阅读说明：本技术 一种具有良好高温耐久烧蚀性能的铱镍合金火花塞中心电极材料及其制备方法 (Iridium-nickel alloy spark plug center electrode material with good high-temperature durable ablation performance and preparation method thereof ) 是由 李旸 马梦一 周川 于 2020-12-14 设计创作，主要内容包括：本发明公开一种具有良好高温耐久烧蚀性能的铱镍合金中心电极材料的制备方法,属于火花塞电极材料技术领域。本发明所述方法是：首先,按质量百分比称取Ni和Ir,加入锆、铝、钨,混合均匀后置于真空环境下；然后,对混合物进行加热,获得合金液,并合金液浇入冶炼模具中进行铸造；最后所得合金铸锭进行均匀化处理,制备出中心电极材料。该材料可作为火花塞电极材料的中心电极；本发明不仅大量使用价格相对廉价的Ni作为原料,而且还有制备工艺简单以及对设备要求不高等优点,使其制备成本低适合于规模化生产；所制备的IrNi合金火花塞中心电极材料,不仅具有加工性能好和抗氧化性能强等特点,而且还有具有良好的高温耐久烧蚀性能。(The invention discloses a preparation method of an iridium-nickel alloy central electrode material with good high-temperature durable ablation performance, and belongs to the technical field of spark plug electrode materials. The method comprises the following steps: firstly, weighing Ni and Ir according to mass percent, adding zirconium, aluminum and tungsten, uniformly mixing, and placing in a vacuum environment; then, heating the mixture to obtain alloy liquid, and pouring the alloy liquid into a smelting mould for casting; and finally, carrying out homogenization treatment on the obtained alloy ingot to prepare the central electrode material. The material can be used as a center electrode of a spark plug electrode material; the invention not only uses a large amount of Ni with relatively low price as raw materials, but also has the advantages of simple preparation process, low requirement on equipment and the like, so that the preparation cost is low and the invention is suitable for large-scale production; the prepared IrNi alloy spark plug center electrode material not only has the characteristics of good processing performance, strong oxidation resistance and the like, but also has good high-temperature durable ablation performance.)

1. A preparation method of an iridium nickel (IrNi) alloy central electrode material with good high-temperature durable ablation performance is characterized by comprising the following steps:

(1) weighing Ni, Ir, Zr, Al and W according to the mass percent, uniformly mixing, placing in a crucible, and putting in a vacuum furnace to prepare a mixture;

(2) heating and smelting the mixture prepared in the step (1) to obtain alloy liquid;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting to obtain an alloy ingot;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) manufacturing the alloy processed in the step (4) into a center electrode of a spark plug;

wherein the mass percentage of Ni, Ir, Zr, Al and W in the step (1) is 39-74: 25-60: 0.2-0.4: 0.3-0.6: 0.1-0.2;

wherein, the vacuum furnace in the step (1) is vacuumized to the vacuum degree of 3.0 multiplied by 10^-3MPa。

2. The method for preparing the iridium-nickel alloy central electrode material with good high-temperature durable ablation performance as claimed in claim 1, wherein a protective gas is filled into the vacuum furnace.

3. The method for preparing the iridium-nickel alloy central electrode material with good high-temperature durable ablation performance as claimed in claim 2, wherein the protective gas is argon.

4. The method for preparing the iridium-nickel alloy central electrode material with good high-temperature durable ablation performance as claimed in claim 2, wherein protective gas is filled into the vacuum furnace until the vacuum degree is 0.5 MPa.

5. The method for preparing the iridium-nickel alloy central electrode material with good high-temperature durable ablation performance as claimed in claim 4, wherein protective gas is charged into a vacuum furnace until the vacuum degree is 0.5MPa, and the vacuum and gas charging are repeated for 3 times to prepare a mixture.

6. The method for preparing the iridium-nickel alloy central electrode material with good high-temperature durable ablation performance as claimed in claim 1, wherein the mixture in the step (2) is subjected to hot melting at a temperature of 2300-2350 ℃.

7. The preparation method of the iridium-nickel alloy center electrode material with good high-temperature durable ablation performance as claimed in claim 6, wherein the temperature is kept for 10min at a rotation speed of 500r/min after smelting.

8. An iridium-nickel alloy center electrode material having good high temperature durable ablation properties prepared according to the method of any one of claims 1-7.

