A frit process for a frit assembly

Abstract

The application discloses a glass burning process of a glass burning assembly, wherein a glass insulator is installed in a shell through glass burning, and a pin contact is installed in the glass insulator through glass burning, and the pin contact is made of copper expansion alloy material, and the manufacturing steps are in sequence of pressing a glass blank, wax removal, glassing, assembling, sintering, mold unloading, first inspection, coating and second inspection. For the same specification of the pin contact, the copper expansion alloy pin contact has higher rated current, stronger current carrying capacity, lower contact resistance and lower temperature rise than the iron-nickel expansion alloy or Kovar alloy pin contact, and the product has more superior and reliable electrical performance; when the current and temperature rise of the glass burning assembly are constant, the diameter of the pin contact can be reduced by using the copper pin contact for glass burning, so that the overall shape of the product is reduced, and the miniaturization and light weight of the water-proof connector are realized; the iron-nickel expansion copper expansion alloy has no magnetism, and will not affect the equipment and instruments, and the magnetic interference problem is solved.

Description

Technical Field

[0001] The invention relates to a copper contact glass-sintered connector, in particular to a glass-sintering process for a glass-sintered component. Background Art

[0002] With the rapid development of the connector industry, demands for electrical performance, sealing reliability, magnetic interference resistance, and miniaturization of glass-fired connectors are increasing. According to GJB1216, the pins used in current glass-fired connectors are made of iron-nickel expansion alloy or Kovar alloy (Type B), which has inferior electrical performance compared to copper alloy (Type A). Electrical performance is primarily reflected in current carrying capacity, contact resistance, and temperature rise. When a product is subjected to a certain current, the lower the current carrying capacity, the higher the contact resistance, the higher the temperature rise, and the higher the heat generation. Excessive heat generation can easily soften certain heat-sensitive components and reduce the product's insulation resistance, significantly affecting product life and reliability. Furthermore, iron-nickel expansion alloy or Kovar alloy is magnetic, which can affect the proper operation of precision equipment.

[0003] The most important factor affecting the current-carrying capacity, contact resistance, temperature rise (heating), and magnetic interference of glass-fired products is the material of the pin contacts. The compatibility of the material expansion coefficients between parts (housing, pin contacts, glass mounting plate), and the compatibility of the glass-fired process and coating process affect the insulation resistance and appearance quality of the product under normal conditions.

[0004] The conventional and mature glass sintering process used in the connector industry is the "high-temperature sintering process." Products typically consist of pin contacts, a glass mounting plate, and a housing, sintered in a sintering furnace at temperatures between 900°C and 1100°C. At the highest temperature, the pin contacts and housing must remain molten, while the glass must melt. The molten glass, pin contacts, and housing are then integrated into a glass-sintered assembly. The glass-sintered assembly then undergoes a coating process, where the pin contacts are plated with gold, creating the finished glass-sintered product. The finished product must demonstrate reliable water pressure resistance and meet required insulation resistance and appearance quality.

[0005] Currently, connector pin contacts in the industry utilize conventional and proven materials such as pure copper, bronze, and brass, as well as iron-nickel expansion alloys and Kovar. Connector pin contacts that don't require glass sintering utilize pure copper or copper alloys such as bronze and brass, while connector pin contacts that require glass sintering utilize iron-nickel expansion alloys and Kovar. The reasons why connector pin contacts that require glass sintering use iron-nickel expansion alloys and Kovar rather than pure copper or copper alloys such as bronze and brass are unclear. The lack of glass sintering technology for copper pin contacts in the industry stems from the difficulties involved in selecting the appropriate material, glass powder, and the corresponding glass sintering and coating technologies.

[0006] Here are the reasons:

[0007] 1) Using a conventional, proven high-temperature sintering process, the sintering temperature is generally between 900°C and 1100°C. The melting temperature of pure copper is approximately 1083°C, while copper alloys such as bronze and brass melt between 700°C and 800°C. Iron-nickel expansion alloys or Kovar melt above 1400°C, stainless steel melts above 1300°C, and titanium alloys melt above 1600°C. Pin contacts made of pure copper or copper alloys will soften or even melt during high-temperature sintering, whereas iron-nickel expansion alloys or Kovar do not. Once softened, the pin contact material will deform, and its dimensions and shape will no longer meet the required specifications. Currently, mature materials suitable for high-temperature sintering processes include stainless steel, titanium alloy, iron-nickel expansion alloy, Kovar alloy and other high-temperature resistant materials. The shell material can be selected from stainless steel, titanium alloy, iron-nickel expansion alloy, Kovar alloy and other high-temperature resistant materials according to the application environment. However, the pin contacts need to transmit electrical signals (current or signal), which have certain requirements for the electrical conductivity and thermal conductivity of the material. Therefore, the pin contacts can only be made of iron-nickel expansion alloy and Kovar alloy.

