Plasma mass spectrometer sampling cone with active cooling function and preparation method thereof

Abstract

The invention discloses a plasma mass spectrometer sampling cone with an active cooling function, which comprises a sealing surface, a cone body is arranged on the sealing surface, a cone opening with a porous structure is metallurgically bonded at the upper part of the cone body, and a plurality of cooling medium flow channels communicated with the porous structure of the cone opening are arranged in the cone body. The invention also discloses a preparation method of the sampling cone with the active cooling function for the plasma mass spectrometer. The preparation method comprises the following steps: 1, processing a blank; 2, conical opening forming; 3, heat treatment; and 4, shape processing. The sampling cone comprises the sealing surface, the cone body, the cone opening and the cooling medium flow channel, heat of the sampling cone is taken away to cool the sampling cone by means of active cooling and porous sweating cooling, and a layer of continuous and uniformly-distributed protective gas film is formed in the cone opening area, with the highest temperature and the most serious thermal scouring, of the sampling cone; volatile matters and high temperature are isolated from the protected wall surface of the sampling cone, so that efficient protection on the sampling cone is realized.

Description

Technical Field

[0001] This invention belongs to the technical field of sampling cones for plasma mass spectrometers, specifically relating to a sampling cone for plasma mass spectrometers with active cooling function and its preparation method. Background Technology

[0002] Inductively coupled plasma mass spectrometry (ICP-MS) boasts advantages such as high sensitivity, low inter-element interference, good precision, and ease of operation. In recent years, it has been widely used both domestically and internationally in trace element detection in industries such as environmental geology and non-ferrous metals. Its function is to extract ions from the sample to be analyzed from plasma; that is, after the sample is ionized, the sampling cone captures these ions and transports them to the intercepting cone.

[0003] The existing sampling cone is formed by fixing a cone body to a base. The cone body is essentially a conical cylinder with different taper on its outer and inner surfaces (i.e., the wall thickness gradually decreases from bottom to top). The front section has a conical hole with a diameter of 0.8–2 mm, and its surface is nearly mirror-like. However, during long-term operation, the cone temperature continuously rises. Metal oxides and carbides generated by high-temperature ionization accumulate on the sampling cone surface, constantly eroding and corroding the front end of the conical hole, leading to deformation and dimensional changes in the hole, severely affecting the equipment's detection performance. Furthermore, the continuous rise and fluctuation of the cone temperature during long-term operation exacerbates the evaporation of the sample, resulting in significant signal fluctuations in the sample detection and thus uncontrollable changes in the detection results.

[0004] To address the aforementioned issues, existing solutions typically include the following aspects: 1) Periodic cleaning of the sampling cone, i.e., removing deposits from the cone orifice and body using physical or chemical methods to restore the cone's size and surface condition. However, this method requires disassembling and reassembling the instrument, which is time-consuming and laborious, and does not solve the problem of detection signal fluctuations caused by cone temperature changes. 2) Improving the cone material, i.e., using new erosion-resistant, corrosion-resistant, and high-strength materials to reduce changes in the cone's shape and surface condition caused by long-term use. This method increases the cost of the cone and also does not solve the problem of detection signal fluctuations caused by cone temperature changes. 3) Installing heat dissipation columns and cooling pipes on the outside of the cone to reduce or control the cone temperature. This method solves the cone temperature fluctuation to some extent, but the structure is complex, disassembly is difficult, and the external cooling water volume control needs to be matched with the ionization process to ensure that the sampling cone temperature remains balanced.

[0005] Therefore, there is a need to provide a sampling cone for a plasma mass spectrometer with active cooling function and its preparation method. Summary of the Invention

[0006] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a sampling cone for a plasma mass spectrometer with active cooling function. This sampling cone consists of a sealing surface, a cone body, a cone opening, and a cooling medium flow channel. Without changing the original external dimensions of the sampling cone, it achieves overall cooling and cone opening protection through active cooling and a flowing gas film generated by porous sweating phase change. This ensures that the equipment is not subjected to high-temperature impacts from plasma or erosion by ionization products during long-term operation.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a sampling cone for a plasma mass spectrometer with active cooling function, characterized in that the sampling cone includes a sealing surface, a cone body is provided on the sealing surface, the upper part of the cone body is metallurgically bonded with a cone opening with a porous structure, the cone body is provided with multiple cooling medium channels communicating with the porous structure of the cone opening, the porosity of the porous structure is 10%~15%, and the average pore diameter is 3μm~8μm.

