A mounting structure and brazing method for large hard alloy and steel

Abstract

The present invention relates to the field of welding technology, and in particular, to a mounting structure and brazing method for a cemented carbide block and steel. The present invention solves the problem of poor quality of the weld between the cemented carbide and the steel substrate. In order to solve the above problem, an embodiment of the present invention proposes a solution to the continuous compressive stress on the side of the cemented carbide block during the brazing process and provides a mounting structure, including: a base; a fixed support, the fixed support is arranged on the base, and the fixed support can slide along the base; a stopper, the stopper is connected to the fixed support, a first mounting position is formed between the stopper and the base, a steel substrate is arranged in the first mounting position, the steel substrate is provided with a second mounting position, and the cemented carbide block is placed in the second mounting position; wherein the stopper contacts the steel substrate on one side away from the fixed support and contacts the cemented carbide block on one end away from the base, there are two fixed supports, the two fixed supports are located on opposite sides of the base, and each fixed support is provided with at least one stopper.

Description

Technical Field

[0001] The invention relates to the technical field of welding, and in particular to an installation structure of a large block of hard alloy and steel and a brazing method. Background Art

[0002] Cemented carbide is often used in the manufacture of engineering machinery tools due to its high wear resistance and high strength. Its existing application scenarios are mainly to braze cemented carbide with steel substrates. Cemented carbide plays its high hardness and high wear resistance, and steel substrate plays its high toughness and impact resistance. Brazing is currently the mainstream method of connecting the two in this field. At present, manual brazing at room temperature is mainly used for brazing operations. The main work content is to place the cemented carbide and the steel substrate in the correct position, place sheet brazing material between the cemented carbide and the steel substrate, and use induction heating equipment to induction heat the workpiece. After reaching the brazing temperature, the brazing material begins to melt, flow, and overflow. However, during the operation, the cemented carbide block will be slightly offset due to the effect of the magnetic field, and the linear expansion coefficient of the cemented carbide block and the steel substrate is inconsistent during the cooling process, which is easy to form a gap on the joint surface. Workers need to adjust the position of the cemented carbide block in time and make a lot of repairs at the weld to form a good brazing joint. Due to the limited manpower of the operator, it is impossible to support many pieces of cemented carbide at the same time, and the quality of the weld is difficult to guarantee. Summary of the invention

[0003] The problem solved by the invention is that during the welding process between the cemented carbide and the steel substrate, continuous compressive stress cannot be applied to the cemented carbide laterally, resulting in poor weld quality.

[0004] To solve the above problems, an embodiment of the present invention provides a mounting structure, including: a base; a fixed support, the fixed support is arranged on the base, and the fixed support can slide along the base; a stopper, the stopper is connected to the fixed support, a first mounting position is formed between the stopper and the base, a steel base is arranged in the first mounting position, the steel base is provided with a second mounting position, and the carbide block is placed in the second mounting position; wherein the stopper is in contact with the steel base on one side away from the fixed support and in contact with the carbide block on one end away from the base, there are two fixed supports, the two fixed supports are located on opposite sides of the base, and each fixed support is provided with at least one stopper.

[0005] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the setting of the fixed support being movable relative to the base allows the installation structure to be brazed for steel substrates of different sizes; the setting of the stopper allows the cemented carbide block to be subjected to lateral stress during the brazing process, thereby ensuring that the weld between the cemented carbide block and the steel substrate can maintain a more appropriate width, reducing the impact of differences in linear expansion coefficients of different materials; the setting of multiple stoppers allows multiple cemented carbide blocks to be welded at one time, thereby increasing the efficiency of brazing and the practicality of the installation structure.

[0006] In one embodiment of the present invention, the stop portion includes: a first connecting section, the first connecting section is connected to the fixed support, and the first connecting section can move relative to the fixed support; an adjusting device, the adjusting device is connected to the first connecting section; and a stop member, the stop member is connected to the adjusting device and is arranged on the side of the adjusting device away from the base.