[ technical field ] A method for producing a semiconductor device

The invention belongs to the technical field of spark plug electrode materials, and particularly relates to an iridium-nickel alloy central electrode material with good high-temperature durable ablation performance and a preparation method thereof.

[ background of the invention ]

Spark plugs are important components of gasoline engine ignition systems that introduce high voltage electricity into the combustion chamber and cause it to jump the electrode gap to create a spark that ignites the combustible mixture in the cylinder. FIG. 1 is a schematic electrode diagram of a spark plug consisting essentially of a center electrode (1 mm) welded to a base, where the center electrode is a key component of the spark plug. Good center electrode materials not only require the materials to have good processability, oxidation resistance and lower manufacturing cost, but also require the materials to have good high-temperature durable ablation performance to meet the harsh working environment of the center electrode.

Currently, the materials of the central electrode all use noble metals as main components. The iridium has the advantages of high melting point, high strength, high conductivity, strong corrosion resistance and the like, and the use of the iridium or the iridium alloy as the center electrode material of the spark plug can improve the ignition performance and the fuel economy of the engine, prolong the service life of the engine and reduce the emission of harmful substances. Iridium is therefore an ideal source material for spark plug electrodes. Common iridium or iridium alloy spark plug center electrode materials mainly comprise iridium (Ir) and iridium-rhodium alloy (IrRh)₁₀) Iridium rhodium tungsten zirconium (IrRhWZr, where Rh, 2.5% wt; w, 0.3% wt; zr, 50-600ppm) and iridium rhodium ruthenium nickel (IrRhRuNi, where Rh, 3% wt; ru, 6% wt; ni, 1% wt), etc. However, these center electrode materials require the use of large amounts of Ir and even certain amounts of Rh, both noble metals being 43 ten thousand and 300 ten thousand, respectively. This makes the price of a spark plug using iridium or an iridium alloy as the center electrode prohibitive. Therefore, the content of cheap metal is increased while the performance of the iridium alloy center electrode is ensured to be attenuated, and the method has important significance for reducing the price of the spark plug.

IrNi alloy with high Ni content (Ni content is 20-80 wt%) has the characteristics of processability, low cost, good oxidation resistance and the like, but the poor high-temperature durable ablation performance limits the use of the IrNi alloy as a spark plug central electrode material. Because the working environment of the center electrode is high-temperature and high-pressure acid-base environment when the center electrode is ignited at high temperature, the high-temperature durable ablation performance of the center electrode is mainly reflected on two performances of the material: (1) the material should have high temperature ablation resistance and (2) acid and alkali corrosion resistance at high temperatures. Therefore, the improvement of the high-temperature durable ablation performance of the IrNi alloy with high Ni content is of great significance for reducing the cost of the central electrode material.

[ summary of the invention ]

The invention aims to overcome the defects of the prior art, and a certain amount of Al, Zr and W is added into an IrNi alloy material with high Ni content to prepare a novel iridium alloy center electrode material which has good processing performance, high-temperature oxidation resistance, low cost and good high-temperature durable ablation performance and a preparation method thereof.

The invention adopts the following technical scheme:

a preparation method of an iridium nickel (IrNi) alloy central electrode material with good high-temperature durable ablation performance comprises the following steps:

(1) weighing Ni, Ir, Zr, Al and W according to the mass percent, uniformly mixing, placing in a crucible, and putting in a vacuum furnace to prepare a mixture;

(2) heating and smelting the mixture prepared in the step (1) to obtain alloy liquid;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting to obtain an alloy ingot;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) and (4) manufacturing the alloy processed in the step (4) into a center electrode of the spark plug.

Furthermore, the mass percentage of Ni, Ir, Zr, Al and W in the step (1) is 39-74: 25-60: 0.2-0.4: 0.3-0.6: 0.1-0.2.

Further, in the step (1), the vacuum furnace is vacuumized to the vacuum degree of 3.0 multiplied by 10^-3MPa。

Further, protective gas is filled into the vacuum furnace.

Further, the protective gas is argon.

Further, protective gas is charged into the vacuum furnace until the vacuum degree is 0.5 MPa.

Further, protective gas is filled into the vacuum furnace until the vacuum degree is 0.5MPa, and the vacuum furnace is repeatedly vacuumized and filled with gas for 3 times to prepare a mixture.

