 2, CN114107723A reports a crucible for drawing glass fiber, a Pt-based high-temperature alloy and a preparation method thereof: the Pt-based high-temperature alloy contains 0.5wt%-20wt% Ru and also contains Me element, wherein the Me element is at least one of Cr, Nd, Sm, Sc, Er, Dy and Ta, and the content thereof is 0.05wt%-1.5wt%. A dense oxide film is formed on the surface of the alloy of the invention.

[0005] The alloying element content of document 1 is high, which makes it difficult to obtain uniform alloying elements during the alloy preparation process. The alloy of document 2 forms a dense oxide film on its surface, which affects the electrical conductivity and is not suitable for use as a spark plug electrode material. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above problems existing in the existing Pt-based high-temperature alloy materials for spark plugs and the preparation methods thereof, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to provide a Pt-based high-temperature alloy material for spark plugs and a preparation method thereof, which starts from the alloy composition design, strengthens the alloy by adding Y and Sc elements at the same time, reduces the alloy cost while ensuring the high melting point of the alloy by adding Ru elements, and further improves the alloy performance through ordered heat treatment.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: a Pt-based high-temperature alloy material for a spark plug, comprising:

[0010] The addition amounts of Y and Sc are 0.01% to 0.15% by weight, the addition amount of Ru is 5% to 15%, and the balance is Pt.

[0011] As a preferred solution of the Pt-based high-temperature alloy material for spark plugs described in the present invention, the total addition amount of the two elements Y and Sc is not higher than 0.15%.

[0012] A method for preparing a Pt-based high-temperature alloy material for a spark plug comprises the following steps:

[0013] Step 1, Y and Sc are added in amounts of 0.01% to 0.15% by weight respectively, the total amount of the two elements added is not higher than 0.15%, Ru is added in an amount of 5-15%, and the balance is Pt;

[0014] Step 2: Y, Sc, Ru, and Pt elements are placed in a crucible, and smelted in a vacuum high frequency furnace. After smelting, the elements are poured into a water-cooled copper mold to obtain an ingot;

[0015] Step 3: homogenizing the ingot at 1250°C for 4 hours;

[0016] Step 4: hot forging the ingot at 1250°C to obtain a 6mm diameter bar;

[0017] Step 5: The rod obtained in step 4 is rolled on a semicircular pass rolling mill to obtain a wire with a diameter of 2 mm. When the total deformation reaches 45%, annealing is performed at 1250° C. for 45 minutes, and quenching is performed in ice salt water after annealing.

[0018] Step 6: The wire obtained in step 5 is drawn on a multi-mode wire drawing machine to a finished product size of 0.3-0.5 mm; when the deformation per pass does not exceed 8% and the total deformation reaches 45%, annealing is performed at 1200°C for 30 minutes, and quenching is performed in ice salt water after annealing;

[0019] Step 7: Orderly heat treatment: The hard wire drawn to the finished size is subjected to orderly heat treatment at 750-780°C for 30 minutes.

[0020] As a preferred solution of the method for preparing the Pt-based high-temperature alloy material for spark plugs of the present invention, the crucible is a high-purity zirconia crucible or a cold crucible suspension melting is adopted.

[0021] As a preferred solution of the method for preparing the Pt-based high-temperature alloy material for spark plugs according to the present invention, the hot forging in step 4 adopts slow hot forging.

[0022] As a preferred solution of the method for preparing the Pt-based high-temperature alloy material for spark plugs of the present invention, the 2 mm wire obtained in step 5 has a deformation amount of no more than 12% in each rolling process.

[0023] Beneficial effects of the present invention: The Pt-based high-temperature alloy material for spark plugs of the present invention has good comprehensive performance, low cost, and convenient production and processing. In order to further improve the performance of the Pt-based alloy for spark plugs, control the alloy cost, and improve the convenience of the alloy preparation process, the present invention starts from the alloy composition design, strengthens the alloy by adding Y and Sc elements at the same time, and reduces the alloy cost by adding Ru elements to ensure the high melting point of the alloy. The alloy performance is further improved by ordered heat treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0025] Figure 1 This is an influence diagram of hardness of Example 14 and Comparative Example 2 of the Pt-based high-temperature alloy material for spark plugs and its preparation method of the present invention.

[0026] Figure 2 This is a metallographic structure diagram of Example 14 of the Pt-based high-temperature alloy material for spark plugs and the preparation method thereof of the present invention, annealed at 1250° C. and for 45 minutes. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0030] Reference Figure 1 -2. A method for preparing a Pt-based high-temperature alloy material for a spark plug, comprising the following steps:

[0031] Step 1, Y and Sc are added in amounts of 0.01% to 0.15% by weight respectively, the total amount of the two elements added is not higher than 0.15%, Ru is added in an amount of 5-15%, and the balance is Pt;

[0032] Step 2: Y, Sc, Ru, and Pt elements are placed in a crucible, and smelted in a vacuum high frequency furnace. After smelting, the elements are poured into a water-cooled copper mold to obtain an ingot;

[0033] Step 3: homogenizing the ingot at 1250°C for 4 hours;

[0034] Step 4: hot forging the ingot at 1250°C to obtain a 6mm diameter bar;

[0035] Step 5: The rod obtained in step 4 is rolled on a semicircular pass rolling mill to obtain a wire with a diameter of 2 mm. When the total deformation reaches 45%, annealing is performed at 1250° C. for 45 minutes, and quenching is performed in ice salt water after annealing.