[0008] 2) If pure copper or copper alloy materials are to be used as pin contacts for glass sintering and they do not soften, a low-temperature sintering process is required. The sintering temperature is generally between 400°C and 600°C. Pure copper or copper alloy materials will not melt, so a matching low-temperature encapsulation glass is required. Conventional low-temperature encapsulation glass after sintering is not resistant to subsequent coating processes. Part of the glass will dissolve in the coating solution in water or acid-base coating solution, and the quality cannot be controlled, which will lead to defects such as unreliable water pressure resistance and reduced insulation resistance. The quality and reliability of the sintered product are greatly reduced.

[0009] With the use of connectors, especially underwater connectors, the requirements for the electrical performance of the products are higher. The existing iron-nickel expansion alloy or Kovar alloy has strong magnetism, which will affect the normal operation of some high-precision equipment and instruments, thereby causing magnetic interference. In order to solve the electrical performance and magnetic interference problems of underwater connectors, the inventors have found a high-temperature resistant copper expansion alloy as the material for the pins after long-term research. However, the glass-fired components sintered by the existing glass-fired process do not meet the requirements for connector use in terms of sealing and electrical performance. After long-term research, the inventors found that the reasons for the failure of the glass-fired components to meet the standards are as follows: 1. The expansion coefficient of the contact material and the existing glass powder is different. 1. Mismatch, and the expansion coefficient does not match. In the final cooling stage of the sintering process, due to the mismatch in expansion coefficient, the shrinkage sizes of the two are inconsistent, and cracks will appear between the glass and metal, which will not only affect the sealing performance and cause water or air leakage, but also reduce the insulation resistance of the product or even make it unqualified; 2. The wax is not completely removed, and there are bubbles inside and on the surface of the sintered glass body, and the insulation performance of the product is unqualified; 3. The shape of the glass blank is greatly deformed and cannot be assembled; 4. Due to the special nature of its own organization, the high-temperature resistant copper expansion alloy material is not resistant to acid and alkali solutions. When the glass-fired component is coated, the pin substrate is directly immersed in the acid and alkali solution, which makes the pin surface particularly rough, and the roughness is much greater than the roughness requirement of the pin insertion part (Ra≤0.8). Summary of the Invention

[0010] The object of the present invention is to overcome the shortcomings of the prior art and provide a glass firing process for a glass firing component.

[0011] The object of the present invention is achieved by the following technical solution: a glass firing process for a glass firing assembly, wherein the glass firing assembly comprises a pin contact, a glass insulator and a shell, wherein the glass insulator is installed in the shell by glass firing, and the pin contact is installed in the glass insulator by glass firing, and the pin contact is made of a copper expansion alloy material with a material expansion coefficient of 8.0×10 -6 / K~10.0×10 -6 / K, the melting temperature is above 2000℃, and the expansion coefficient of the glass powder of the glass insulator is 5.0×10-6 / K~10.0×10 -6 / K, the expansion coefficient of the shell is 4.6×10 -6 / K~17.5×10 -6 / K, the glass firing process of the pin contact, glass insulator and shell includes the following steps:

[0012] S1: Pressing glass blanks: Put the selected glass powder into a blank pusher and press the glass powder according to the size and weight of the glass insulator to obtain a glass blank;

[0013] S2: Dewaxing: Use roving gloves to place the plate with the glass blanks on the mesh belt dewaxing vitrification furnace for dewaxing. The dewaxing step temperature ranges from room temperature to 550°C, and the dewaxing time is 14h to 48h.

[0014] S3: Vitrification: Place the waxed glass blank in a mesh belt vitrification furnace for vitrification. The vitrification step temperature ranges from room temperature to 730°C, and the total vitrification time is 12-16 hours.