[0008] The above-mentioned sampling cone for a plasma mass spectrometer with active cooling function is characterized in that multiple cooling medium channels are distributed at equal angles, the number of channels is 4 to 7, the diameter is 0.2 mm to 1 mm, and the internal surface roughness Ra ≤ 1.2 μm. The sealing surface is provided with a transmission ring that communicates with all cooling medium channels, and the transmission ring is connected to an input channel.

[0009] The sampling cone for a plasma mass spectrometer with active cooling function described above is characterized in that the height of the cone opening is 3mm to 5mm.

[0010] The above-mentioned sampling cone for a plasma mass spectrometer with active cooling function is characterized in that the cone body is made of nickel, nickel alloy, platinum or platinum alloy, and the cone opening and sealing surface are made of the same material as the cone body.

[0011] In addition, the present invention also provides a method for preparing a sampling cone for a plasma mass spectrometer with active cooling function, characterized in that the method includes the following steps: Step 1, Blank Processing: A cone with multiple cooling medium flow channels and a sealing surface with a transmission ring and an input channel are prepared by machining to obtain a preliminary blank; Step 2, Conical forming: The preliminary blank prepared in Step 1 is placed in the metal cavity. Then, metal powder of the same material as the preliminary blank is melted point by point and layer by layer with a high-energy beam according to the three-dimensional model of the porous structure of the cone. The melting scan is performed to prepare a cone with a porous structure on the upper part of the cone of the preliminary blank, thus obtaining the sampling cone blank. Step 3: Heat treatment: The sampling cone blank obtained in Step 2 is subjected to heat treatment; Step 4: External shaping: The sampling cone blank after heat treatment in step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function.

[0012] This invention employs low-cost, traditional machining to achieve low-cost, high-efficiency processing of a cone with multiple cooling medium channels and a sealing surface with a transmission ring and input channel. Subsequently, melting scanning metallurgical forming is used, utilizing a high-energy beam to partially melt metal powder to create three-dimensional interconnected pores, which serve as functional channels within the cone opening—a porous structure. This method is simple and efficient, achieving a metallurgical bond between the porous functional region and the dense structural region. It is highly suitable for small-sized, complex components that combine structure and function. Heat treatment further ensures the strength of the metallurgical bond between the dense cone and the porous cone opening. Finally, surface finishing completes the fabrication of a sampling cone for a plasma mass spectrometer with active cooling. The process is simple, low-cost, and easy to promote and use.

[0013] The above method is characterized in that the average particle size of the metal powder in step two is 10μm~40μm and the sphericity is greater than 98%. By controlling the particle size and sphericity of the metal powder, the present invention ensures high stability and high reliability during preparation, ensures the strength of the cone mouth, and facilitates the metallurgical bonding of the cone mouth and the cone body.

[0014] The above method is characterized in that, in step two, the high-energy beam is a laser beam or an electron beam, and the beam spot diameter of the high-energy beam is no greater than 80 μm; when the high-energy beam is a laser beam, the melting scan is performed under an argon atmosphere; when the high-energy beam is an electron beam, the melting scan is performed under a vacuum degree greater than 1 × 10⁻⁶. -2 The process is carried out under Pa conditions. This invention ensures density and surface finish during the cone forming process by controlling the beam spot diameter. If the beam spot is too large, the energy is dispersed, making it difficult to obtain high-density parts. At the same time, the inner and outer surfaces of the parts are rough, the flow resistance inside the flow channel increases, and the cooling effect is weakened. If the beam spot size is too small, the hardware equipment cannot achieve it, which will also reduce production efficiency. By controlling the atmosphere characteristics during forming, the structural stability and reliability of the cone are ensured.