[0036] Step 6: The wire obtained in step 5 is drawn on a multi-mode wire drawing machine to a finished product size of 0.3-0.5 mm; when the deformation per pass does not exceed 8% and the total deformation reaches 45%, annealing is performed at 1200°C for 30 minutes, and quenching is performed in ice salt water after annealing;

[0037] Step 7: Orderly heat treatment: The hard wire drawn to the finished size is subjected to orderly heat treatment at 750-780°C for 30 minutes.

[0038] Specific embodiments and comparative examples are as follows:

[0039] Example 1

[0040] Step 1: Prepare the ingredients by weight percentage: Y: 0.14%, Sc: 0.01%, Ru: 5%, Pt balance;

[0041] Step 2: Vacuum melting and casting in a water-cooled copper mold to obtain an ingot with a diameter of 17 mm;

[0042] Step 3: The ingot is subjected to homogenization heat treatment at 1250°C for 4 hours;

[0043] Step 4: The ingot is hot forged at 1250°C to obtain a 6mm diameter bar;

[0044] Step 5: The bar is rolled on a semicircular pass mill to obtain a wire with a diameter of 2 mm. The deformation of each rolling process does not exceed 12%. When the total deformation reaches 45%, annealing is performed at 1250°C for 45 minutes. After annealing, quenching is performed in ice salt water.

[0045] Step 6: The wire is drawn on a multi-mode wire drawing machine to a finished size of 0.3-0.5 mm. When the deformation per pass does not exceed 8% and the total deformation reaches 45%, annealing is performed at 1200°C for 30 minutes, and quenching is performed in ice salt water after annealing.

[0046] Step 7: Orderly heat treatment: the hard wire pulled to the finished size is subjected to ordering heat treatment at 750℃ for 30 minutes.

[0047] Example 2

[0048] Step 1: Prepare the ingredients by weight percentage: Y: 0.09%, Sc: 0.01%, Ru: 5%, Pt balance;

[0049] The remaining steps are the same as in Example 1.

[0050] Example 3

[0051] Step 1: Prepare the ingredients by weight percentage: Y: 0.01%, Sc: 0.01%, Ru: 5%, Pt balance;

[0052] The remaining steps are the same as in Example 1.

[0053] Example 4

[0054] Step 1: Prepare the ingredients by weight percentage: Y: 0.01%, Sc: 0.14%, Ru: 5%, Pt balance;

[0055] The remaining steps are the same as in Example 1.

[0056] Example 5

[0057] Step 1: Mix the ingredients by weight percentage: Y: 0.01%, Sc: 0.09%, Ru: 5%, Pt balance;

[0058] The remaining steps are the same as in Example 1.

[0059] Example 6

[0060] Step 1: Prepare the ingredients by weight percentage: Y: 0.01%, Sc: 0.14%, Ru: 8%, Pt balance;

[0061] The remaining steps are the same as in Example 1.

[0062] Example 7

[0063] Step 1: Prepare the ingredients by weight percentage: Y: 0.14%, Sc: 0.01%, Ru: 8%, Pt balance;

[0064] The remaining steps are the same as in Example 1.

[0065] Example 8

[0066] Step 1: Prepare the ingredients by weight percentage: Y: 0.05%, Sc: 0.07%, Ru: 8%, Pt balance;

[0067] The remaining steps are the same as in Example 1.

[0068] Example 9

[0069] Step 1: Mix the ingredients by weight percentage: Y: 0.01%, Sc: 0.14%, Ru: 12%, and Pt as the balance;

[0070] Steps 2 to 6 are the same as in Example 1;

[0071] Step 7: Orderly heat treatment: the hard wire pulled into finished size is subjected to ordering heat treatment at 780°C for 30 minutes.

[0072] Example 10

[0073] Step 1: Prepare the ingredients by weight percentage: Y: 0.14%, Sc: 0.01%, Ru: 12%, Pt balance;

[0074] The remaining steps are the same as in Example 9.

[0075] Embodiment 11

[0076] Step 1: Mix the ingredients by weight percentage: Y: 0.07%, Sc: 0.05%, Ru: 12%, and Pt as the balance;

[0077] The remaining steps are the same as in Example 9.

[0078] Example 12

[0079] Step 1: Prepare the ingredients by weight percentage: Y: 0.01%, Sc: 0.14%, Ru: 15%, Pt balance;

[0080] The remaining steps are the same as in Example 9.