[0015] S4: Assembling, fixing the vitrified glass blank with a graphite mold, and then assembling the pin contact parts, the housing and the glass blank together to form a component to be sintered;

[0016] S5: Sintering: placing the assembled components to be sintered in a sintering furnace at a sintering temperature of 940°C to 1100°C for a sintering time of 15 min to 60 min;

[0017] S6: demolding, disassembling the graphite mold to obtain a sintered component;

[0018] S7: The first inspection is to test the axial sealing performance and insulation resistance performance of the sintered component to ensure that the sintered component will not leak in the axial direction and the insulation resistance meets the requirements;

[0019] S8: Coating, using a rubber protective cover to protect the base material of the pin contact, then gold-plating the contact part of the pin contact, then shot blasting the oxide layer of the shell, and then pickling to remove the surface layer;

[0020] S9: Second inspection: the sealing performance and insulation resistance performance of the sintered component after coating are inspected again. After passing the inspection, the glass-sintered component is obtained.

[0021] In step S2, when draining wax, the mesh belt drain wax vitrification furnace is first heated to 240°C ~ 260°C, and the holding time is: 2.5h ~ 7h, and then heated to 300°C ~ 330°C, and the holding time is: 6.5h ~ 24h, and then heated to 380°C ~ 400°C, and the holding time is: 2h ~ 5h, and then heated to 420°C ~ 450°C, and the holding time is: 1h ~ 3h, and then heated to 480°C ~ 520°C, and the holding time is: 1h ~ 3h, and then heated to 530°C ~ 550°C, and the holding time is: 1h ~ 6h.

[0022] In step S3, the mesh belt vitrification furnace is first heated to 240°C ~ 260°C, with a holding time of 1.2h ~ 1.6h, and then heated to 300°C ~ 330°C, with a holding time of 3.6h ~ 4.8h, and then heated to 400°C ~ 470°C, with a holding time of 1.2h ~ 1.6h, and then heated to 500°C ~ 550°C, with a holding time of 1.2h ~ 1.6h, and then heated to 620°C ~ 650°C, with a holding time of 1.2h ~ 1.6h, and then heated to 690°C ~ 730°C, with a holding time of 2.4h ~ 3.2h.

[0023] The glass blank is vitrified four times. The glass blank must be turned over after each vitrification. The highest temperature of the step temperature for each vitrification is adjusted by ±3°C according to the shape of the glass out of the furnace. During each vitrification, the mesh belt vitrification furnace is first heated to 240°C~260°C with a holding time of 0.3h~0.4h, then heated to 300°C~330°C with a holding time of 0.9h~1.2h, then heated to 400°C~470°C with a holding time of 0.3h~0.4h, then heated to 500°C~550°C with a holding time of 0.3h~0.4h, then heated to 620°C~650°C with a holding time of 0.3h~0.4h, then heated to 690°C~730°C with a holding time of 0.6h~0.8h.

[0024] The present invention has the following advantages:

[0025] 1. The material of the glass-fired connector pin contact is copper expansion alloy, which has better electrical performance;

[0026] 2. For pin contacts of the same specification, copper expansion alloy pin contacts have higher rated current, stronger current carrying capacity, lower contact resistance, and lower temperature rise than iron-nickel expansion alloy or Kovar alloy pin contacts. This means lower heat generation (excessive heat generation can easily cause softening of certain heat-sensitive parts or wires, greatly reducing their lifespan). The product's electrical performance is superior and more reliable.

[0027] 3. When the current and temperature rise of glass-fired components are constant, the copper pin contacts are glass-fired to reduce the diameter of the pin contacts, thereby reducing the overall shape of the product and achieving miniaturization and lightweighting of the watertight connector.

[0028] 4. Solve the problem of magnetic interference. Iron-nickel expansion alloy or Kovar alloy has strong magnetism, which will affect the normal operation of some high-precision equipment and instruments, while copper expansion alloy is non-magnetic and will not affect the equipment and instruments. DETAILED DESCRIPTION

[0029] In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0030] Example 1: A glass firing process for a glass firing assembly, the glass firing assembly comprising a pin contact, a glass insulator, and a housing. The glass insulator is mounted in the housing by glass firing, and the pin contact is mounted in the glass insulator by glass firing. The pin contact is made of a copper expansion alloy material with a material expansion coefficient of 8.0×10 -6 / K~10.0×10 -6 / K, with a melting temperature of over 2000℃. This material is mainly used in aerospace engine nozzles, gas rudders, air rudders, electrical machining electrodes and other high-temperature resistant fields. It will not soften or melt at a sintering temperature of 900℃ to 1100℃ and can be sintered into shape. The electrical properties of the pin contacts made of copper expansion alloy are superior, with stronger current carrying capacity, smaller contact resistance, lower temperature rise and less heat generation. Since copper expansion alloy is non-magnetic, it will not affect equipment and instruments, thus completely solving the magnetic interference problem caused by iron-nickel expansion alloy glass-sintered connectors. The expansion coefficient of the glass powder of the glass insulator is 5.0×10 -6 / K~10.0×10 -6 / K, the expansion coefficient of the shell is 4.6×10 -6 / K~17.5×10 -6 / K, specifically, the glass firing process of the pin contact, glass insulator and shell includes the following steps:

[0031] S1: Pressing glass blanks: Put the selected glass powder into a blank pusher and press the glass powder according to the size and weight of the glass insulator to obtain a glass blank;

[0032] S2: wax removal, using roving gloves to place the plate with the glass blank on the mesh belt wax removal vitrification furnace for wax removal, the wax removal step temperature is room temperature ~ 550 ° C, and the wax removal time is 14 hours; specifically, when removing the wax, the mesh belt wax removal vitrification furnace is first heated to 240 ° C, the holding time is: 2.5 hours, then heated to 300 ° C, the holding time is: 6.5 hours, then heated to 380 ° C, the holding time is: 2 hours, then heated to 420 ° C, the holding time is: 1 hour, then heated to 480 ° C, the holding time is: 1 hour, then heated to 530 ° C, the holding time is: 1 hour, fully release or decompose the wax in the glass powder, so that it is completely removed, and there will be no bubbles inside and on the surface of the sintered glass body, thereby not affecting the insulation performance of the product;

[0033] S3: Vitrification. Place the waxed glass blank in a mesh belt vitrification furnace for vitrification. The vitrification step temperature ranges from room temperature to 730°C. The total vitrification time is 16 hours. Specifically, the mesh belt vitrification furnace is first heated to 260°C for 1.6 hours of heat preservation, then heated to 330°C for 4.8 hours of heat preservation, then heated to 470°C for 1.6 hours of heat preservation, then heated to 550°C for 1.6 hours of heat preservation, then heated to 650°C for 1.6 hours of heat preservation, then heated to 730°C for 3.2 hours of heat preservation. Since the glass blank is easily deformed due to softening during the vitrification process, and the gap between the glass mounting plate and the metal is small on both sides, once the deformation exceeds the reserved gap , then the parts cannot fit well during assembly, and the problem of assembly failure occurs. In order to control the deformation and not exceed the reserved gap, the glass blank is vitrified four times. The glass blank must be turned over after each vitrification. The highest temperature of the step temperature for each vitrification is adjusted by ±3℃ according to the shape of the glass out of the furnace. During each vitrification, the mesh belt vitrification furnace is first heated to 260℃ for 0.4h, then heated to 330℃ for 1.2h, then heated to 470℃ for 0.4h, then heated to 550℃ for 0.4h, then heated to 650℃ for 0.4h, then heated to 730℃ for 0.8h.

[0034] S4: Assembling, fixing the vitrified glass blank with a graphite mold, and then assembling the pin contact parts, the housing and the glass blank together to form a component to be sintered;

[0035] S5: Sintering: Place the assembled components to be sintered in a sintering furnace at a sintering temperature of 940°C for 60 minutes, so that the glass and metal are fully infiltrated and bonded, and the seal is firm. The produced glass-sintered components will not leak in the axial direction and the insulation resistance is qualified.

[0036] S6: demolding, disassembling the graphite mold to obtain a sintered component;

[0037] S7: The first inspection is to test the axial sealing performance and insulation resistance performance of the sintered component to ensure that the sintered component will not leak in the axial direction and the insulation resistance meets the requirements;

[0038] S8: Coating, use a rubber protective cover to protect the base material of the pin contact, then gold-plate the contact part of the pin contact, then use shot blasting to remove the oxide layer of the shell, and then pickle and remove the outer surface layer; the high-temperature resistant copper expansion alloy material is not resistant to acid and alkali solutions due to the particularity of its own organization. When the glass-sintered component is coated, the pin base material cannot be directly immersed in the acid and alkali solution. Therefore, a protective cover, replacement process and adjustment of the process sequence are used to solve the problem. Specifically, during the coating pretreatment, the pin base material is protected with a rubber protective cover, and then gold-plated first, and then other coating processes such as the shell are carried out. The oxide layer on the surface of the shell is sprayed off with a shot with greater pressure, and then the shell surface is removed by pickling. Through the new coating process, the copper expansion alloy pin contact base material is successively protected by a rubber protective cover and a gold-plated layer, which plays a protective role in acid and alkaline solutions. The surface of the pin contact will not become rough, and the roughness meets the requirements;

[0039] S9: The second inspection is to test the sealing performance and insulation resistance performance of the sintered components after coating. After passing the inspection, the glass-sintered components are obtained. The qualified glass-sintered components can be assembled with other components of the connector to form a connector that can be used underwater.