[0015] The above method is characterized in that, in step two, a layer of metal powder with a thickness of 20μm to 35μm is uniformly laid in each melting scan, and the power density of the high-energy beam is (0.03~0.04)×T. m ×ρ J / mm 3 , among which, T m ρ is the melting point of the metal powder, expressed in °C; ρ is the density of the metal powder, expressed in g / cm³. 3This invention provides a solid guarantee for the obtained porous structure by controlling the thickness of the metal powder layer during deposition. It prevents the inability to obtain the required pore size and porosity when the thickness is too large, and also prevents the inability of existing equipment and metal powders to achieve the layer-by-layer deposition process requirements when the thickness is too small. By controlling the power density of the high-energy beam, this invention ensures sufficient surface diffusion and fusion between metal powders without complete melting, ensuring that the aforementioned characteristic porous structure can be obtained at this power density. It prevents excessive energy density from causing volume diffusion of the metal powder, which would reduce its porosity and pore size to levels that do not meet design requirements. It also prevents the conical nozzle prepared with insufficient energy density from having excessively large porosity and pore size, and whose mechanical strength fails to meet usage requirements.

[0016] The method described above is characterized in that the heat treatment temperature in step three is (0.5~0.6) × T. m The heat treatment time is 2h~3h, where T m The value is the melting point of the metal powder, expressed in °C. This invention further ensures the metallurgical bond strength between the cone and the cone opening through post-forming heat treatment, and controls the heat treatment temperature to further enhance the bond strength between the cone and the cone opening, ensuring the safety and reliability of the sampling cone during long-term service and preventing significant changes in the pore parameters of the porous structure of the cone opening.

[0017] The above method is characterized in that, in step four, the surface processing ensures that the surface roughness Ra of the sampling cone for the plasma mass spectrometer with active cooling function is ≤0.6μm, and that the external dimensions meet the usage requirements of the sampling cone. This invention controls the surface roughness and external dimensions of the surface-processed blank to meet the usage requirements of the sampling cone.

[0018] Compared with the prior art, the present invention has the following advantages: 1. This invention is based on an in-depth study and analysis of the working principle of existing plasma mass spectrometers and the failure mechanism of their sampling cones. By utilizing active cooling and porous sweating cooling, the cooling medium flows from the cooling medium channel to the porous structure at the cone opening under high pressure, carrying away the heat of the cone and cooling it down. At the same time, the cooling medium flowing to the cone opening overflows from the porous structure, forming a continuous and uniformly distributed protective gas film in the cone opening area where the sampling cone temperature is the highest and thermal erosion is the most severe. This film isolates volatiles and high temperatures from the protected sampling cone wall, thereby achieving efficient protection of the sampling cone.

[0019] 2. Based on a large amount of experimental data, this invention has determined the optimal internal structure of the sampling cone. Its cooling medium flow channel and the cone opening with a porous structure achieve efficient and precise temperature control of the sampling cone during equipment operation without changing the existing external dimensions and assembly form of the sampling cone. Furthermore, the fluid generated by the vaporization of the cooling medium provides efficient protection for the cone opening, effectively reducing sampling cone failure caused by deformation or size changes of the cone opening at the front end of the cone. This significantly extends the service life of the sampling cone and reduces the frequency of equipment maintenance and parts replacement.

[0020] 3. The preparation of this invention adopts a combination of powder metallurgy near-net-shape forming and traditional processing technology. First, the cone with multiple cooling medium flow channels and the sealing surface with a transmission ring and input channel are processed by low-cost machining. Then, high-energy beam deposition is used layer by layer. Through reasonable control of process parameters, the metal powder is not completely melted and pores are formed by volume accumulation, which serve as three-dimensional interconnected channels for sweating and cooling. The method is simple to operate, cost controllable, widely applicable, and has a high yield. It is especially suitable for the technical upgrading and transformation of existing large-scale production lines. It can significantly improve the added value of products without changing the existing core equipment.