[0007] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the stopper can provide pressure to the side of the carbide block during the brazing process, the setting of the first connecting section allows the horizontal position of the stopper to be adjusted, the adjusting device allows the vertical height of the stopper to be adjusted, and the setting of the first connecting section and the adjusting device allows the position of the stopper to be adapted to the carbide block, making the overall structure of the installation structure simpler.

[0008] In one embodiment of the present invention, the first connecting section includes: a first connecting rod, the first connecting rod and the fixed support, at least a portion of the first connecting rod enters the interior of the fixed support; a transfer rod, the transfer rod is connected to the first connecting rod, the transfer rod is bent toward the direction of the adjusting device, and the adjusting device is connected to the transfer rod.

[0009] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the setting of the first connecting rod allows the stop part to move relative to the fixed bracket, and also makes the connection between the stop part and the fixed bracket more secure; the transfer rod allows the adjustment device to be located above the fixed bracket, and also makes the overall structure of the stop part more stable.

[0010] In one embodiment of the present invention, the adjusting device includes: an adjusting screw connected to the transfer rod; a transition rod connected to the stopper; wherein the adjusting screw adjusts the distance between the transition rod and the base by rotating.

[0011] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the setting of the adjusting screw makes the height adjustment of the stopper more convenient, and the setting of the transition rod makes the connection between the adjusting screw and the stopper more stable.

[0012] In one embodiment of the present invention, the stopper further comprises: a spring, one end of the spring is connected to the transfer rod, and the other end of the spring is connected to the fixed support.

[0013] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: by arranging a spring between the fixed support and the transfer rod, the action force given by the carbide block is converted into a reaction force applied to the carbide block, so that the carbide block is subjected to greater stress and the relative position of the carbide block and the steel substrate remains unchanged.

[0014] In one embodiment of the present invention, a brazing method is also provided, which includes: pre-assembling a steel substrate and a cemented carbide block to obtain a pre-assembled workpiece; placing the pre-assembled workpiece in a brazing device for brazing to obtain a welded workpiece; placing the welded workpiece in an insulation box and slowly cooling it to room temperature, and processing the surface of the welded workpiece to obtain a finished workpiece.

[0015] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: pre-assembling workpieces makes the brazing process of the steel substrate and the cemented carbide block more convenient, improves the work efficiency of brazing, ensures that the molten brazing material is blocked by the obstruction and will not flow out during brazing, and ensures the brazing quality of the weld. Workers only need to perform pre-assembly before welding, and no high-temperature brazing operation is required, which improves the working environment of workers.

[0016] In one embodiment of the present invention, a steel substrate and a cemented carbide block are preassembled to obtain a preassembled workpiece, including: placing the steel substrate in a first installation position and placing the cemented carbide block in a second installation position; adjusting the stopper so that the stopper contacts the cemented carbide block; adding solder and a flow barrier to the weld between the steel substrate and the cemented carbide block to obtain a first mixture; and allowing the first mixture to stand for 20 to 40 minutes to obtain a preassembled product.

[0017] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by pre-setting the solder at the top, the solder on the top can replenish the amount of solder during the brazing process, which is beneficial to ensure that the volume of the molten solder is larger than the volume of the weld, and by setting the obstruction, the molten solder is blocked by the obstruction, which reduces the loss of solder and also improves the quality of the weld.

[0018] In one embodiment of the present invention, the preassembled workpiece is placed in a brazing device for brazing to obtain a welded workpiece, including: placing the preassembled workpiece in a sealed space, adjusting the heating position of a heating device according to the position of the preassembled workpiece; starting a vacuum pump to adjust the relative vacuum degree of the sealed space to 10 -3 Pa; start the heating device to raise the temperature in the sealed space to 700°C, perform vacuum brazing, and obtain a welded workpiece.

[0019] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: by adjusting the position of the heating coil, the heating of each part of the pre-assembled workpiece is more evenly distributed; the vacuum environment can reduce the degree of oxidation of the pre-assembled workpiece during brazing and improve the brazing quality.

