A hard alloy bead with controllable blade height and its preparation method and application

Abstract

The present invention relates to the field of cemented carbide beads, and specifically, to a cemented carbide bead with controllable cutting edge height, and a preparation method and application thereof. The preparation method of cemented carbide beads with controllable cutting edge height comprises the following steps: embedding cemented carbide particles on the outer surface of a substrate, forming a brazing material layer on the outer surface of the substrate, and obtaining a brazing material rod; the brazing material layer covers the cemented carbide particles; the brazing material layer is placed in a corrosive liquid for etching, so that the cemented carbide particles cut out at a preset height, and a bead precursor is obtained. The preparation method of cemented carbide beads is simple, easy to operate, and has high preparation efficiency. Multiple beads can be formed at one time, and the cutting edge height of the cemented carbide particles can be accurately controlled to maintain consistency in the cutting edge height; the cemented carbide particles are combined by mechanical embedding plus brazing material melting and casting, and the bonding strength between the cemented carbide particles and the substrate is high, and the service life is long.

Description

Technical Field

[0001] The invention relates to the field of cemented carbide beads, and in particular to a cemented carbide bead with controllable cutting edge height, and a preparation method and application thereof. Background Art

[0002] Carbide beads are a layer of carbide particles prepared on the surface of the steel matrix, and used as a wear-resistant and cutting working layer. Carbide beads are mainly used for cutting underwater reinforced concrete and cutting steel cables and sunken ships.

[0003] The existing preparation methods of cemented carbide beads are mainly flame brazing and furnace brazing. During flame brazing, the heating efficiency is slow due to the coarseness of the steel matrix itself. It depends entirely on the welder's operating skills and eyesight to control the height of the cemented carbide particles. It often takes more than 3 hours to weld a cemented carbide bead. During furnace brazing, although multiple cemented carbide beads can be formed at one time, due to the effect of gravity, the brazing material layer is prone to turbulence, and the height of the cemented carbide beads is more difficult to control, resulting in many cemented carbide particles not coming out of the edge, low cutting efficiency; or the height of the cemented carbide particles is too high, resulting in blade breakage during the cutting process.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In order to solve the problems existing in the prior art such as inconsistent cutting height of cemented carbide particles, uncontrollable cutting height of cemented carbide particles, long preparation time and turbulent flow of solder liquid, the present invention provides a cemented carbide bead with controllable cutting height and a preparation method thereof.

[0006] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0007] One aspect of the present invention relates to a method for preparing a cemented carbide bead with controllable blade height, comprising the following steps:

[0008] Embedding cemented carbide particles on the outer surface of the substrate, forming a brazing material layer on the outer surface of the substrate, and obtaining a brazing material rod; the brazing material layer covers the cemented carbide particles;

[0009] The brazing material layer is placed in a corrosive solution for etching, so that the cemented carbide particles are cut out according to a preset height to obtain a bead precursor.

[0010] The method for preparing the cemented carbide beads is simple, easy to operate, and has high preparation efficiency. The cutting height of the cemented carbide particles can be accurately controlled to maintain consistency of the cutting height.

[0011] Preferably, the specific process of forming the solder layer on the outer surface of the substrate includes:

[0012] Fixing the substrate embedded with the cemented carbide particles at the center of the mold and sealing the lower end of the mold;

[0013] The solder liquid is injected into the gap between the mold and the substrate, and after cooling and solidification, the solder layer is formed on the outer surface of the substrate.

[0014] Preferably, after the etching, the cutting edge height of the cemented carbide particles is 1 / 4 to 1 / 3 of the height of the cemented carbide particles.

[0015] Preferably, the thickness of the brazing material layer formed on the outer surface of the substrate is greater than 1 to 2 mm of the height of the cemented carbide particles.

[0016] Preferably, the solder layer comprises at least one of BCu40MnNi, BCu45MnNi or BCu50MnNi.

[0017] Preferably, the outer surface of the substrate is provided with a plurality of grooves, and the cemented carbide particles are embedded in the grooves.

[0018] Preferably, the slot includes: a T-slot, a dovetail slot or a trapezoidal slot.