[0021] 4. This invention combines near-net-shape powder metallurgy with traditional processing techniques. The preparation process is simple and does not change the assembly form of the existing sampling cone. Its service life far exceeds that of the existing structure, and it has broad application prospects in equipment such as inductively coupled plasma mass spectrometers.

[0022] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the sampling cone for a plasma mass spectrometer with active cooling function according to the present invention.

[0024] Figure 2 This is a cross-sectional view of the connection between the cone opening and the cone body of the sampling cone for the plasma mass spectrometer with active cooling function according to the present invention.

[0025] Figure 3 This is a partial cross-sectional view of the cooling medium flow channel of the sampling cone for the plasma mass spectrometer with active cooling function of the present invention.

[0026] Figure 4 This is a schematic diagram of the sampling cone for the plasma mass spectrometer with active cooling function of the present invention when there are 4 cooling medium channels.

[0027] Figure 5Temperature change curves during actual operation of the sampling cone for plasma mass spectrometer with active cooling function prepared in Example 2 of the present invention and the traditional sampling cone.

[0028] Explanation of reference numerals in the attached figures: Detailed Implementation

[0029] The sampling cone for a plasma mass spectrometer with active cooling function of the present invention is described in detail through Example 1.

[0030] Example 1 like Figures 1-4 As shown, the sampling cone for the plasma mass spectrometer with active cooling function in this embodiment includes a sealing surface 1, a cone 2 is provided on the sealing surface 1, and a cone mouth 3 with a porous structure is metallurgically bonded to the upper part of the cone 2. Multiple cooling medium channels 4 are provided inside the cone 2 and communicate with the porous structure of the cone mouth 3. The porosity of the porous structure is 10%~15% and the average pore diameter is 3μm~8μm.

[0031] It should be noted that the external dimensions and assembly structure of the sampling cone in this embodiment are completely consistent with those of the existing sampling cone. It mainly includes: a sealing surface 1, a cone 2, a cooling medium channel 4, and a cone opening 3 with a porous structure. The sealing surface 1 is used for assembly with the main body of the equipment. The cone 2 is used to form a support for the front cone opening 3. The cooling medium channel 4 is used to uniformly deliver the medium into the cone opening 3 with a porous structure, while controlling the wall temperature of the cone 2 within a suitable range. The cone opening 3 with a porous structure is located at the front end of the cone 2. Through the three-dimensional interconnected pores inside, the cooling medium undergoes a phase change from liquid to gas under high temperature conditions, absorbing the heat at the front end of the cone opening 3. At the same time, the continuously flowing gas film forms a continuous and stable protection for the cone opening 3.

[0032] It should be noted that, after in-depth research and analysis of the working principle of existing plasma mass spectrometers and the failure mechanism of the sampling cones used, this embodiment utilizes active cooling and porous sweating cooling. The cooling medium overflows from the porous structure under high pressure, carrying away the heat of the sampling cone and cooling it down. At the same time, a continuous and uniformly distributed protective gas film is formed in the cone opening 3 region where the sampling cone temperature is the highest and the thermal erosion is the most severe, isolating the volatiles and high temperature from the protected sampling cone wall, thereby achieving efficient protection of the sampling cone.

[0033] It should be noted that in this embodiment, the sealing surface 1 and the cone body 2 of the sampling cone are integrally formed, and their external structure is completely consistent with that of a conventional cone body 2, which will not cause inconvenience to the operator. The cone body 2 and the cone opening 3 with a porous structure are metallurgically bonded, ensuring the strength and stability of the entire structure under complex working conditions and long-term service. The cone opening 3 with a porous structure is connected to the cooling medium flow channel 4 inside the cone body 2, see... Figure 2 When the cooling medium enters the cone 2 from the outside during operation, a phase change from liquid to gas occurs on the three-dimensional interconnected pore surface of the cone opening 3. On the one hand, it absorbs the heat energy of the cone 2 and cone opening 3 regions, and on the other hand, it protects the cone opening 3 from the scouring and corrosion of ionization products through the gas film, thereby achieving active cooling and active protection of the cone opening 3 region.