Further, the mixture in the step (2) is heated to the temperature of 2300-.

Further, after smelting, the temperature is kept for 10min at the rotating speed of 500 r/min.

The invention has the beneficial effects that:

(1) in the present invention, aluminum (Al) and zirconium (Zr) are easily concentrated on the surface of the material due to their low density, and alumina (Al) is formed₂O₃) And zirconium oxide (ZrO)₂) And (5) passivating the film. The passivation films can better protect the material and improve the corrosion resistance of the material, thereby improving the preparation of the center electrode by using the material. For example, although Zr has a melting point of 1600 ℃, Zr on the center electrode is easily oxidized after ignition of the spark plug to form ZrO having a melting point of 2600 ℃₂In addition, experiments show that the corrosion resistance of the material can be improved by adding low-content tungsten (W) into the material, so that the high-temperature durable ablation performance of the IrNi alloy central electrode material with high Ni content can be synergistically improved by adding a certain amount of Al, Zr and W into the IrNi alloy central electrode material with high Ni content.

(2) According to the invention, a certain amount of Al, Zr and W is added into the IrNi alloy material with high Ni content to prepare the novel iridium alloy material.

(3) Because the material of the invention has good high-temperature durable ablation performance, the IrNi alloy material with high Ni content can be used as the electrode material of the spark plug.

(4) The method has the advantages of simple process, low requirement on equipment, low cost and good industrial application prospect.

[ description of the drawings ]

FIG. 1 is a schematic view of a spark plug electrode;

FIG. 2 is a graph showing the effect of the IrNi alloy center electrode material prepared in example 1 after the cathodic ignition test;

FIG. 3 is a graph showing the effect of IrNi alloy center electrode material prepared in example 1 after anode ignition test;

FIG. 4 shows the hot spark erosion rate (cathode) of the IrNi alloy center electrode material prepared in example 1 of the present invention;

FIG. 5 shows the hot spark erosion rate (anode) of the IrNi alloy central electrode material prepared in example 1 of the present invention;

FIG. 6 is a graph of the percent mass loss after 50 hours of isothermal testing of IrNi alloy center electrode materials prepared in examples 1-8 of the present invention;

FIG. 7 is a graph comparing the hot spark corrosion rates (cathode) after 100 hours, 500 hours and 1000 hours for IrNi alloy center electrode materials prepared in examples 1-8 of the present invention (samples No. 1 to 8 in the graph represent IrNi alloy center electrode materials prepared in examples 1-8, respectively);

FIG. 8 is a graph comparing the hot spark corrosion rates (anodes) of IrNi alloy central electrode materials prepared in examples 1-8 of the present invention after 100 hours, 500 hours, and 1000 hours (samples No. 1 to 8 in the graph represent IrNi alloy central electrode materials prepared in examples 1-8, respectively).

[ detailed description ] embodiments

The invention will be described in more detail with reference to the following figures and examples, but the scope of the invention is not limited thereto.

Example 1

Iridium-nickel (Ir) with good high-temperature durable ablation performance₂₅Ni₇₄Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 74g of Ni and 25g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, putting in a vacuum furnace, and putting the vacuum furnaceVacuum pumping is carried out until the vacuum degree is 3.0 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 0.5MPa, and repeatedly vacuumizing and filling gas for 3 times;

(2) heating the vacuum furnace to the temperature of 2300 ℃, starting timing after the metal is melted, stirring at the rotating speed of 500r/min, and keeping the temperature for 10 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in the step (4) is made into a center electrode of a spark plug, and the center electrode is subjected to an ignition experiment, so that the electrode has good high-temperature durable ablation performance, as shown in figures 2-8.

Example 2

Iridium-nickel (Ir) with good high-temperature durable ablation performance₃₀Ni₆₉Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 69g of Ni and 30g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, putting in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.0 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 1MPa, and repeatedly vacuumizing and filling gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 3

Has good heightIridium nickel (Ir) with temperature durable ablation performance₃₀Ni₆₇Zr_1.3AI_1.3W_0.4) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 67g of Ni and 30g of Ir according to mass percent, adding 1.3g of zirconium (Zr), 1.3g of aluminum (Al) and 0.4g of tungsten (W), uniformly mixing, placing in a crucible, putting in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.5 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 0.8MPa, and repeatedly vacuumizing and filling gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 500r/min, and maintaining the temperature for 20 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 4