[0019] Preferably, the depth of the groove is 1 / 4 to 1 / 3 of the height of the cemented carbide particles.

[0020] Preferably, the height of the cemented carbide particles is 6-8 mm.

[0021] Preferably, the distance between two adjacent cemented carbide particles is 4-6 mm.

[0022] Preferably, the material of the cemented carbide particles includes at least one of YG6, YG8, YG15 or YG20.

[0023] Preferably, the etching solution includes: aqua regia or concentrated hydrochloric acid with hydrogen peroxide.

[0024] Preferably, when the length of the bead precursor is equal to a preset length, the bead precursor is the cemented carbide bead.

[0025] Preferably, when the length of the bead precursor is equal to n times of the preset length, the method for preparing the cemented carbide beads further comprises cutting the bead precursor to obtain n cemented carbide beads.

[0026] Preferably, the etching specifically includes:

[0027] The solder rod is placed on a rotating bracket, the solder layer is immersed in the etching solution, and the solder rod is rotated to etch the solder layer.

[0028] Another aspect of the present invention also relates to the cemented carbide beads prepared by the method for preparing the cemented carbide beads with controllable cutting edge height.

[0029] The cemented carbide beads have high bonding strength between the cemented carbide particles and the matrix, and the cutting edge heights of the cemented carbide particles are consistent.

[0030] Another aspect of the present invention also relates to a rope saw, including the hard alloy beads prepared by the method for preparing the hard alloy beads with controllable blade height or the hard alloy beads.

[0031] The rope saw has a long service life and high cutting efficiency.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) The method for preparing cemented carbide beads provided by the present invention comprises the following steps: embedding cemented carbide particles on the surface of a substrate, casting a brazing material liquid between the substrate and a mold, and performing melt casting brazing to form a brazing material layer. Compared with simple brazing or mechanical embedding, the cemented carbide particles have high bonding strength and a long service life of the beads. The cutting edge height of the cemented carbide particles can be regulated by adjusting the depth of the brazing material layer entering the corrosive liquid, and the controllability is strong. The method can obtain a relatively long cutting edge brazing material rod, which can be cut into beads as required. Compared with traditional flame brazing, the preparation method has a higher preparation efficiency.

[0034] (2) The cemented carbide beads provided by the present invention have controllable and consistent cutting edge heights of the cemented carbide particles, and high bonding strength between the cemented carbide particles and the substrate;

[0035] (3) The rope saw provided by the present invention has a long service life and high cutting efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 A schematic diagram of a device for preparing a cemented carbide beaded etched blade provided by the present invention;

[0038] Figure 2 A schematic diagram of the structure of cemented carbide brazing beads provided by the present invention;

[0039] Figure 3The morphology of the beads provided by the present invention during the preparation process (the left picture shows the morphology before corrosion, and the right picture shows the morphology after corrosion);

[0040] Figure 4 Comparison of the cutting edge heights of cemented carbide particles on the surface of beads provided by the present invention (a is the beads of Example 1, b is the flame brazed beads, and c is the furnace brazed beads).

[0041] Reference numerals:

[0042] 1-corrosion liquid tank, 2-corrosion liquid, 3-solder layer, 4-hard alloy particles, 5-substrate, 6-cover plate, 7-rotating shaft, 8-coupling, 9-motor, 10-graphite mold. DETAILED DESCRIPTION

[0043] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be understood by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0044] One aspect of the present invention relates to a method for preparing a cemented carbide bead with controllable blade height, comprising the following steps:

[0045] The cemented carbide particles 4 are embedded on the outer surface of the substrate 5, and a brazing material layer 3 is formed on the outer surface of the substrate 5 to obtain a brazing material rod; the brazing material layer 3 covers the cemented carbide particles 4;

[0046] The brazing material layer 3 is placed in the corrosive solution 2 for etching, so that the cemented carbide particles 4 are cut out according to a preset height, thereby obtaining a bead precursor.