[0040] Example 2: A glass firing process for a glass firing assembly, the glass firing assembly comprising a pin contact, a glass insulator, and a housing. The glass insulator is mounted in the housing by glass firing, and the pin contact is mounted in the glass insulator by glass firing. The pin contact is made of a copper expansion alloy material with a material expansion coefficient of 8.0×10 -6 / K~10.0×10 -6 / K, with a melting temperature of over 2000℃. This material is mainly used in aerospace engine nozzles, gas rudders, air rudders, electrical machining electrodes and other high-temperature resistant fields. It will not soften or melt at a sintering temperature of 900℃ to 1100℃ and can be sintered into shape. The electrical properties of the pin contacts made of copper expansion alloy are superior, with stronger current carrying capacity, smaller contact resistance, lower temperature rise and less heat generation. Since copper expansion alloy is non-magnetic, it will not affect equipment and instruments, thus completely solving the magnetic interference problem caused by iron-nickel expansion alloy glass-sintered connectors. The expansion coefficient of the glass powder of the glass insulator is 5.0×10 -6 / K~10.0×10 -6 / K, the expansion coefficient of the shell is 4.6×10 -6 / K~17.5×10 -6 / K, specifically, the glass firing process of the pin contact, glass insulator and shell includes the following steps:

[0041] S1: Pressing glass blanks: Put the selected glass powder into a blank pusher and press the glass powder according to the size and weight of the glass insulator to obtain a glass blank;

[0042] S2: wax removal, using roving gloves to place the plate with the glass blank on the mesh belt wax removal vitrification furnace for wax removal, the wax removal step temperature is room temperature ~ 550 ° C, and the wax removal time is 48 hours; specifically, when removing the wax, the mesh belt wax removal vitrification furnace is first heated to 240 ° C ~ 260 ° C, the holding time is: 7 hours, then heated to 330 ° C, the holding time is: 24 hours, then heated to 400 ° C, the holding time is: 5 hours, then heated to 450 ° C, the holding time is: 3 hours, then heated to 520 ° C, the holding time is: 3 hours, then heated to 550 ° C, the holding time is: 6 hours, fully release or decompose the wax in the glass powder, so that it is completely removed, and there will be no bubbles inside and on the surface of the sintered glass body, thereby not affecting the insulation performance of the product;

[0043] S3: Vitrification. Place the waxed glass blank in a mesh belt vitrification furnace for vitrification. The vitrification step temperature is from room temperature to 730°C. The total vitrification time is 12 hours. Specifically, the mesh belt vitrification furnace is first heated to 240°C and the holding time is 1.2 hours. Then it is heated to 300°C and the holding time is 3.6 hours. Then it is heated to 400°C and the holding time is 1.2 hours. Then it is heated to 500°C and the holding time is 1.2 hours. Then it is heated to 620°C and the holding time is 1.2 hours. Then it is heated to 690°C and the holding time is 2.4 hours. Since the glass blank is easily deformed due to softening during the vitrification process, and the gap between the glass mounting plate and the metal is small, once the deformation exceeds the reserved gap, , then the parts cannot fit well during assembly, and the problem of assembly failure occurs. In order to control the deformation and not exceed the reserved gap, the glass blank is vitrified four times. The glass blank must be turned over after each vitrification. The highest temperature of the step temperature for each vitrification is adjusted by ±3℃ according to the shape of the glass out of the furnace. During each vitrification, the mesh belt vitrification furnace is first heated to 240℃ for 0.3h, then heated to 300℃ for 0.9h, then heated to 400℃ for 0.3h, then heated to 500℃ for 0.3h, then heated to 620℃ for 0.3h, then heated to 690℃ for 0.6h.