[0034] It should be noted that the porosity of the porous structure enables precise control of the flow rate and cooling effect of the cooling medium. This prevents the required cooling medium flow rate from being too large when the porosity of the cone 3 region exceeds 15%, which would lead to insufficient energy consumption and increased demand for cooling medium. It also prevents the flow resistance of the cooling medium in the porous cone 3 from increasing exponentially and decreasing its permeability when the porosity of the cone 3 region is less than 15%. In such cases, the flow could easily stop and overheat at the front end of the cone 3 during long-term operation of the equipment, which would quickly lead to the failure of the cone 2.

[0035] It should be noted that the flow rate of the cooling medium in the cone 3 region is controlled by controlling the average pore size of the porous structure. This is because the average pore size is inversely proportional to the flow rate in the three-dimensional pores of the liquid. This prevents the flow rate from being too slow when the average pore size exceeds 8μm, which could easily lead to flow interruption and overheating at the front end of the cone 3, thus causing the cone 2 to fail. It also prevents the problem that when the average pore size is less than 3μm, although the flow rate can be guaranteed, the existing mature preparation process cannot meet the requirement of an open porosity of 10%~15%, which would cause additional increases in processing difficulty and production cost.

[0036] It should be noted that, as Figure 3 As shown, the cooling medium channel 4 is located in the middle of the cone 2, which ensures the cooling effect of the cooling medium on the cone 2 itself and the structural strength of the cone 2.

[0037] In this embodiment, the multiple cooling medium channels 4 are distributed at equal angles, with a number of 4 to 7 channels, a diameter of 0.2 mm to 1 mm, and an internal surface roughness Ra ≤ 1.2 μm. The sealing surface 1 is provided with a transmission ring 5 that communicates with all the cooling medium channels 4, and the transmission ring 5 is connected to an input channel 6. By controlling the number and surface quality of the cooling medium channels 4 inside the cone 2, the cooling rate of the cooling medium on the cone 2 and the phase change process of the cooling medium from liquid to gas at the cone opening 3 are controlled, achieving the optimal cooling effect. This prevents the insufficiency of insufficient cooling medium channels 4, which would make it difficult to cool the entire area of ​​the cone 2 and to uniformly and effectively deliver the cooling medium to the porous structure of the cone opening 3. It also prevents the overall strength and rigidity of the cone 2 from being significantly weakened due to more than 7 cooling medium channels 4, which would fail to meet the usage requirements, and also prevents the cooling medium's thermal conductivity from far exceeding the maximum temperature that the sampling cone can reach, resulting in wasted cooling capacity and significantly increasing the processing difficulty of the sampling cone. By controlling the surface roughness of the cooling medium channels 4, the heat exchange efficiency between the cooling medium and the cone 2 is maximized, ensuring that the cooling medium flow rate is minimized while achieving cooling of the cone 2 and efficient and controllable delivery process. It also allows the cooling medium to be heated to a certain temperature inside the cone 2, promoting phase change and heat absorption on the surface of the porous cone opening 3, thus better protecting the leading edge of the cone opening 3.

[0038] It should be noted that, as Figure 1 As shown, the wall thickness of cone 2 gradually decreases from sealing surface 1 to cone opening 3. Therefore, the diameter of cooling medium flow channel 4 also gradually decreases as the wall thickness decreases. Overall, the diameter at the bottom is the largest at 1 mm, and then gradually decreases to 0.2 mm at the top, ensuring the best cooling effect and structural strength of the flow channel.

[0039] In this embodiment, the height of the conical opening 3 is 3mm~5mm. By controlling the height of the conical opening 3, see... Figure 2 That is Figure 2 The height of h is 3mm~5mm because during the operation of the equipment, the temperature in the 3mm~5mm area at the front edge of the cone 2 is 300℃ higher than that of the entire sampling cone. This area is the area with the most severe high-temperature erosion corrosion. Therefore, setting this area as the cone opening 3 with a porous structure has the best protection effect. On the other hand, a reasonable height of the cone opening 3 with a porous structure can reduce the processing difficulty and reduce the processing cost.