[0047] The preparation method of the cemented carbide beads comprises the following steps: embedding the cemented carbide particles 4 on the surface of the substrate 5, casting the brazing material liquid between the substrate 5 and the mold for melt-cast brazing to form the brazing material layer 3, which is beneficial to improving the bonding strength between the cemented carbide particles 4 and the substrate 5; adjusting the depth of the brazing material layer 3 entering the corrosive liquid 2 to control the cutting edge height of the cemented carbide particles 4, and having strong controllability; compared with traditional flame brazing, the preparation method has higher preparation efficiency.

[0048] The method for preparing the cemented carbide beads comprises the following steps: firstly processing a regularly arranged T-shaped groove on the surface of a substrate 5, uniformly embedding cemented carbide particles 4 and placing the beads at the center of a mold cavity, then injecting solder molten metal into the gap between the mold cavity and the substrate 5, cooling the solder rod to form a solder rod, and finally placing the solder rod in an etching liquid tank 1, adjusting the depth of the solder rod immersed in the etching liquid 2, rotating the solder rod, etching a blade, and finally cutting the beads one by one. The method has a high preparation efficiency and can form multiple beads at one time.

[0049] In some specific embodiments, the specific process of forming the solder layer 3 on the outer surface of the substrate 5 includes:

[0050] The substrate 5 embedded with the cemented carbide particles 4 is fixed to the center of the mold, and the lower end of the mold is sealed;

[0051] The solder liquid is injected into the gap between the mold and the substrate 5 , and after cooling and solidification, a solder layer 3 is formed on the outer surface of the substrate 5 .

[0052] In some specific implementations, after the etching, the cutting edge height of the cemented carbide particles 4 is 1 / 4 to 1 / 3 of the height of the cemented carbide particles 4 .

[0053] In some specific embodiments, the thickness of the brazing material layer 3 formed on the outer surface of the substrate 5 is greater than 1 to 2 mm of the height of the cemented carbide particles 4 .

[0054] In some specific embodiments, the solder layer 3 includes at least one of BCu40MnNi, BCu45MnNi or BCu50MnNi.

[0055] In some specific implementations, the outer surface of the substrate 5 is provided with a plurality of grooves, and the cemented carbide particles 4 are embedded in the grooves.

[0056] In some specific implementations, the slot includes: a T-slot, a dovetail slot, or a trapezoidal slot.

[0057] In some specific embodiments, the T-shaped groove matches the shape of the cemented carbide particles 4 , is wide at the bottom and narrow at the top, has a depth of 1 / 4 to 1 / 3 of the height of the cemented carbide particles 4 , and is in the shape of spiral rings or circular rings with equal spacing along the substrate 5 .

[0058] In some specific implementations, the mold cavity matches the substrate 5 embedded with cemented carbide particles 4, with a gap of 1 to 2 mm, and the material is graphite.

[0059] In some specific implementations, the depth of the groove is 1 / 4 to 1 / 3 of the height of the cemented carbide particle 4 .

[0060] In some specific implementations, the height of the cemented carbide particles 4 is 6-8 mm.

[0061] In some specific implementations, the distance between two adjacent cemented carbide particles 4 is 4-6 mm.

[0062] In some specific implementations, the material of the cemented carbide particles 4 includes at least one of YG6, YG8, YG15 or YG20.

[0063] In some specific implementations, the etching solution 2 includes: aqua regia or concentrated hydrochloric acid with hydrogen peroxide.

[0064] In some specific embodiments, aqua regia is composed of concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:1.

[0065] In some specific embodiments, the hydrogen peroxide and concentrated hydrochloric acid include 30% hydrogen peroxide and 36% concentrated hydrochloric acid, and the mass ratio of hydrogen peroxide to concentrated hydrochloric acid is 1:1.

[0066] In some specific embodiments, when the length of the bead precursor is equal to a preset length, the bead precursor is the cemented carbide bead.

[0067] In some specific embodiments, when the length of the bead precursor is equal to n times the preset length, the method for preparing the cemented carbide beads further comprises cutting the bead precursor to obtain n cemented carbide beads. In some specific embodiments, etching specifically comprises:

[0068] The solder rod is placed on a rotating bracket, the solder layer 3 is immersed in the etching solution 2, and the solder rod is rotated to corrode the solder layer 3.

