CN106761784B - A kind of polycrystalline diamond hobboing cutter cutter ring and its manufacture craft - Google Patents

Abstract

A polycrystalline diamond hob cutter ring, comprising a cutter ring base and tooth tips evenly arranged on the outer peripheral surface of the cutter ring base; wherein the mass percentages of the raw materials of the cutter ring base are: C is 0.30-0.38%, Si is 0.6-0.8%, Mn is 0.20-0.65%, Cr is 2.7-3.5%, Mo is 2.6-3.4%, V is 1.05-1.40%, Nb is 0.05-0.15%, impurity P≤0.02%, impurity S ≤0.02%, Fe balance; tooth tips are composed of cemented carbide substrate and polycrystalline diamond wear-resistant layer. The invention also discloses a support technology of polycrystalline diamond hob cutter ring. In the present invention, the cutter ring base and tooth tips are manufactured separately, and unique processing techniques are adopted respectively, so that the high impact toughness of the cutter ring base and the high compressive strength, hardness and wear resistance of the polycrystalline diamond composite sheet are combined Therefore, it can easily break rocks and has a very high service life, which also greatly improves the efficiency of construction and excavation.

Description

A polycrystalline diamond hob cutter ring and its manufacturing process

technical field

The invention belongs to the technical field of tunnel and subway construction, and in particular relates to a polycrystalline diamond hob cutter ring and a manufacturing process thereof.

Background technique

At present, the construction of mountain tunnels and urban subways using shield tunneling and TBM methods in my country has entered a period of vigorous development. Shield tunneling and TBM methods have increasingly become the first choice for tunnel construction methods due to their strong adaptability to geological conditions, fast construction speed, and less interference with the surrounding environment. , while some cities in China that are building subways often encounter hard rock formations or extremely abrasive sandstone formations with rock compressive strengths reaching or exceeding 100 MPa. Shield machines excavate in these formations. Traditional steel hob Severe wear and tear leads to frequent tool changes, increasing construction risks and engineering costs. At present, the materials commonly used for hob cutter rings are 4Cr5MoSiV1, 40CrNiMo, H13, etc., but these cutter ring materials are all made of a single alloy steel material, which has the problem of poor wear resistance or easy fracture in the excavation of hard rock and sandstone formations. For metal materials prepared under general conditions, hardness and toughness are a pair of contradictions, and the increase in hardness will inevitably reduce the toughness of the material.

Contents of the invention

In order to solve the deficiencies in the prior art, the present invention provides a polycrystalline diamond hob cutter ring with strong toughness, high hardness, high wear resistance and good compression resistance and a manufacturing process thereof.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical scheme: a polycrystalline diamond hob cutter ring, comprising a cutter ring base and tooth tips evenly arranged on the outer circumferential surface of the cutter ring base; wherein the raw materials of the cutter ring base occupy The mass percentages are: C is 0.30-0.38%, Si is 0.6-0.8%, Mn is 0.20-0.65%, Cr is 2.7-3.5%, Mo is 2.6-3.4%, V is 1.05-1.40%, Nb is 0.05～0.15%, impurity P≤0.02%, impurity S≤0.02%, Fe balance;

The tooth tip is composed of a cemented carbide substrate and a polycrystalline diamond wear-resistant layer. The mass percentages of the raw materials for the polycrystalline diamond wear-resistant layer are: 80%-82% for diamond, 6%-7% for Si, and 6%-7% for Co It is 12%-13%.

The overall hardness of the knife ring base is HRC48-53, and the impact toughness is 27-37J/cm2.

A manufacturing process of a polycrystalline diamond hob cutter ring, comprising the following steps: (1) manufacturing a cutter ring base, and uniformly setting installation grooves on the circumferential surface of the cutter ring base;

(2) Make the tip of the tooth;

(3) Evenly fix the cemented carbide substrate of the tooth tip into the installation groove of the cutter ring substrate by welding after inlaying.