[0081] Example 13

[0082] Step 1: Prepare the ingredients by weight percentage: Y: 0.14%, Sc: 0.01%, Ru: 15%, and Pt as the balance; the remaining steps are the same as in Example 9.

[0083] Embodiment 14

[0084] Step 1: Prepare the ingredients by weight percentage: Y: 0.06%, Sc: 0.07%, Ru: 15%, and Pt as the balance; the remaining steps are the same as in Example 9.

[0085] Comparative Example 1

[0086] Step 1: Mix the ingredients by weight percentage, Ru: 5%, Pt balance;

[0087] Step 2 to step 6 are the same as in Example 1

[0088] Comparative Example 2

[0089] Step 1: Mix the ingredients by weight percentage, Ru: 15%, Pt balance;

[0090] Step 2 to step 6 are the same as in Example 1

[0091] Comparative Example 3

[0092] Step 1: Mix the ingredients by weight percentage: Y: 0.13%, Ru: 5%, Pt balance;

[0093] Step 2 to step 7 are the same as in Example 1

[0094] Comparative Example 4

[0095] Step 1: Mix the ingredients by weight percentage: Y: 0.13%, Ru: 15%, Pt balance;

[0096] Step 2 to step 7 are the same as in Example 9

[0097] Comparative Example 5

[0098] Step 1: Mix the ingredients by weight percentage: Sc: 0.13%, Ru: 5%, Pt balance;

[0099] Step 2 to step 7 are the same as in Example 1

[0100] Comparative Example 6

[0101] Step 1: Mix the ingredients by weight percentage: Sc: 0.13%, Ru: 15%, Pt balance;

[0102] Step 2 to step 7 are the same as in Example 9

[0103] The processing properties of the embodiments and comparative examples are shown in Table 1.

[0104] Table 1

[0105]

[0106]

[0107] The strength and hardness comparison of the embodiment and the comparative example are shown in Table 2.

[0108] Table 2

[0109]

[0110]

[0111] Among them, the effect of the ordering heat treatment temperature (heat treatment time is 30 minutes) on the hardness of Example 14 and Comparative Example 2 is shown in Figure 1 .

[0112] In order to further improve the performance of Pt-based alloys used in spark plugs, control alloy costs, and improve the convenience of alloy preparation, the present invention starts from the design of alloy composition, strengthens the alloy by adding Y and Sc elements at the same time, and reduces alloy costs by adding Ru elements to ensure a high melting point of the alloy. The alloy performance is further improved by ordered heat treatment.

[0113] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A Pt-based high-temperature alloy material for a spark plug, characterized in that: include: The addition amounts of Y and Sc are 0.01% to 0.15% by weight, the addition amount of Ru is 5% to 15%, and the balance is Pt.

2. The Pt-based high-temperature alloy material for spark plugs according to claim 1, characterized in that: The total addition amount of the two elements Y and Sc is not higher than 0.15%.

3. A method for preparing a Pt-based high-temperature alloy material for a spark plug, characterized in that: The following steps are involved: Step 1, Y and Sc are added in amounts of 0.01% to 0.15% by weight respectively, the total amount of the two elements added is not higher than 0.15%, Ru is added in an amount of 5-15%, and the balance is Pt; Step 2: Y, Sc, Ru, and Pt elements are placed in a crucible, and smelted in a vacuum high frequency furnace. After smelting, the elements are poured into a water-cooled copper mold to obtain an ingot; Step 3: homogenizing the ingot at 1250°C for 4 hours; Step 4: hot forging the ingot at 1250°C to obtain a 6mm diameter bar; Step 5: The rod obtained in step 4 is rolled on a semicircular pass rolling mill to obtain a wire with a diameter of 2 mm. When the total deformation reaches 45%, annealing is performed at 1250° C. for 45 minutes, and quenching is performed in ice salt water after annealing. Step 6: The wire obtained in step 5 is drawn on a multi-mode wire drawing machine to a finished product size of 0.3-0.5 mm; when the deformation per pass does not exceed 8% and the total deformation reaches 45%, annealing is performed at 1200°C for 30 minutes, and quenching is performed in ice salt water after annealing; Step 7: Orderly heat treatment: The hard wire drawn to the finished size is subjected to orderly heat treatment at 750-780°C for 30 minutes.

4. The method for preparing a Pt-based high-temperature alloy material for a spark plug according to claim 3, characterized in that: The crucible is a high-purity zirconia crucible or a cold crucible for suspension smelting.

5. The method for preparing a Pt-based high-temperature alloy material for a spark plug according to claim 3, characterized in that: The hot forging in step 4 adopts slow hot forging.

6. The method for preparing a Pt-based high-temperature alloy material for a spark plug according to claim 1, characterized in that: The 2 mm wire obtained in step 5 has a deformation amount of no more than 12% in each rolling process.

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