[0069] In some specific embodiments, the method for preparing cemented carbide beads provided by the present invention is as follows: Figure 1 As shown, the following steps are included:

[0070] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine spiral, annular, or vertically arranged T-shaped grooves with equal spacing;

[0071] Step 2: embedding the cemented carbide particles 4 into the T-shaped grooves on the surface of the substrate 5 at equal intervals;

[0072] Step 3: fix the matrix 5 embedded with hard particles in the center of the graphite mold 10, maintain a certain gap, and seal the lower end with high temperature resistant cement;

[0073] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and after cooling and solidification, break the graphite mold 10 and demould it to obtain a brazing material rod;

[0074] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in the aqua regia etching solution 2 to a certain depth, and slowly rotate and etch for a certain period of time before cutting;

[0075] Step 6: Rinse the brazing material rod that has been cut in step 5 with plenty of clean water, sandblast and cut to obtain carbide beads.

[0076] In some specific implementations, the certain spacing of the T-slots in step 1 is 4 to 6 mm.

[0077] In some specific implementations, the average spacing in step 2 is 4 to 6 mm.

[0078] In some specific implementations, the certain gap in step three ranges from 1 to 2 mm.

[0079] In some specific implementations, the certain depth in step 5 determines the cutting height of the cemented carbide particles 4, and the certain time is 3 to 5 hours.

[0080] In a specific embodiment, a device for preparing a cemented carbide beaded etching blade includes: a corrosion liquid tank 1, a cover plate 6, a rotating shaft 7, a coupling 8 and a motor 9.

[0081] Another aspect of the present invention also relates to a method for preparing a cemented carbide bead with controllable cutting edge height. Figure 2 shown.

[0082] The cutting edge height of the cemented carbide particles 4 of the cemented carbide beads is controllable and consistent, and the bonding strength between the cemented carbide particles and the matrix is ​​high.

[0083] Another aspect of the present invention also relates to a wire saw, including a hard alloy bead prepared by the method for preparing a hard alloy bead with controllable blade height or a hard alloy bead.

[0084] The embodiments of the present invention will be described in detail below with reference to specific examples and comparative examples.

[0085] Example 1

[0086] The method for preparing a cemented carbide bead with controllable cutting edge height provided in this embodiment comprises the following steps:

[0087] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine a spiral annular T-shaped groove with a spacing of 5 mm and a depth of 1.5 mm;

[0088] Step 2: embed the cemented carbide particles 4 into the T-shaped grooves on the surface of the steel rod at an equal interval of 4 mm. The cemented carbide particles 4 are made of YG6, have a height of 6 mm, and a blade height of 0.5 mm. The cemented carbide particles 4 are embedded in the T-shaped grooves on the surface of the substrate 5 in a spiral ring shape. The depth of the T-shaped grooves is 1 / 4 of the height of the cemented carbide particles 4, and the cemented carbide particles 4 are arranged at an equal interval in the T-shaped grooves.

[0089] Step 3: fix the substrate 5 embedded with cemented carbide particles 4 to the center of the graphite mold 10, keep a 1mm gap on one side, and seal the lower end with high temperature resistant cement;

[0090] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and form a brazing material layer 3 on the outer surface of the substrate 5 after cooling and solidification. The thickness of the brazing material layer 3 is 1 mm. Break the graphite mold 10 and demould it to obtain a brazing material rod such as Figure 3 As shown;

[0091] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in aqua regia to a depth of 1.5 mm, rotate slowly at a speed of 10 r / h, and remove the blade after etching for 3 hours. The morphology after etching is as follows: Figure 3 As shown, the corrosion rate of 0.5 mm / h multiplied by the corrosion time of 3 h equals the corrosion depth of 1.5 mm, and the height of the hard alloy particle 4 is 1.5 mm minus the gap of 1 mm, and the height of the hard alloy particle 4 is 0.5 mm;

[0092] Step 6: Rinse the brazing material rod that has been cut in step 5 with a large amount of clean water, sandblast and cut to obtain a number of cemented carbide beads.