Step (1) The specific production steps are:

a. The raw materials of the knife ring base body are sequentially subjected to electric furnace smelting, electroslag remelting, pre-forging, die forging, slow cooling, annealing, and rough machining to obtain a rough blank of the knife ring base body with a disc structure;

b. After high-temperature vacuum quenching, secondary high-temperature tempering, low-temperature stress relief treatment, and finishing, the rough blank of the knife ring base can obtain a knife ring base with an overall hardness of HRC48-53 and an impact toughness of 27-37J/cm2.

In step b, the rough blank of the knife ring substrate is subjected to high-temperature vacuum quenching and secondary high-temperature tempering: quenching temperature 1050°C-1070°C, quenching oil temperature 30°C-50°C, tempering temperature 600°C-620°C, 560°C Once at -570°C.

In step b, the temperature for the low-temperature stress relief treatment is 250-370°C, and the holding time is 1.5-2 hours, using a vacuum furnace or an atmosphere protection furnace.

The hob cutter ring is heated to 150-190°C in a vacuum furnace or an atmosphere protection furnace, kept for 35-50 minutes, and naturally cooled with the furnace temperature.

Step (2) The specific production steps are:

A, the batching of diamond micropowder, mixing: choose the common diamond micropowder of 50-60um grain size of 30%-35% weight, the common diamond micropowder of 30-40um grain size of 30%-35% weight, 5%-20% weight of 10 Ordinary diamond powder with a particle size of -20um and 5-20.0umCo powder with a weight of 12%-13%, and the rest is Si powder. Use a ball mill to mill the above powder for 10 hours, mix it evenly, and store it in a vacuum oven at 120°C for future use. ;

B. Cemented carbide substrate: Process the cemented carbide substrate according to the requirements of the drawings, wherein the weight content of WC is 85%-94%, and the weight content of Co is 6%-15%;

C. Assemble the diamond micropowder and cemented carbide in the pyrophyllite block: take 1.0g-2.0g of the mixed diamond micropowder and the cemented carbide matrix and compact and assemble it with a 5-ton press; place the assembled and compacted matrix in Put the pyrophyllite synthetic block into a synthetic mold composed of conductive steel rings, in which the thickness of the polycrystalline diamond wear-resistant layer is 1.0--2.0mm;

D. Synthesis under high temperature and high pressure: put the composite mold into a six-sided top diamond press, sinter and synthesize at a pressure of 5.5-6.1GPa and a temperature of 1300°C-1500°C for 5 minutes to make a polycrystalline diamond composite sheet;

E. Sand blasting treatment: remove the sintered matter on the surface of the polycrystalline diamond composite sheet;

F. Stress relief of polycrystalline diamond composite sheet: heat the polycrystalline diamond composite sheet to 200-250°C in a vacuum furnace or atmosphere protection furnace, keep it warm for 5-10 minutes, and then cool it naturally with the furnace temperature;

G. Post-processing of polycrystalline diamond composite sheet: use a grinding machine to obtain a polycrystalline diamond composite sheet after mechanical processing, so that the diameter of the cemented carbide substrate of the polycrystalline diamond composite sheet is slightly larger than the inner diameter of the installation groove, and the diameter tolerance of the cemented carbide substrate It is ±0.01mm, and the height tolerance is ±0.05mm.

Step (3) The specific production steps are: the cemented carbide substrate of the polycrystalline diamond composite sheet is embedded in the installation groove, and then the cemented carbide substrate and the knife ring substrate are welded together by brazing, and the welding temperature is 620°C-680°C , using high-strength silver solder and powdered silver brazing flux.

The polycrystalline diamond composite sheet is inlaid into the installation groove by an interference fit inlay method, and the interference is controlled at 0.05mm.