[0044] S4: Assembling, fixing the vitrified glass blank with a graphite mold, and then assembling the pin contact parts, the housing and the glass blank together to form a component to be sintered;

[0045] S5: Sintering: Place the assembled components to be sintered in a sintering furnace at a sintering temperature of 1100°C for 15 minutes, so that the glass and metal are fully infiltrated and bonded, and the seal is firm. The produced glass-sintered components will not leak in the axial direction and the insulation resistance is qualified.

[0046] S6: demolding, disassembling the graphite mold to obtain a sintered component;

[0047] S7: The first inspection is to test the axial sealing performance and insulation resistance performance of the sintered component to ensure that the sintered component will not leak in the axial direction and the insulation resistance meets the requirements;

[0048] S8: Coating, use a rubber protective cover to protect the base material of the pin contact, then gold-plate the contact part of the pin contact, then use shot blasting to remove the oxide layer of the shell, and then pickle and remove the outer surface layer; the high-temperature resistant copper expansion alloy material is not resistant to acid and alkali solutions due to the particularity of its own organization. When the glass-sintered component is coated, the pin base material cannot be directly immersed in the acid and alkali solution. Therefore, a protective cover, replacement process and adjustment of the process sequence are used to solve the problem. Specifically, during the coating pretreatment, the pin base material is protected with a rubber protective cover, and then gold-plated first, and then other coating processes such as the shell are carried out. The oxide layer on the surface of the shell is sprayed off with a shot with greater pressure, and then the shell surface is removed by pickling. Through the new coating process, the copper expansion alloy pin contact base material is successively protected by a rubber protective cover and a gold-plated layer, which plays a protective role in acid and alkaline solutions. The surface of the pin contact will not become rough, and the roughness meets the requirements;

[0049] S9: The second inspection is to test the sealing performance and insulation resistance performance of the sintered components after coating. After passing the inspection, the glass-sintered components are obtained. The qualified glass-sintered components can be assembled with other components of the connector to form a connector that can be used underwater.

[0050] Example 3:

[0051] A glass firing process for a glass firing component, wherein the glass firing component comprises a pin contact, a glass insulator and a shell. The glass insulator is installed in the shell by glass firing, and the pin contact is installed in the glass insulator by glass firing. The pin contact is made of a copper expansion alloy material with a material expansion coefficient of 8.0×10 -6 / K~10.0×10 -6 / K, with a melting temperature of over 2000℃. This material is mainly used in aerospace engine nozzles, gas rudders, air rudders, electrical machining electrodes and other high-temperature resistant fields. It will not soften or melt at a sintering temperature of 900℃ to 1100℃ and can be sintered into shape. The electrical properties of the pin contacts made of copper expansion alloy are superior, with stronger current carrying capacity, smaller contact resistance, lower temperature rise and less heat generation. Since copper expansion alloy is non-magnetic, it will not affect equipment and instruments, thus completely solving the magnetic interference problem caused by iron-nickel expansion alloy glass-sintered connectors. The expansion coefficient of the glass powder of the glass insulator is 5.0×10 -6 / K~10.0×10 -6 / K, the expansion coefficient of the shell is 4.6×10 -6 / K~17.5×10 -6 / K, specifically, the glass firing process of the pin contact, glass insulator and shell includes the following steps:

[0052] S1: Pressing glass blanks: Put the selected glass powder into a blank pusher and press the glass powder according to the size and weight of the glass insulator to obtain a glass blank;

[0053] S2: wax removal, using roving gloves to place the plate with the glass blank on the mesh belt wax removal vitrification furnace for wax removal, the wax removal step temperature is room temperature ~ 550 ° C, and the wax removal time is 31 hours; specifically, when removing the wax, the mesh belt wax removal vitrification furnace is first heated to 250 ° C, the holding time is: 4.5 hours, then heated to 315 ° C, the holding time is: 15.5 hours, then heated to 390 ° C, the holding time is: 3.5 hours, then heated to 435 ° C, the holding time is: 2 hours, then heated to 500 ° C, the holding time is: 2 hours, then heated to 540 ° C, the holding time is: 3.5 hours, fully release or decompose the wax in the glass powder, so that it is completely removed, and there will be no bubbles inside and on the surface of the sintered glass body, thereby not affecting the insulation performance of the product;