[0093] Example 2

[0094] The method for preparing a cemented carbide bead with controllable cutting edge height provided in this embodiment comprises the following steps:

[0095] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine a circular T-shaped groove with a spacing of 6 mm and a depth of 1.75 mm;

[0096] Step 2: embed the cemented carbide particles 4 into the T-shaped grooves on the surface of the steel rod at an equal interval of 6 mm. The cemented carbide particles 4 are made of YG8, have a height of 7 mm, and a blade height of 1 mm. The cemented carbide particles 4 are embedded in the trapezoidal grooves on the surface of the substrate 5 in a circular ring shape. The depth of the T-shaped grooves is 1 / 4 of the height of the cemented carbide particles 4, and the cemented carbide particles 4 are arranged at an equal interval in the T-shaped grooves.

[0097] Step 3: fix the substrate 5 embedded with cemented carbide particles 4 to the center of the graphite mold 10, keep a 1.5mm gap on one side, and seal the lower end with high temperature resistant cement;

[0098] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and form a brazing material layer 3 on the outer surface of the substrate 5 after cooling and solidification. The thickness of the brazing material layer 3 is 1.5 mm. Break the graphite mold 10 and demould it to obtain a brazing material rod;

[0099] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in hydrogen peroxide concentrated hydrochloric acid to a depth of 2.5 mm, rotate slowly at a speed of 10 r / h, and remove the solder after etching for 5 hours;

[0100] Step 6: Same as Example 1.

[0101] Example 3

[0102] The method for preparing a cemented carbide bead with controllable cutting edge height provided in this embodiment comprises the following steps:

[0103] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine a vertical linear T-shaped slot with a spacing of 6 mm and a depth of 2 mm;

[0104] Step 2: embed the cemented carbide particles 4 into the T-shaped grooves on the surface of the steel rod at an equal interval of 6 mm. The cemented carbide particles 4 are made of YG15, have a height of 8 mm, and a blade height of 1 mm. The cemented carbide particles 4 are embedded in the T-shaped grooves on the surface of the substrate 5 in a vertical straight line. The depth of the T-shaped grooves is 1 / 4 of the maximum side length of the cemented carbide particles 4. The cemented carbide particles 4 are arranged at an equal interval in the dovetail groove.

[0105] Step 3: fix the substrate 5 embedded with cemented carbide particles 4 to the center of the graphite mold 10, keep a 1mm gap on one side, and seal the lower end with high temperature resistant cement;

[0106] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and form a brazing material layer 3 on the outer surface of the substrate 5 after cooling and solidification. The thickness of the brazing material layer 3 is 1 mm. Break the graphite mold 10 and demould it to obtain a brazing material rod;

[0107] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in aqua regia to a depth of 2 mm, rotate slowly at a speed of 10 r / h, and remove the solder rod after 4 hours of corrosion;

[0108] Step 6: Same as Example 1.

[0109] Example 4

[0110] The method for preparing a cemented carbide bead with controllable cutting edge height provided in this embodiment comprises the following steps:

[0111] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine a spiral annular T-shaped groove with a spacing of 5 mm and a depth of 2 mm;

[0112] Step 2: embed the cemented carbide particles 4 into the T-shaped grooves on the surface of the steel rod at an equal interval of 5 mm. The cemented carbide particles 4 are made of YG20, have a height of 6 mm, and a blade height of 0.5 mm. The cemented carbide particles 4 are embedded in the T-shaped grooves on the surface of the substrate 5 in a spiral ring shape. The depth of the T-shaped grooves is 1 / 3 of the height of the cemented carbide particles 4, and the cemented carbide particles 4 are arranged at an equal interval in the T-shaped grooves.