[0020] In one embodiment of the present invention, a brazing filler metal and a flow barrier are added to the weld between a steel substrate and a cemented carbide block to obtain a first mixture, including: applying a paste brazing agent on the surface of the brazing filler metal to obtain a wet brazing filler metal; stirring water and gypsum powder into a paste to form a flow barrier; applying the flow barrier to the outside of the weld, and placing the wet brazing filler metal into the weld between the steel substrate and the cemented carbide block.

[0021] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: when the wet solder forms a molten state and flows at high temperature, gypsum can prevent the wet solder from flowing to the outside of the weld, ensuring that the solder will not be lost and the quality of brazing is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the installation structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the connection between the stopper and the fixed support of the present invention;

[0024] Figure 3 It is a schematic diagram of the specific structure of the stopper of the present invention;

[0025] Figure 4 This is a schematic diagram of the second installation position of the present invention;

[0026] Figure 5 The figure is a flow chart of the brazing method of the present invention.

[0027] Description of reference numerals:

[0028] 110-base; 111-first movable groove; 120-fixed support; 121-second movable groove; 130-steel matrix; 140-hard alloy block; 150-first mounting position; 160-second mounting position; 200-stopper; 210-first connecting rod; 220-transfer rod; 230-adjusting device; 231-adjusting screw; 232-transition rod; 240-stopper; 241-ceramic shaft; 242-ceramic sleeve. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] [First embodiment]

[0031] See also Figures 1 to 4In a specific embodiment, the mounting structure includes: a base 110; a fixed support 120, the fixed support 120 is arranged on the base 110, and the fixed support 120 can slide along the base 110; a stopper 200, the stopper 200 is connected to the fixed support 120, a first mounting position 150 is formed between the stopper 200 and the base 110, a steel substrate 130 is arranged in the first mounting position 150, the steel substrate 130 is provided with a second mounting position 160, and a cemented carbide block 140 is placed in the second mounting position 160; wherein, the stopper 200 contacts the steel substrate 130 on one side away from the fixed support 120 and contacts the cemented carbide block 140 on one end away from the base 110, there are two fixed supports 120, the two fixed supports 120 are located on opposite sides of the base 110, and each fixed support 120 is provided with at least one stopper 200.

[0032] The base 110 is a rectangular parallelepiped, and the side with the largest area of ​​the rectangular parallelepiped is the mounting surface. Two first movable grooves 111 are provided along the long side of the mounting surface. The cross-section of the first movable groove 111 is in the shape of a "convex" character. The fixed bracket is arranged parallel to the short side. The fixed bracket is provided with a connecting hole. The fixing piece is placed in the first movable groove 111 and passes through the connecting hole upward to fix the fixed bracket. A second movable groove 121 is provided on the side of the fixed bracket close to the first mounting position 150. One end of the stopper 200 is located inside the second movable groove 121, and the other end contacts the cemented carbide block 140. Multiple stoppers 200 can be placed in the second movable groove 121, and multiple cemented carbide blocks 140 can be placed on the second mounting position 160. Each cemented carbide block 140 contacts a stopper 200 respectively to prevent the cemented carbide block 140 from moving toward the fixed bracket during welding, thereby ensuring smooth brazing.

[0033] During the brazing process, the carbide block 140 and the steel substrate 130 are in an environment above 700°C, and both the carbide block 140 and the steel substrate 130 will expand in volume, and the linear expansion coefficient of the steel substrate 130 is almost more than 3 times that of the carbide block 140. Therefore, it is necessary to apply stress to the carbide block 140 from the side to ensure that the relative position between the carbide block 140 and the steel substrate 130 does not change. When the carbide block 140 expands, it will contact the stopper 200, one end of the stopper 200 is connected to the fixed support 120, and the fixed support 120 is fixed to the base 110, ensuring the stability of the connection of one end of the stopper 200.

[0034] Preferably, the position of the fixed bracket can be adjusted according to the size of the steel base 130. When the steel base 130 is larger, the fixed bracket can be moved away from the first installation position 150. When the steel base 130 is smaller, the fixed bracket can be moved closer to the first installation position 150.