[0054] S3: Vitrification. Place the waxed glass blank in a mesh belt vitrification furnace for vitrification. The vitrification step temperature ranges from room temperature to 730°C. The total vitrification time is 14 hours. Specifically, the mesh belt vitrification furnace is first heated to 250°C for 1.4 hours of heat preservation, then heated to 315°C for 4.2 hours of heat preservation, then heated to 435°C for 1.4 hours of heat preservation, then heated to 525°C for 1.4 hours of heat preservation, then heated to 635°C for 1.4 hours of heat preservation, then heated to 710°C for 2.8 hours of heat preservation. Since the glass blank is easily deformed due to softening during the vitrification process, and the gap between the glass mounting plate and the metal is small on both sides, once the deformation exceeds the reserved gap, the glass blank will be deformed during the vitrification process. During assembly, the parts cannot fit well together, and the problem of assembly failure occurs. In order to control the deformation and not exceed the reserved gap, the glass blank is vitrified four times. The glass blank must be turned over after each vitrification. The highest temperature of the step temperature for each vitrification is adjusted by ±3°C according to the shape of the glass out of the furnace. During each vitrification, the mesh belt vitrification furnace is first heated to 240°C~260°C, and the holding time is 0.35h. Then it is heated to 315°C, and the holding time is 1.05h. Then it is heated to 435°C, and the holding time is 0.35h. Then it is heated to 525°C, and the holding time is 0.35h. Then it is heated to 635°C, and the holding time is 0.35h. Then it is heated to 710°C, and the holding time is 0.7h.

[0055] S4: Assembling, fixing the vitrified glass blank with a graphite mold, and then assembling the pin contact parts, the housing and the glass blank together to form a component to be sintered;

[0056] S5: Sintering: Place the assembled components to be sintered in a sintering furnace at a sintering temperature of 1020°C for 37 minutes, so that the glass and metal are fully infiltrated and bonded, and the seal is firm. The produced glass-sintered components will not leak in the axial direction and the insulation resistance is qualified.

[0057] S6: demolding, disassembling the graphite mold to obtain a sintered component;

[0058] S7: The first inspection is to test the axial sealing performance and insulation resistance performance of the sintered component to ensure that the sintered component will not leak in the axial direction and the insulation resistance meets the requirements;

[0059] S8: Coating, use a rubber protective cover to protect the base material of the pin contact, then gold-plate the contact part of the pin contact, then use shot blasting to remove the oxide layer of the shell, and then pickle and remove the outer surface layer; the high-temperature resistant copper expansion alloy material is not resistant to acid and alkali solutions due to the particularity of its own organization. When the glass-sintered component is coated, the pin base material cannot be directly immersed in the acid and alkali solution. Therefore, a protective cover, replacement process and adjustment of the process sequence are used to solve the problem. Specifically, during the coating pretreatment, the pin base material is protected with a rubber protective cover, and then gold-plated first, and then other coating processes such as the shell are carried out. The oxide layer on the surface of the shell is sprayed off with a shot with greater pressure, and then the shell surface is removed by pickling. Through the new coating process, the copper expansion alloy pin contact base material is successively protected by a rubber protective cover and a gold-plated layer, which plays a protective role in acid and alkaline solutions. The surface of the pin contact will not become rough, and the roughness meets the requirements;

[0060] S9: The second inspection is to test the sealing performance and insulation resistance performance of the sintered components after coating. After passing the inspection, the glass-sintered components are obtained. The qualified glass-sintered components can be assembled with other components of the connector to form a connector that can be used underwater.

[0061] A glass-sintered assembly made from one of the three aforementioned embodiments was tested for performance and compared with existing iron-nickel expansion alloys or Kovar alloys. The pin contact diameters were chosen to be φ4.5 mm, φ3 mm, and φ1.5 mm, respectively. The performance comparison table is as follows:

[0062]

[0063]

[0064]

[0065] From Tables 1 to 4 above, we can see that:

[0066] 1. The material of the glass-fired connector pin contact is copper expansion alloy, which has better electrical performance;

[0067] 2. For pin contacts of the same specification, copper expansion alloy pin contacts have higher rated current, stronger current carrying capacity, lower contact resistance, and lower temperature rise than iron-nickel expansion alloy or Kovar alloy pin contacts. This means lower heat generation (excessive heat generation can easily cause softening of certain heat-sensitive parts or wires, greatly reducing their lifespan). The product's electrical performance is superior and more reliable.

[0068] 3. When the current and temperature rise of glass-fired components are constant, the copper pin contacts are glass-fired to reduce the diameter of the pin contacts, thereby reducing the overall shape of the product and achieving miniaturization and lightweighting of the watertight connector.