[0040] In this embodiment, the cone 2 is made of nickel, a nickel alloy, platinum, or a platinum alloy, and the cone opening 3 and the sealing surface 1 are made of the same material as the cone 2. This invention controls the material of the sampling cone to make it suitable for various working conditions.

[0041] Figure 4This is a schematic diagram of the sampling cone for the plasma mass spectrometer with active cooling function of the present invention when there are 4 cooling medium channels. Figure 4 As can be seen, the cooling medium flow channel 4 is evenly distributed along the axial direction of the cone 2, ensuring that the cooling medium cools the wall of the cone 2 and delivers sufficient cooling medium to the cone opening 3 with a porous structure.

[0042] The preparation method of a sampling cone for a plasma mass spectrometer with active cooling function according to the present invention is described in detail through Examples 2 to 5.

[0043] Example 2 This embodiment includes the following steps: Step 1, Blank Processing: Using Inconel 718 nickel alloy, a cone with 6 cooling medium flow channels and a sealing surface with a transfer ring and input channel are prepared to obtain a preliminary blank with a cone height of 19.2 mm; Step 2, Conical Forming: The preliminary blank prepared in Step 1 is placed in a metal cavity under an argon atmosphere. Then, using metal powder of the same material as the preliminary blank, with an average particle size of 28 μm and a sphericity of 99%, a laser beam with a beam diameter of 50 μm is used to melt the metal powder point by point and layer by layer according to the three-dimensional model of the porous structure of the conical opening, with a layer thickness of 20 μm, at a power density of 320 J / mm². 3 Melting scanning was performed to prepare a porous cone-shaped opening with a height of 3.2 mm on the upper part of the cone of the preliminary blank, thus obtaining the sampling cone blank; Step 3, heat treatment: The sampling cone blank obtained in step 2 is heat treated at 750℃ for 3 hours; Step 4: External shaping: The sampling cone blank after heat treatment in Step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function, which has a surface roughness Ra=0.5μm and external dimensions that meet the usage requirements of the sampling cone.

[0044] Testing revealed that the porous structure of the sampling cone with active cooling function prepared in this embodiment has a porosity of 12.3% and an average pore diameter of 4.5 μm. Six cooling medium channels are evenly distributed within the cone wall, with an included angle of 60° between them. The surface roughness inside the cooling medium channels is 1.0 μm, and the external dimensions meet the equipment assembly requirements.

[0045] The plasma mass spectrometer with active cooling function prepared in this embodiment was installed in the equipment for batch detection and evaluation using a sampling cone. To more accurately test the temperature change at the tip of the sampling cone, a temperature measuring device was used to monitor the temperature change at the tip of the sampling cone. Figure 5As shown, traditional sampling cones, lacking cooling protection, maintain a temperature close to room temperature during standby. However, once the sample enters the device and begins to ionize, the sampling cone temperature rapidly rises, exceeding 570°C. This temperature fluctuation during ionization causes significant stress on the cone material. In contrast, the plasma mass spectrometer sampling cone with active cooling prepared in this embodiment maintains a surface temperature below 90°C throughout the test, fully validating the cooling effect of this invention and completely eliminating the thermal shock experienced by the sampling cone. Testing shows that the lifespan of the plasma mass spectrometer sampling cone with active cooling prepared in this embodiment is more than five times that of traditional sampling cones.

[0046] Example 3 This embodiment includes the following steps: Step 1, billet processing: The nickel is machined to prepare a cone with 4 cooling medium flow channels and a sealing surface with a transfer ring and an input channel, resulting in a preliminary billet with a cone height of 25.5 mm; Step 2, Conical Forming: The preliminary blank prepared in Step 1 is placed in a metal cavity under an argon atmosphere. Then, using metal powder of the same material as the preliminary blank, with an average particle size of 37 μm and a sphericity of 98.6%, a laser beam with a beam diameter of 45 μm is used to melt the metal powder point by point and layer by layer according to the three-dimensional model of the porous structure of the conical opening, with a layer thickness of 25 μm. The power density is 514 J / mm². 3 Melting scanning was performed to prepare a porous cone-shaped opening with a height of 3.8 mm on the upper part of the cone of the preliminary blank, thus obtaining the sampling cone blank; Step 3, heat treatment: The sampling cone blank obtained in step 2 is heat treated at 867℃ for 2 hours; Step 4: External shaping: The sampling cone blank after heat treatment in Step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function, which has a surface roughness Ra=0.4μm and external dimensions that meet the usage requirements of the sampling cone.