Using the above technical scheme, compared with the traditional shield cutter ring material, the present invention lowers the carbon content to 0.30-0.38%, increases the Mo content, although the overall hardness of the cutter ring base decreases to HRC48-53, but the cutter ring base The impact toughness has been greatly improved to 27~37J/cm2, which ensures the extremely high toughness of the knife ring base and avoids the breakage of the knife ring. Since the installation groove is prefabricated on the outer circumferential surface of the cutter ring base, the polycrystalline diamond composite sheet is inlaid or brazed in the installation, and the polycrystalline diamond composite sheet is made of a cemented carbide substrate and a polycrystalline diamond wear-resistant layer through a series of processing processes. made. Although the overall hardness of the cutter ring base is reduced to HRC48-53, the wear resistance is reduced, but the wear resistance of the hob cutter ring is greatly enhanced by the use of polycrystalline diamond wear-resistant layer. In the present invention, the cutter ring base and tooth tips are manufactured separately, and unique processing techniques are adopted respectively, so that the high impact toughness of the cutter ring base and the high compressive strength, hardness and wear resistance of the polycrystalline diamond composite sheet are combined Therefore, it can easily break rocks and has a very high service life, which also greatly improves the efficiency of construction and excavation.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Detailed ways

As shown in Figure 1, a kind of polycrystalline diamond hob cutter ring of the present invention, comprises cutter ring base body 1 and the tooth point that is evenly arranged on the outer peripheral surface of cutter ring base body 1; Wherein each raw material of cutter ring base body 1 occupies The mass percentages are: 0.30-0.38% for C, 0.6-0.8% for Si, 0.20-0.65% for Mn, 2.7-3.5% for Cr, 2.6-3.4% for Mo, 1.05-1.40% for V, and 0.05% for Nb ~0.15%, impurity P≤0.02%, impurity S≤0.02%, Fe balance;

The tooth tip is composed of a cemented carbide substrate 2 and a polycrystalline diamond wear-resistant layer 3. The mass percentages of the raw materials of the polycrystalline diamond wear-resistant layer 3 are: 80%-82% for diamond, 6%-7% for Si %, Co is 12%-13%.

The overall hardness of the cutter ring base 1 is HRC48-53, and the impact toughness is 27-37J/cm2.

A manufacturing process of a polycrystalline diamond hob cutter ring, comprising the following steps: (1) manufacturing a cutter ring base 1, and uniformly setting installation grooves on the circumferential surface of the cutter ring base 1;

(2) Make the tip of the tooth;

(3) Evenly fix the cemented carbide substrate 2 of the tooth tip into the installation groove of the cutter ring substrate 1 by means of inlaying and welding.

Step (1) The specific production steps are:

a. The raw materials of the knife ring base 1 are sequentially subjected to electric furnace smelting, electroslag remelting, pre-forging, die forging, slow cooling, annealing, and rough machining to obtain the rough blank of the knife ring base 1 with a disc-shaped structure;

b. After the rough blank of knife ring base 1 is subjected to high-temperature vacuum quenching, secondary high-temperature tempering, low-temperature stress relief treatment, and finishing, the knife ring base 1 with overall hardness of HRC48-53 and impact toughness of 27-37J/cm2 is obtained.

In step b, the rough blank of the knife ring base 1 is subjected to high-temperature vacuum quenching and secondary high-temperature tempering: quenching temperature 1050°C-1070°C, quenching oil temperature 30°C-50°C, tempering temperature 600°C-620°C, 560°C ℃-570℃ each once.

In step b, the temperature for the low-temperature stress relief treatment is 250-370°C, and the holding time is 1.5-2 hours, using a vacuum furnace or an atmosphere protection furnace. The hob cutter ring is heated to 150-190°C in a vacuum furnace or an atmosphere protection furnace, kept for 35-50 minutes, and naturally cooled with the furnace temperature.