[0035] Preferably, the number of the stoppers 200 can be adjusted according to the number of cemented carbide blocks 140 to achieve simultaneous brazing of multiple cemented carbide blocks 140, thereby improving work efficiency.

[0036] In the related art, a clamping fixture is used for fastening. Currently, the representative of such fixtures on the market is a G-type clamp, which is mostly made of carbon steel and has a linear expansion coefficient similar to that of the steel substrate 130. Therefore, if a G-type clamp is used for fixing, the G-type clamp will loosen and lose the fastening effect due to the inconsistent linear expansion coefficient during brazing. There is also a method of manually tightening with a push rod to eliminate the gap between the cemented carbide block 140 and the steel substrate 130. Due to the limited manpower of the operator, many cemented carbide blocks 140 cannot be supported at the same time, and the efficiency cannot be improved without ensuring the work quality.

[0037] The setting that the fixed support 120 can move relative to the base 110 allows the installation structure to be brazed for steel substrates 130 of different sizes. The setting of the stopper 200 allows the cemented carbide block 140 to be subjected to lateral stress during the brazing process, ensuring that the weld between the cemented carbide block 140 and the steel substrate 130 can maintain a more appropriate width, reducing the impact of the difference in linear expansion coefficients of different materials. The setting of multiple stoppers 200 allows multiple cemented carbide blocks 140 to be welded in one brazing operation, thereby increasing the efficiency of brazing and the practicality of the installation structure.

[0038] [Second embodiment]

[0039] In a specific embodiment, the stop portion 200 includes: a first connecting section, the first connecting section is connected to the fixed support 120, and the first connecting section can move relative to the fixed support 120; an adjusting device 230, the adjusting device 230 is connected to the first connecting section; a stop member 240, the stop member 240 is connected to the adjusting device 230, and is arranged on the side of the adjusting device 230 away from the base 110.

[0040] See also Figure 2 One end of the first connecting section is embedded in the second movable groove 121 and can move with respect to the second movable groove 121. The other end of the first connecting section is bent and arranged upwardly perpendicular to the base 110. One end of the adjusting device 230 is connected to the bent section of the first connecting section, and the other end is connected to the stopper 240. The adjusting device 230 can adjust the distance of the stopper 240 relative to the base 110.

[0041] After the fixed support 120 is fixed, the height of the stopper 240 is first adjusted by the adjusting device 230 to make the height of the stopper 240 consistent with the height of the cemented carbide block 140, ensuring that the center of the cemented carbide block 140 is at the same height as the center of the stopper 240. When the cemented carbide block 140 to be welded is small, the top of the stopper 240 is made to be consistent in height with the top of the cemented carbide block 140, and then the first connecting section is moved along the second movable section to make the stopper 240 at the center of the cemented carbide block 140 in the horizontal direction. After the position adjustment is completed, the first connecting section and the adjusting device 230 are fixed, and the base 110 is placed in the brazing equipment for brazing.

[0042] The stopper 240 can provide pressure to the side of the carbide block 140 during the brazing process. The setting of the first connecting section allows the horizontal position of the stopper 240 to be adjusted, and the adjusting device 230 allows the vertical height of the stopper 240 to be adjusted. The setting of the first connecting section and the adjusting device 230 allows the position of the stopper 240 to be adapted to the carbide block 140, making the overall structure of the installation structure simpler.

[0043] [Third embodiment]

[0044] In a specific embodiment, the first connecting section includes: a first connecting rod 210, the first connecting rod 210 and the fixed support 120, at least a portion of the first connecting rod 210 enters the interior of the fixed support 120; a transfer rod 220, the transfer rod 220 is connected to the first connecting rod 210, the transfer rod 220 is bent toward the direction of the adjustment device 230, and the adjustment device 230 is connected to the transfer rod 220.

[0045] See also Figure 3 A T-shaped block is provided at one end of the first connecting rod 210 entering the fixed support 120, and the T-shaped block can slide in the second movable groove 121. The transfer rod 220 is L-shaped, and one end of the transfer rod 220 is connected to the T-shaped block through a pin. The transfer rod 220 can rotate around the pin, and the other end is connected to the adjustment device 230.