Iridium-nickel (Ir) with good high-temperature durable ablation performance₃₅Ni₆₄Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 64g of Ni and 35g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible and putting in a vacuum furnace. Vacuumizing the vacuum furnace to the vacuum degree of 2.0 multiplied by 10^-3And (5) introducing argon protective gas into the vacuum furnace until the vacuum degree is 1 MPa. Repeatedly vacuumizing and inflating the gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 5

Iridium-nickel (Ir) with good high-temperature durable ablation performance₄₀Ni₅₉Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 59g of Ni and 40g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, placing in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.0 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 1MPa, and repeatedly vacuumizing and filling gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 6

Iridium-nickel (Ir) with good high-temperature durable ablation performance₅₀Ni₄₉Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 49g of Ni and 50g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, putting in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.0 multiplied by 10^-3MPa, then filling argon protective gas into the vacuum furnaceRepeatedly vacuumizing and inflating the gas for 5 times until the vacuum degree is 1 MPa;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 7

Iridium-nickel (Ir) with good high-temperature durable ablation performance₆₀Ni₃₉Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 39g of Ni and 60g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, placing in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.0 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 1MPa, and repeatedly vacuumizing and filling gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Example 8

Iridium-nickel (Ir) with good high-temperature durable ablation performance₇₀Ni₂₉Zr_0.4Al_0.4W_0.2) The preparation method of the alloy center electrode material specifically comprises the following steps:

(1) weighing 70g of Ni and 29g of Ir according to the mass percent, adding 0.4g of zirconium (Zr), 0.4g of aluminum (Al) and 0.2g of tungsten (W), uniformly mixing, placing in a crucible, putting in a vacuum furnace, and vacuumizing the vacuum furnace until the vacuum degree is 2.0 multiplied by 10^-3Introducing argon protective gas into the vacuum furnace until the vacuum degree is 1MPa, and repeatedly vacuumizing and filling gas for 5 times;

(2) heating the vacuum furnace to 2350 deg.C, timing when the metal melts, stirring at 400r/min, and maintaining the temperature for 15 min;

(3) pouring the alloy liquid obtained in the step (2) into a smelting mould for casting;

(4) homogenizing the alloy ingot obtained in the step (3);

(5) the alloy treated in step (4) was fabricated into a center electrode of a spark plug, and the center electrode was subjected to an ignition test, which revealed that the electrode had good high-temperature durable ablation properties, as shown in fig. 6-8.

Comparative example 1

The preparation method of the center electrode material was substantially the same as that of example 7, except that zirconium (Zr), aluminum (Al) and tungsten (W) were absent from the raw materials.

Comparative example 2

The same procedure was followed as in example 7 except that the starting material was absent of zirconium (Zr).

Comparative example 3

The same procedure was followed as in example 7 except that aluminum (Al) was absent from the starting materials.

Comparative example 4

The preparation method of the center electrode material was substantially the same as that of example 7, except that tungsten (W) was absent from the raw materials.

The results of the ignition experiments conducted on the center electrodes prepared in comparative examples 1 to 4 show that none of the center electrodes prepared in comparative examples 1 to 4 had good high temperature durable ablation performance, while the center electrode material electrode prepared in example 7 had good heightThe reason for the temperature-resistant ablation property is that in the present invention, aluminum (Al) and zirconium (Zr) are easily concentrated on the surface of the material due to their low density, and alumina (Al) is formed₂O₃) And zirconium oxide (ZrO)₂) And (5) passivating the film. The passivation films can better protect the material and improve the corrosion resistance of the material, thereby improving the preparation of the center electrode by using the material. For example, although Zr has a melting point of 1600 ℃, Zr on the center electrode is easily oxidized after ignition of the spark plug to form ZrO having a melting point of 2600 ℃₂The surface passivation film can protect the central electrode from being corroded, and in addition, the corrosion resistance of the material can be improved by adding low-content tungsten (W) into the material, so that the high-temperature durable ablation performance of the IrNi alloy central electrode material can be synergistically improved by adding certain amounts of Al, Zr and W into the IrNi alloy central electrode material with high Ni content.

The above description should not be taken as limiting the invention to the embodiments, but rather, as will be apparent to those skilled in the art, numerous modifications and variations are possible without departing from the spirit of the invention.