Step (2) The specific production steps are:

A, the batching of diamond micropowder, mixing: choose the common diamond micropowder of 50-60um grain size of 30%-35% weight, the common diamond micropowder of 30-40um grain size of 30%-35% weight, 5%-20% weight of 10 Ordinary diamond powder with a particle size of -20um and 5-20.0umCo powder with a weight of 12%-13%, and the rest is Si powder. Use a ball mill to mill the above powder for 10 hours, mix it evenly, and store it in a vacuum oven at 120°C for future use. ;

B. Cemented carbide substrate 2: Process the cemented carbide substrate 2 according to the requirements of the drawings, wherein the weight content of WC is 85%-94%, and the weight content of Co is 6%-15%;

C. Assemble the diamond micropowder and cemented carbide in the pyrophyllite block: get 1.0g-2.0g of mixed diamond micropowder and cemented carbide substrate 2 and compact and assemble it with a 5-ton press; place the compacted substrate after assembly In the pyrophyllite synthetic block, put it into a synthetic mold composed of a conductive steel ring, wherein the thickness of the polycrystalline diamond wear-resistant layer 3 is 1.0--2.0mm;

D. Synthesis under high temperature and high pressure: put the composite mold into a six-sided top diamond press, sinter and synthesize at a pressure of 5.5-6.1GPa and a temperature of 1300°C-1500°C for 5 minutes to make a polycrystalline diamond composite sheet;

E. Sand blasting treatment: remove the sintered matter on the surface of the polycrystalline diamond composite sheet;

F. Stress relief of polycrystalline diamond composite sheet: heat the polycrystalline diamond composite sheet to 200-250°C in a vacuum furnace or atmosphere protection furnace, keep it warm for 5-10 minutes, and then cool it naturally with the furnace temperature;

G. Post-processing of polycrystalline diamond composite sheet: use a grinding machine to obtain a polycrystalline diamond composite sheet after mechanical processing, so that the diameter of the cemented carbide substrate 2 of the polycrystalline diamond composite sheet is slightly larger than the inner diameter of the installation groove, and the cemented carbide substrate 2 The diameter tolerance is ±0.01mm, and the height tolerance is ±0.05mm.

Step (3) The specific production steps are: the cemented carbide substrate 2 of the polycrystalline diamond compact is embedded in the installation groove, and the interference fit is adopted, and the interference is controlled at 0.05mm; then the cemented carbide is brazed The base body 2 is welded together with the cutter ring base body 1 at a welding temperature of 620°C-680°C, using high-strength silver solder and powdered silver brazing flux.

The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that the present invention can still be modified or equivalently replaced without departing from it. Any modifications or partial replacements within the spirit and scope of the present invention shall fall within the scope of the claims of the present invention.

Claims (7)