[0069] 4. Solve the problem of magnetic interference. Iron-nickel expansion alloy or Kovar alloy has strong magnetism, which will affect the normal operation of some high-precision equipment and instruments, while copper expansion alloy is non-magnetic and will not affect the equipment and instruments.

[0070] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A glass firing process for a glass fired component, characterized in that: The glass-fired assembly includes a pin contact, a glass insulator, and a shell. The glass insulator is installed in the shell through glass firing, and the pin contact is installed in the glass insulator through glass firing. The pin contact is made of copper expansion alloy material with a material expansion coefficient of 8.0×10 -6 / K~10.0×10 -6 / K, the melting temperature is above 2000°C, and the expansion coefficient of the glass powder of the glass insulator is 5.0×10 -6 / K~10.0×10 -6 / K, the expansion coefficient of the shell is 4.6×10 -6 / K~17.5×10 -6 / K, the glass firing process of the pin contact, glass insulator and shell includes the following steps: S1: Pressing glass blanks: Put the selected glass powder into a blank pusher and press the glass powder according to the size and weight of the glass insulator to obtain a glass blank; S2: Dewaxing: Use roving gloves to place the plate with the glass blanks on the mesh belt dewaxing vitrification furnace for dewaxing. The dewaxing step temperature ranges from room temperature to 550°C, and the dewaxing time is 14h to 48h. S3: Vitrification: Place the waxed glass blank in a mesh belt vitrification furnace for vitrification. The vitrification step temperature ranges from room temperature to 730°C, and the total vitrification time is 12-16 hours. S4: Assembling, fixing the vitrified glass blank with a graphite mold, and then assembling the pin contact parts, the housing and the glass blank together to form a component to be sintered; S5: Sintering: placing the assembled components to be sintered in a sintering furnace at a sintering temperature of 940°C to 1100°C for a sintering time of 15 min to 60 min; S6: demolding, disassembling the graphite mold to obtain a sintered component; S7: The first inspection is to test the axial sealing performance and insulation resistance performance of the sintered component to ensure that the sintered component will not leak in the axial direction and the insulation resistance meets the requirements; S8: Coating, using a rubber protective cover to protect the base material of the pin contact, then gold-plating the contact part of the pin contact, then shot blasting the oxide layer of the shell, and then pickling to remove the surface layer; S9: Second inspection: the sealing performance and insulation resistance performance of the sintered component after coating are inspected again. After passing the inspection, the glass-sintered component is obtained.

2. The glass firing process of a glass firing component according to claim 1, characterized in that: In the step S2, when the wax is discharged, the mesh belt wax discharge vitrification furnace is first heated to 240°C to 260°C for a holding time of 2.5h to 7h, then heated to 300°C to 330°C for a holding time of 6.5h to 24h, then heated to 380°C to 400°C for a holding time of 2h to 5h, then heated to 420°C to 450°C for a holding time of 1h to 3h, then heated to 480°C to 520°C for a holding time of 1h to 3h, then heated to 530°C to 550°C for a holding time of 1h to 6h.

3. The glass firing process of a glass firing component according to claim 1, characterized in that: In step S3, the mesh belt vitrification furnace is first heated to 240°C to 260°C for a holding time of 1.2h to 1.6h, then heated to 300°C to 330°C for a holding time of 3.6h to 4.8h, then heated to 400°C to 470°C for a holding time of 1.2h to 1.6h, then heated to 500°C to 550°C for a holding time of 1.2h to 1.6h, then heated to 620°C to 650°C for a holding time of 1.2h to 1.6h, then heated to 690°C to 730°C for a holding time of 2.4h to 3.2h.

4. The glass firing process of a glass firing component according to claim 1, characterized in that: The glass blank is vitrified four times, and the glass blank must be turned over after each vitrification. The highest temperature of the step temperature for each vitrification is adjusted by ±3°C according to the shape of the glass out of the furnace. During each vitrification, the mesh belt vitrification furnace is first heated to 240°C~260°C with a holding time of 0.3h~0.4h, then heated to 300°C~330°C with a holding time of 0.9h~1.2h, then heated to 400°C~470°C with a holding time of 0.3h~0.4h, then heated to 500°C~550°C with a holding time of 0.3h~0.4h, then heated to 620°C~650°C with a holding time of 0.3h~0.4h, then heated to 690°C~730°C with a holding time of 0.6h~0.8h.

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