[0046] During installation, place the T-shaped block into the second movable groove 121 from the side and observe the position of the stopper 240. When the stopper 240 is located at the center of the carbide block 140, fix the first connecting rod 210 to complete the fixation of the horizontal position of the stopper 240.

[0047] The setting of the first connecting rod 210 allows the stop part 200 to move relative to the fixed bracket, and also makes the connection between the stop part 200 and the fixed bracket more secure. The transfer rod 220 allows the adjustment device 230 to be located above the fixed bracket, and also makes the overall structure of the stop part 200 more stable.

[0048] [Fourth embodiment]

[0049] In a specific embodiment, the adjusting device 230 includes: an adjusting screw 231, the adjusting screw 231 is connected to the transfer rod 220; a transition rod 232, the transition rod 232 is connected to the stopper 240; wherein the adjusting screw 231 adjusts the distance between the transition rod 232 and the base 110 by rotating.

[0050] The adjusting screw 231 is connected to the adapter rod 220 and is used to adjust the height of the ceramic shaft 241 sleeve to match the height of the cemented carbide block 140. The transition rod 232 has a threaded hole at one end and a blind hole at the other end, and the stopper 240 is inserted into the blind hole of the transition rod 232.

[0051] The stopper 240 is composed of a ceramic shaft 241 and a ceramic sleeve 242, which are detachably connected to facilitate replacement of ceramic sleeves 242 of different thicknesses to suit different working environments. At the same time, the high temperature resistance and non-magnetic properties of ceramics are utilized to enable it to work at high temperatures without being inductively heated, thereby ensuring the stability of the side pressure supply.

[0052] The setting of the adjusting screw 231 makes the height adjustment of the stopper 240 more convenient, and the setting of the transition rod 232 makes the connection between the adjusting screw 231 and the stopper 240 more stable.

[0053] [Fifth embodiment]

[0054] In a specific embodiment, the stopper 200 further includes: a spring, one end of the spring is connected to the transfer rod 220 , and the other end of the spring is connected to the fixed support 120 .

[0055] One end of the spring is installed in the annular spring mounting groove on the transfer rod 220, and the other end is pressed against the side of the fixed support 120. During the brazing process, the carbide block 140 expands and contacts the ceramic sleeve 242, and gives the transfer rod 220 a force toward the fixed support 120. At this time, the spring is compressed and gives the transfer rod 220 a reaction force, which is transmitted to the ceramic shaft 241 sleeve and finally acts on the carbide block 140.

[0056] By setting a spring between the fixed support 120 and the adapter rod 220, the action force given by the cemented carbide block 140 is converted into a reaction force applied to the cemented carbide block 140, so that the stress on the cemented carbide block 140 is greater and the relative position of the cemented carbide block 140 and the steel substrate 130 remains unchanged.

[0057] [Sixth embodiment]

[0058] See also Figure 5 In a specific embodiment, a brazing method is also provided, the brazing method comprising:

[0059] S100, pre-assembling the steel substrate and the cemented carbide block to obtain a pre-assembled workpiece;

[0060] S200, placing the preassembled workpiece into a brazing device for brazing to obtain a welded workpiece;

[0061] S300, placing the welding workpiece into a heat preservation box to slowly cool to room temperature, and treating the surface of the welding workpiece to obtain a finished workpiece.

[0062] Furthermore, in step S100, the steel substrate is placed on the first mounting position, and the cemented carbide block is placed on the second mounting position, and brazing material and flow barriers are added between the welds. When a preassembled workpiece is brazed, the new steel substrate and the cemented carbide block can be preassembled synchronously. After the brazing of the current preassembled workpiece is completed, the next one can be immediately placed in the brazing equipment, thereby increasing the efficiency of the brazing work.