[0113] Step 3: fix the substrate 5 embedded with cemented carbide particles 4 to the center of the graphite mold 10, keep a 2mm gap on one side, and seal the lower end with high temperature resistant cement;

[0114] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and form a brazing material layer 3 on the outer surface of the substrate 5 after cooling and solidification. The thickness of the brazing material layer 3 is 2 mm, and the graphite mold 10 is broken and demolded to obtain a brazing material rod;

[0115] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in aqua regia to a depth of 2.5 mm, rotate slowly at a speed of 10 r / h, and remove the solder rod after etching for 5 hours;

[0116] Step 6: Same as Example 1.

[0117] Example 5

[0118] The method for preparing a cemented carbide bead with controllable cutting edge height provided in this embodiment comprises the following steps:

[0119] Step 1: Clamp the substrate 5 on a lathe and use a T-shaped milling cutter to machine a circular T-shaped groove with a spacing of 8 mm and a depth of 2 mm;

[0120] Step 2: Evenly embed the carbide particles 4 into the T-shaped grooves on the surface of the steel rod at an equal interval of 6 mm. The material of the carbide particles 4 is YG8, the height is 8 mm, and the height of the blade is 1.5 mm. The carbide particles 4 are embedded in the T-shaped grooves on the surface of the substrate 5 in a circular ring shape. The depth of the T-shaped grooves is 1 / 4 of the height of the carbide particles 4, and the carbide particles 4 are arranged at an equal interval in the T-shaped grooves.

[0121] Step 3: fix the substrate 5 embedded with cemented carbide particles 4 to the center of the graphite mold 10, keep a 1mm gap on one side, and seal the lower end with high temperature resistant cement;

[0122] Step 4: Place the brazing material in a graphite crucible and melt it into a brazing material liquid, inject it into the gap between the mold and the steel rod in step 3, and form a brazing material layer 3 on the outer surface of the substrate 5 after cooling and solidification. The thickness of the brazing material layer 3 is 1 mm. Break the graphite mold 10 and demould it to obtain a brazing material rod;

[0123] Step 5: Place the solder rod from step 4 on a rotating bracket, immerse the solder layer 3 in aqua regia to a depth of 2.5 mm, rotate slowly at a speed of 10 r / h, and remove the solder rod after etching for 5 hours;

[0124] Step 6: Same as Example 1.

[0125] Comparative Example 1

[0126] The existing flame brazed cemented carbide beads are spot welded to the surface of the steel substrate with cemented carbide particles at equal intervals, and then a layer of brazing paste is applied, the thickness of which is 3 / 4 to 2 / 3 of the height of the cemented carbide particles. The brazing paste can be silver brazing paste or copper brazing paste. The brazing paste layer is slowly and evenly heated with a flame gun to melt it and form a brazing metallurgical layer, thereby obtaining cemented carbide beads. During the flame heating process, the neutral flame has high heating efficiency, a small heating area, and low brazing efficiency.

[0127] Comparative Example 2

[0128] The existing furnace brazed cemented carbide beads. Spot weld the cemented carbide particles at equal intervals on the surface of the steel substrate, and then apply a layer of brazing paste with a thickness of 3 / 4 to 2 / 3 of the height of the cemented carbide particles. The brazing paste can be silver brazing paste or copper brazing paste, and then vertically placed in a resistance furnace for heating and welding to obtain beads. The brazing paste melts, flows turbulently and spreads down under the action of gravity, causing the depth of the brazing metallurgical layer covering the cemented carbide particles to be uneven, and the height of the edge is also uneven.

[0129] Experimental Example 1

[0130] In order to investigate the consistency of the cutting edge height of the cemented carbide beads of the embodiment of the present invention and the comparative example, the morphologies of different cemented carbide beads were compared, and the beads were cut into standard tensile specimens for mechanical property tests (the solder was the same, BCu40MnNi solder), and the bonding strength between the cemented carbide particles 4 and the matrix 5 was tested. The test results are shown in Tables 1 and Figure 4 .

[0131] Table 1 Bonding strength of cemented carbide beads

[0132] Bead Type Bonding strength between hard particles and matrix / MPa Example 1 245 Example 2 258 Example 3 265 Example 4 246 Example 5 272.3 Comparative Example 1 220 Comparative Example 2 185

[0133] It can be seen from Table 1 that the bonding strength between the cemented carbide particles 4 and the matrix 5 in the beads of the embodiment is higher than that of the comparative example.