[0047] Testing revealed that the porosity of the porous structure at the cone opening of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is 14.1%, the average pore diameter is 5.7 μm, four cooling medium channels are evenly distributed within the cone wall with an included angle of 90°, the surface roughness inside the cooling medium channels is 0.8 μm, and the external dimensions meet the equipment assembly requirements. Tests showed that the lifespan of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is more than four times that of traditional sampling cones.

[0048] Example 4 This embodiment includes the following steps: Step 1, Blank Processing: Using machining platinum, a cone with 7 cooling medium flow channels and a sealing surface with a transfer ring and an input channel are prepared to obtain a preliminary blank with a cone height of 18.5 mm; Step 2, Conical forming: Place the preliminary blank prepared in Step 1 under a vacuum of 1×10⁻⁶. -3 Within the metal cavity of Pa, metal powder of the same material as the initial billet, with an average particle size of 40 μm and a sphericity of 99.2%, is then melted point-by-point and layer-by-layer using an electron beam with a beam diameter of 50 μm, following a three-dimensional model of a porous structure with a conical aperture, and at a layer thickness of 35 μm. The power density is 1140 J / mm². 3 Melting scanning was performed to prepare a porous cone-shaped opening with a height of 3.1 mm on the upper part of the cone of the preliminary blank, thus obtaining the sampling cone blank; Step 3, Heat treatment: The sampling cone blank obtained in Step 2 is heat treated at 886℃ for 2.5 hours; Step 4: External shaping: The sampling cone blank after heat treatment in Step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function, which has a surface roughness Ra=0.6μm and external dimensions that meet the usage requirements of the sampling cone.

[0049] Testing revealed that the porosity of the porous structure at the cone opening of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is 14.8%, the average pore diameter is 7.7 μm, seven cooling medium channels are evenly distributed within the cone wall at equal angles, the surface roughness inside the cooling medium channels is 0.6 μm, and the external dimensions meet the equipment assembly requirements. Tests showed that the lifespan of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is more than four times that of traditional sampling cones.

[0050] Example 5 This embodiment includes the following steps: Step 1, billet processing: Using machining of PtRh10 alloy, a cone with 5 cooling medium flow channels and a sealing surface with a transmission ring and an input channel are prepared to obtain a preliminary billet with a cone height of 23.3 mm; Step 2, Conical forming: Place the preliminary blank prepared in Step 1 under a vacuum of 1×10⁻⁶. -3 Within the metal cavity of Pa, metal powder of the same material as the initial billet, with an average particle size of 10 μm and a sphericity of 99.0%, is then melted point-by-point and layer-by-layer using an electron beam with a beam diameter of 30 μm, following a three-dimensional model of a porous structure with a conical aperture, and layer by layer with a thickness of 30 μm. The power density is 1298 J / mm². 3Melting scanning was performed to prepare a porous cone-shaped opening with a height of 4.8 mm on the upper part of the cone of the preliminary blank, thus obtaining the sampling cone blank; Step 3, Heat treatment: The sampling cone blank obtained in Step 2 is heat treated at 1018℃ for 2 hours; Step 4: External shaping: The sampling cone blank after heat treatment in Step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function, which has a surface roughness Ra=0.5μm and external dimensions that meet the usage requirements of the sampling cone.

[0051] Testing revealed that the porosity of the porous structure at the cone opening of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is 10.2%, the average pore diameter is 3.2 μm, seven cooling medium channels are evenly distributed within the cone wall at equal angles, the surface roughness inside the cooling medium channels is 0.6 μm, and the external dimensions meet the equipment assembly requirements. Tests showed that the lifespan of the plasma mass spectrometer sampling cone with active cooling function prepared in this embodiment is more than four times that of traditional sampling cones.