[0063] Furthermore, in step S200, the preassembled workpiece is placed in a brazing device and the temperature is raised to above 700°C. During the brazing process, the brazing material is melted by the heat and enters the weld to form a good weld. The flow barrier can prevent the loss of the brazing material, further increasing the utilization rate of the material.

[0064] Furthermore, in step S300, the welding workpiece after high-temperature treatment is taken out from the brazing equipment and then placed in an insulation chamber to allow the temperature of the welding workpiece to drop slowly to avoid the influence of too fast temperature drop on the weld. After cooling to room temperature, the surface of the welding workpiece is polished and sandblasted to make the surface clean and tidy.

[0065] Pre-assembling workpieces makes the brazing process between the steel substrate and the cemented carbide block more convenient, improves the brazing efficiency, ensures that the molten brazing material is blocked by the obstruction and will not flow out during brazing, and ensures the brazing quality of the weld. Workers only need to perform pre-assembly before welding, avoiding brazing operations at high temperatures and improving the working environment of workers.

[0066] [Seventh embodiment]

[0067] In a specific embodiment, the steel substrate and the cemented carbide block are preassembled to obtain a preassembled workpiece, comprising:

[0068] S110, placing the steel substrate in a first installation position, and placing the cemented carbide block in a second installation position;

[0069] S120, adjusting the stopper so that the stopper contacts the cemented carbide block;

[0070] S130, adding a brazing filler metal and a flow barrier to the weld between the steel substrate and the cemented carbide block to obtain a first mixture;

[0071] S140, allowing the first mixture to stand for 20 to 40 minutes to obtain a preassembled product.

[0072] Furthermore, in step S120, the position of the fixed bracket is adjusted according to the size of the steel substrate, and the height of the stopper is adjusted according to the position of the cemented carbide block to ensure that the stopper can contact the cemented carbide block and is located at the center of the side of the cemented carbide block.

[0073] Furthermore, in step S130, brazing filler metal is prefabricated at the top weld of the steel substrate. During the brazing process, the volume of the molten brazing filler metal is ensured to be greater than the volume of the weld, thereby ensuring the weld penetration rate and avoiding incomplete welding of the upper end due to insufficient brazing filler metal. This improves the quality of the brazed joint. Flow blockers are applied to the welds except the top. After drying, the flow blockers will be adsorbed on the surface of the steel substrate, thereby ensuring that the molten brazing filler metal is blocked by the flow blockers and will not be lost during brazing, thereby reducing the waste of brazing filler metal while also ensuring the quality of the weld.

[0074] Furthermore, in step S140, the first mixture is allowed to stand at room temperature for 20 to 40 minutes, usually for 30 minutes, until the surface of the baffle is solidified and the pre-assembly is completed.

[0075] By presetting the solder at the top, the amount of solder can be replenished at the top during the brazing process, which helps to ensure that the volume of the molten solder is larger than the volume of the weld. By setting up obstructions, the molten solder is blocked by the obstructions, which reduces the loss of solder and improves the quality of the weld.

[0076] [Eighth embodiment]

[0077] In a specific embodiment, the preassembled workpiece is placed in a brazing device for brazing to obtain a welded workpiece, including:

[0078] S210, placing the preassembled workpiece into a sealed space, and adjusting the heating position of the heating device according to the position of the preassembled workpiece;

[0079] S220, start the vacuum pump to adjust the relative vacuum degree of the sealed space to 10 -3 Pa;

[0080] S230, start the heating device, raise the temperature in the sealed space to 700°C, perform vacuum brazing, and obtain a welded workpiece.

[0081] Furthermore, in step S210, after the preassembled workpiece is placed in the brazing equipment, the heating device is adjusted according to the size of the preassembled workpiece and the number of carbide blocks placed. Usually, the heating is driven by an induction power supply, and the inside of the brazing equipment is heated by electromagnetic induction. When adjusting the position, the position of the coil is moved to a position that matches the preassembled workpiece to ensure that all positions of the preassembled workpiece are heated evenly during the heating process.