1. A manufacturing process of polycrystalline diamond hob cutter ring, characterized in that: The polycrystalline diamond hob cutter ring includes a cutter ring base and tooth tips evenly arranged on the outer peripheral surface of the cutter ring base; wherein the mass percentages of the raw materials of the cutter ring base are: C is 0.30-0.38%, Si is 0.6-0.8%, Mn is 0.20-0.65%, Cr is 2.7-3.5%, Mo is 2.6-3.4%, V is 1.05-1.40%, Nb is 0.05-0.15%, impurity P≤0.02%, impurity S ≤0.02%, Fe balance; The tooth tip is composed of a cemented carbide substrate and a polycrystalline diamond wear-resistant layer. The mass percentages of the raw materials for the polycrystalline diamond wear-resistant layer are: 80%-82% for diamond, 6%-7% for Si, and 6%-7% for Co 12%-13%; The overall hardness of the knife ring base is HRC48-53, and the impact toughness is 27-37J/cm2; Described manufacturing process comprises the following steps: (1) Make the base of the knife ring, and evenly arrange installation grooves on the circumferential surface of the base of the knife ring; (2) Make the tip of the tooth; (3) Evenly fix the cemented carbide substrate of the tooth tip into the installation groove of the cutter ring substrate by welding after inlaying; Step (2) The specific production steps are: A, the batching of diamond micropowder, mixing: choose the common diamond micropowder of 50-60um grain size of 30%-35% weight, the common diamond micropowder of 30-40um grain size of 30%-35% weight, 5%-20% weight of 10 Ordinary diamond powder with a particle size of -20um and 5-20.0umCo powder with a weight of 12%-13%, and the rest is Si powder. Use a ball mill to mill the above powder for 10 hours, mix it evenly, and store it in a vacuum oven at 120°C for future use. ; B. Cemented carbide substrate: Process the cemented carbide substrate according to the requirements of the drawings, wherein the weight content of WC is 85%-94%, and the weight content of Co is 6%-15%; C. Assemble the diamond micropowder and cemented carbide in the pyrophyllite block: take 1.0g-2.0g of the mixed diamond micropowder and the cemented carbide matrix and compact and assemble it with a 5-ton press; place the assembled and compacted matrix in Put the pyrophyllite synthetic block into a synthetic mold composed of conductive steel rings, in which the thickness of the polycrystalline diamond wear-resistant layer is 1.0--2.0mm; D. Synthesis under high temperature and high pressure: put the composite mold into a six-sided top diamond press, sinter and synthesize at a pressure of 5.5-6.1 GPa and a temperature of 1300°C-1500°C for 5 minutes to make a polycrystalline diamond composite sheet; E. Sand blasting treatment: remove the sintered matter on the surface of the polycrystalline diamond composite sheet; F. Stress relief of polycrystalline diamond composite sheet: heat the polycrystalline diamond composite sheet to 200-250°C in a vacuum furnace or atmosphere protection furnace, keep it warm for 5-10 minutes, and then cool it naturally with the furnace temperature; G. Post-processing of polycrystalline diamond composite sheet: use a grinding machine to obtain a polycrystalline diamond composite sheet after mechanical processing, so that the diameter of the cemented carbide substrate of the polycrystalline diamond composite sheet is slightly larger than the inner diameter of the installation groove, and the diameter tolerance of the cemented carbide substrate It is ±0.01mm, and the height tolerance is ±0.05mm. 2. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 1, characterized in that: the specific manufacturing steps of step (1) are: a. The raw materials of the knife ring base body are sequentially subjected to electric furnace smelting, electroslag remelting, pre-forging, die forging, slow cooling, annealing, and rough machining to obtain a rough blank of the knife ring base body with a disc structure; b. After high-temperature vacuum quenching, secondary high-temperature tempering, low-temperature stress relief treatment, and finishing machining, the rough blank of the knife ring base can obtain a knife ring base with an overall hardness of HRC48-53 and an impact toughness of 27-37J/cm2. 3. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 2, characterized in that: in step b, the rough blank of the cutter ring base is subjected to high-temperature vacuum quenching and secondary high-temperature tempering. The specification is: quenching temperature 1050°C-1070°C, quenching oil temperature 30°C-50°C, tempering temperature 600°C-620°C, 560°C-570°C once each. 4. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 2, characterized in that: the temperature for low-temperature stress relief treatment in step b is 250-370°C, and the holding time is 1.5-2 hours, using Vacuum furnace or atmosphere protection furnace. 5. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 4, characterized in that: the hob cutter ring is heated to 150-190° C. in a vacuum furnace or an atmosphere protection furnace, and kept for 35-50 minutes. Natural cooling with furnace temperature. 6. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 1, characterized in that: Step (3) The specific manufacturing steps are: the cemented carbide substrate of the polycrystalline diamond composite sheet is embedded in the installation groove , and then weld the cemented carbide substrate and the cutter ring substrate as a whole by brazing, the welding temperature is 620°C-680°C, and high-strength silver solder and powdered silver brazing flux are used. 7. The manufacturing process of a polycrystalline diamond hob cutter ring according to claim 6, characterized in that: the polycrystalline diamond composite sheet is embedded in the installation groove by interference fit, and the interference is controlled at 0.05mm.