[0052] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the inventive essence shall still fall within the protection scope of the present invention.

Claims

1. A sampling cone for a plasma mass spectrometer with active cooling function, characterized in that, The sampling cone includes a sealing surface (1), on which a cone (2) is provided. The upper part of the cone (2) is metallurgically bonded with a cone opening (3) with a porous structure. The cone (2) is provided with multiple cooling medium channels (4) that are connected to the porous structure of the cone opening (3). The porosity of the porous structure is 10%~15%, and the average pore diameter is 3μm~8μm.

2. A sampling cone for a plasma mass spectrometer with active cooling function according to claim 1, characterized in that, The cooling medium channels (4) are distributed at equal angles, with a number of 4 to 7 channels, a diameter of 0.2 mm to 1 mm, and an internal surface roughness Ra ≤ 1.2 μm. The sealing surface (1) is provided with a transmission ring (5) that communicates with all the cooling medium channels (4), and the transmission ring (5) is connected to an input channel (6).

3. A sampling cone for a plasma mass spectrometer with active cooling function according to claim 1, characterized in that, The height of the cone (3) is 3mm~5mm.

4. A sampling cone for a plasma mass spectrometer with active cooling function according to claim 1, characterized in that, The cone (2) is made of nickel, nickel alloy, platinum or platinum alloy, and the cone opening (3) and sealing surface (1) are made of the same material as the cone (2).

5. A method for preparing a sampling cone for a plasma mass spectrometer with active cooling function as described in any one of claims 1 to 4, characterized in that, The method includes the following steps: Step 1, billet processing: A cone (2) with multiple cooling medium flow channels (4) and a sealing surface (1) with a transmission ring (5) and an input channel (6) are prepared by machining to obtain a preliminary billet; Step 2, Conical opening (3) forming: The preliminary blank prepared in step 1 is placed in the metal cavity. Then, metal powder of the same material as the preliminary blank is melted point by point and layer by layer with a high-energy beam according to the three-dimensional model of the porous structure of the conical opening (3). The melting scan is performed to prepare a conical opening (3) with a porous structure on the upper part of the cone (2) of the preliminary blank, and the sampling cone blank is obtained. Step 3: Heat treatment: The sampling cone blank obtained in Step 2 is subjected to heat treatment; Step 4: External shaping: The sampling cone blank after heat treatment in step 3 is surface-machined to obtain a sampling cone for plasma mass spectrometer with active cooling function.

6. The method according to claim 5, characterized in that, The metal powder mentioned in step two has an average particle size of 10μm to 40μm and a sphericity greater than 98%.

7. The method according to claim 5, characterized in that, The high-energy beam mentioned in step two is either a laser beam or an electron beam, and the beam spot diameter of the high-energy beam is no greater than 80 μm; when the high-energy beam is a laser beam, the melting scan is performed under an argon atmosphere; when the high-energy beam is an electron beam, the melting scan is performed under a vacuum degree greater than 1 × 10⁻⁶. -2 The experiment was conducted under the condition of Pa.

8. The method according to claim 5, characterized in that, In step two, during each melting scan, a layer of metal powder with a thickness of 20μm~35μm is uniformly deposited, and the power density of the high-energy beam is (0.03~0.04)×T. m ×ρ J / mm 3 , among which, T m ρ is the melting point of the metal powder, expressed in °C; ρ is the density of the metal powder, expressed in g / cm³. 3 .

9. The method according to claim 5, characterized in that, The heat treatment temperature mentioned in step three is (0.5~0.6) × T m The heat treatment time is 2h~3h, where T m is the melting point of the metal powder, expressed in °C.

10. The method according to claim 5, characterized in that, In step four, the surface processing ensures that the surface roughness Ra of the sampling cone for the plasma mass spectrometer with active cooling function is ≤0.6μm, and that the external dimensions meet the usage requirements of the sampling cone.

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