[0082] Further, in step S220, after the pre-assembled workpiece is placed in the brazing equipment, the hatch of the brazing equipment is closed to form a sealed space inside the brazing equipment, and then the vacuum pump is started to draw the relative vacuum degree of the brazing environment where the pre-assembled workpiece is located to 10 -3 Pa or less, thereby reducing the oxygen content in the brazing environment of the workpiece, reducing the degree of oxidation of the workpiece during brazing, and improving the brazing quality of the brazed joint.

[0083] Furthermore, in step S230, when the brazing environment is met, the sealed space is heated. During the vacuum brazing process, the brazing material melts due to the heat and fills the weld. The molten brazing material cannot flow out due to the barrier and remains in the weld, thereby further improving the strength of the weld.

[0084] [Ninth embodiment]

[0085] In a specific embodiment, a brazing filler metal and a flow barrier are added to the weld between the steel substrate and the cemented carbide block to obtain a first mixture, comprising:

[0086] S131, applying a paste soldering agent on the solder surface to obtain a wet solder;

[0087] S132, mixing water and gypsum powder into a paste to form a flow barrier;

[0088] S133. Apply the flow barrier to the outside of the weld and place the wetted brazing material into the weld between the steel substrate and the cemented carbide block.

[0089] Furthermore, in step S131, during the pre-assembly process, paste solder is evenly applied on the surface of the solder to obtain a wet solder, which helps to wetting the solder and the steel substrate and the cemented carbide block during brazing and remove metal oxides. Subsequently, the wet solder is placed between the steel substrate and the cemented carbide block. During the brazing process, the wet solder is heated to a molten state and fills the weld, thereby completing the welding of the cemented carbide block and the steel substrate.

[0090] Further, in step S132, the gypsum powder is stirred into a paste with water, when the thickness of the gypsum is between 3 mm and 6 mm.

[0091] Furthermore, in step S133, the prepared gypsum is evenly applied to the weld between the cemented carbide block and the steel substrate. After standing for 30 minutes, the gypsum will dry and adsorb to the surface of the steel substrate. At this time, the workpiece is pre-assembled. In the subsequent brazing process, when the wetted brazing material forms a molten state and flows under high temperature, the gypsum can prevent the wetted brazing material from flowing to the outside of the weld, ensuring that the brazing material will not be lost, thereby ensuring the quality of brazing.

[0092] Preferably, the raw material of the flow blocker can also be putty powder, which can be mixed with water into a paste and applied to the outside of the weld to block the flow of solder.

[0093] [Tenth embodiment]

[0094] In a specific embodiment, the preassembled workpiece is placed in a brazing device, and the relative vacuum is drawn to 10 -3 Pa, followed by vacuum brazing. After brazing, the workpiece is kept warm for half an hour, and then the workpiece is transferred to an insulation box and slowly cooled to room temperature in an atmospheric environment. The formed weld is subjected to a tensile strength test, and the weld strength is obtained to be 245Mpa.

[0095] The same preassembled workpiece as above is placed in the same position of the brazing equipment and heated without changing the position of the heating device. During the brazing process, when the weld is large, a push rod is used to support the carbide block until the large weld is eliminated. The welds lacking solder are repaired in time until it is manually determined that the brazing is completed. The workpiece is then placed in an insulation box for slow cooling. After cooling to room temperature, samples are taken from the same position as the above-mentioned finished product for a tensile strength test, and the weld strength is measured to be 173Mpa.

[0096] The test results show that the brazing joints prepared by the brazing device and brazing method provided by the present solution have higher strength, which effectively improves the strength of the brazing joints of the existing brazing methods.