[0134] Depend on Figure 4It can be seen that the cutting edge height of the cemented carbide particles 4 on the surface of the beads in Example 1 is highly consistent, while the cutting edge height of the flame-brazed cemented carbide beads varies, some are too high and some are too low; when brazing in the furnace, the thickness of the brazing material on the surface of the beads is uneven, the brazing material flows to the bottom of the beads, and the coating depth of the cemented carbide particles 4 is inconsistent, resulting in low bonding strength.

[0135] Experimental Example 2

[0136] In order to investigate the efficiency of the preparation method of the present invention and the flame brazing preparation method, 50 cemented carbide beads with an outer diameter of 108 mm and a height of 100 mm were prepared by the two methods respectively. When flame brazing, each bead took 3 hours on average, and about 150 hours were required; when the method of the embodiment was used for preparation, a 1.1-meter-long substrate 5 was used for preparation (0.1-meter-long cutting consumption surplus), and one substrate 5 can be cut into 10 beads, which requires 5 preparations, each time taking 15 hours (processing T-slots for 2 hours, embedding hard particles for 2 hours, smelting molten metal and casting and cooling for 1 hour, and etching the blade for 8 hours), about 75 hours, which is 2 times more efficient than flame brazing.

[0137] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A method for preparing a cemented carbide bead with controllable blade height, characterized in that: The following steps are involved: Embedding cemented carbide particles on the outer surface of the substrate, forming a brazing material layer on the outer surface of the substrate, and obtaining a brazing material rod; the brazing material layer covers the cemented carbide particles; The brazing material layer is placed in a corrosive solution for etching, so that the cemented carbide particles are cut out according to a preset height to obtain a beaded precursor; The etching specifically includes: Placing the solder rod on a rotating bracket, immersing the solder layer in the etching solution, and rotating the solder rod to etch the solder layer; The specific process of forming the solder layer on the outer surface of the substrate includes: Fixing the substrate embedded with the cemented carbide particles at the center of the mold and sealing the lower end of the mold; The solder liquid is injected into the gap between the mold and the substrate, and after cooling and solidification, the solder layer is formed on the outer surface of the substrate.

2. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: After the etching, the cutting edge height of the cemented carbide particles is 1 / 4 to 1 / 3 of the height of the cemented carbide particles.

3. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The thickness of the brazing material layer formed on the outer surface of the substrate is greater than 1 to 2 mm of the height of the cemented carbide particles.

4. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The solder layer includes at least one of BCu40MnNi, BCu45MnNi or BCu50MnNi.

5. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: A plurality of slots are arranged on the outer surface of the substrate, and the cemented carbide particles are embedded in the slots.

6. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 5, characterized in that: The slot includes: a T-shaped slot, a dovetail slot or a trapezoidal slot.

7. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 5, characterized in that: The depth of the groove is 1 / 4 to 1 / 3 of the height of the cemented carbide particles.

8. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The height of the cemented carbide particles is 6 to 8 mm.

9. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The distance between two adjacent cemented carbide particles is 4-6 mm.

10. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The material of the cemented carbide particles includes at least one of YG6, YG8, YG15 or YG20.

11. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: The corrosive liquid includes: aqua regia or hydrogen peroxide and concentrated hydrochloric acid.

12. The method for preparing a cemented carbide bead with controllable cutting edge height according to claim 1, characterized in that: When the length of the bead precursor is equal to the preset length, the bead precursor is the cemented carbide bead; When the length of the bead precursor is equal to n times the preset length, the method for preparing the cemented carbide beads further comprises cutting the bead precursor to obtain n cemented carbide beads.

13. Cemented carbide beads prepared by the method for preparing cemented carbide beads with controllable cutting edge height as claimed in any one of claims 1 to 12.

14. A wire saw, characterized in that: The present invention relates to a cemented carbide bead prepared by the method for preparing a cemented carbide bead with controllable cutting edge height as described in any one of claims 1 to 12 or a cemented carbide bead as described in claim 13.

Images