[0097] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A mounting structure of bulk cemented carbide and steel, characterized in that: The mounting structure comprises: Base; A fixed support, the fixed support is arranged on the base, and the fixed support can slide along the base; A stopper, the stopper is connected to the fixed support, a first mounting position is formed between the stopper and the base, a steel substrate is arranged in the first mounting position, the steel substrate is provided with a second mounting position, and a cemented carbide block is arranged in the second mounting position; The stopper part is in contact with the steel substrate at one side away from the fixed support and is in contact with the hard alloy block at one end away from the base. A second movable groove is provided on the side of the fixed support close to the first mounting position. One end of the stopper part is located inside the second movable groove and the other end is in contact with the hard alloy block. A plurality of stopper parts can be placed in the second movable groove. A plurality of hard alloy blocks can be placed on the second mounting position. Each hard alloy block is in contact with a stopper part respectively, so as to prevent the hard alloy block from moving toward the fixed support during welding. The stopper comprises: a first connecting section, the first connecting section being connected to the fixed support, and the first connecting section being movable relative to the fixed support; an adjusting device connected to the first connecting section; A stopper, the stopper is connected to the adjustment device and is disposed on a side of the adjustment device away from the base, one end of the first connecting section is embedded in the second movable groove and can move relative to the second movable groove, the other end of the first connecting section is bent and arranged vertically upward to the base, one end of the adjustment device is connected to the bent section of the first connecting section, and the other end is connected to the stopper, and the adjustment device can adjust the distance of the stopper relative to the base; The first connecting section comprises: a first connecting rod, the first connecting rod being connected to the fixed support, and at least a portion of the first connecting rod entering into the fixed support; A transfer rod, the transfer rod is connected to the first connecting rod, the transfer rod is bent toward the adjusting device, and the adjusting device is connected to the transfer rod; The regulating device comprises: An adjusting screw rod is connected with the transfer rod and is used to adjust the height of the ceramic shaft sleeve to match the height of the cemented carbide block. The transition rod has a threaded hole at one end and a blind hole at the other end. The stopper is inserted into the blind hole of the transition rod. The stopper is composed of a ceramic shaft and a ceramic sleeve. The ceramic shaft and the ceramic sleeve are detachably connected to facilitate replacement of ceramic sleeves of different thicknesses. A transition rod connected to the stopper; Wherein, the adjusting screw adjusts the distance between the transition rod and the base by rotating; There are two fixed supports, which are located at opposite sides of the base. Each fixed support is provided with at least one stopper, and the stopper also includes: A spring, one end of which is connected to the transfer rod, and the other end of which is connected to the fixed support.

2. A method for brazing a bulk cemented carbide and steel, characterized in that: The brazing method adopts the mounting structure according to claim 1, and the brazing method comprises: Pre-assembling the steel substrate and the cemented carbide block to obtain a pre-assembled workpiece; Putting the preassembled workpiece into a brazing device for brazing to obtain a welded workpiece; The welded workpiece is placed in a heat preservation box and slowly cooled to room temperature, and the surface of the welded workpiece is processed to obtain a finished workpiece.

3. The brazing method according to claim 2, characterized in that: The pre-assembling of the steel substrate and the cemented carbide block to obtain a pre-assembled workpiece comprises: Placing the steel substrate in the first installation position, and placing the cemented carbide block in the second installation position; Adjusting the stopper so that the stopper contacts the cemented carbide block; Adding brazing material and flow blocker to the weld between the steel substrate and the cemented carbide block to obtain a first mixture; The first mixture is allowed to stand for 20 to 40 minutes to obtain a pre-assembled product.

4. The brazing method according to claim 3, characterized in that: The step of placing the preassembled workpiece into a brazing device for brazing to obtain a welded workpiece comprises: Put the preassembled workpiece into a sealed space, and adjust the heating position of the heating device according to the position of the preassembled workpiece; Start the vacuum pump and adjust the relative vacuum degree of the sealed space to 10 -3 Pa; The heating device is started to raise the temperature in the sealed space to 700° C., and vacuum brazing is performed to obtain a welded workpiece.

5. The brazing method according to claim 4, characterized in that: The step of adding a brazing filler metal and a flow block to the weld between the steel substrate and the cemented carbide block to obtain a first mixture comprises: Apply paste soldering flux on the solder surface to obtain wet solder; The water and gypsum powder are mixed into a paste to form a flow barrier; The flow block is applied to the outside of the weld, and the wet brazing filler metal is placed in the weld between the steel substrate and the cemented carbide block.

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