WO2019114296A1

WO2019114296A1 - Gradient cemented carbide self-drilling screw die

Info

Publication number: WO2019114296A1
Application number: PCT/CN2018/099316
Authority: WO
Inventors: 李京达
Original assignee: 鑫京瑞钨钢（厦门）有限公司
Priority date: 2017-12-12
Filing date: 2018-08-08
Publication date: 2019-06-20
Also published as: TW201927446A; CN107775006A; CN108941575A; CN108941575B; TWI687272B

Abstract

A gradient cemented carbide self-drilling screw die, comprising a base (1) that is made from cemented carbide, a die blank (2) being provided on the base (1), and a discharge groove (3) further being provided on the base (1); the discharge groove (3) comprises a vertical groove (31) and a horizontal groove (32) that is connected to a middle portion of the vertical groove; both ends of the vertical groove (31) are in communication with two opposite front and rear side walls of the base (1), while one end of the horizontal groove (32) is in communication with a right side wall of the base (1); a top surface of the die blank (2) is flush with a top surface of the base (1), the die blank (2) sinking into an inner portion of the base (1) from a top surface of the base (1), and a left side of the die blank (2) being flush with a left side wall of the base (1); the distance between a right side of the die blank (2) and the discharge groove (3) is 1~5mm; the hardness of the die blank (2) is higher than the hardness of the base (1); the die blank (2) is combined with the base (1) by means of high temperature sintering.

Description

Gradient carbide tailing die

Technical field

The invention relates to the technical field of cemented carbides, in particular to a gradient cemented carbide tailing die.

Background technique

Cemented carbide is a material with high hardness, high strength and high wear resistance, and has been widely used in many fields of modern industry. The cemented carbide product is usually a powder metallurgy product which is sintered in a vacuum furnace or a hydrogen sintering furnace with a carbide micron-sized powder of a high hardness refractory metal as a main component. Carbide products are widely used in oil drilling, coal cutter teeth, road cold milling machine teeth, stamping dies, rolls and other fields.

Chinese patent CN103817150 discloses a gradient structure type cemented carbide roll ring comprising a roll ring outer layer and a roll ring core portion, the roll ring outer layer is disposed on the outer surface of the roll ring core portion, and the roll ring outer layer is the same as the roll ring core portion. There is an inter-melting layer between them, forming a composition gradient between the outer layer of the roll ring and the core of the roll ring, the outer layer of the roll ring and the core of the roll ring are different, and the outer layer of the roll ring after the wax is dried is ball milled and mixed. After the wax is dried, the core of the roller ring is ball-milled and mixed, and the powder is rolled into a roll ring blank, and the final product is obtained by sintering. The disadvantage is that the composite cemented carbide product is obtained by using the composition gradient, and the component diffusion due to the concentration gradient occurs during the sintering process, and the fine process difference causes the diffusion condition to be very different, which makes the final product performance consistency difficult to control.

Chinese patent CN201611158327.7 is a solution to the above problem, but after a period of use, it is found that the tail mold is in use, because the upper and lower layers are different in material and compacted, resulting in stress concentration during use. The joint surface is affected by the pure shear stress, and the joint surface is prone to cracking on both sides of the joint surface, resulting in a decrease in the service life of the mold. In response to this situation, the applicant has invented a new gradient cemented carbide tail mold after extensive research. Prepare the structure.

Summary of the invention

The present invention is directed to the improvement of the above problems in the prior art, that is, the technical problem to be solved by the present invention is to provide a gradient hard alloy drill tail die with uniform force and long service life.

In order to solve the above technical problem, the technical solution of the present invention is: a gradient cemented carbide tail die comprising a base made of cemented carbide, the base is provided with a mold blank, and the base is further provided with a mold a discharge chute, the unloading trough comprises a vertical trough and a transverse trough connecting the middle of the vertical trough, the two ends of the vertical trough are respectively connected with the opposite front and rear side walls of the base, and one end of the horizontal trough is connected with the right side wall of the base The mold blank sinks from the top surface of the base into the interior of the base, the left side of the mold blank is flush with the left side wall of the base, and the right side of the mold blank is not connected to the discharge chute. The hardness of the mold base is higher than the hardness of the base, and the mold base and the base are combined by high temperature sintering.

Further preferably, the top surface of the mold blank is flush with the top surface of the base.

Further preferably, the right side of the mold blank is separated from the discharge tank by 1 to 5 mm.

Further preferably, the top surface of the mold blank is not flush with the top surface of the base.

Further preferably, the base cemented carbide of WC powder, Co powder, Cr ₃ C ₂ powder, and constitute, wherein _{the substrate} is a WC powder particle diameter d 6-16μm.

Further preferably, the cemented carbide of the mold base is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d _top of 0.6-6 μm.

Further preferably, the discharge chute is a transverse groove.

Further preferably, the intersection line of the mold blank and the left side surface of the base is polygonal, or consists of a plurality of arcs, or is composed of a plurality of curved lines, or consists of straight lines and curved lines, or consists of straight lines and curved lines, or It consists of arcs and curves, or lines, curves, and arcs.

Further preferably, the intersection contour of the mold base and the top surface of the base is polygonal, or consists of a plurality of arcs, or consists of a plurality of curved lines, or consists of straight lines and arcs, or consists of straight lines and curves, or is composed of arcs. A line and curve composition, or a line, a curve, and an arc. Further preferably, the longitudinal section profile of the mold blank is always equal from left to right.

Further preferably, the longitudinal section profile of the mold blank is not always equal from left to right.

Compared with the prior art, the present invention has the following beneficial effects: the present invention provides a hard alloy blank with a higher hardness on a lower hardness base, and the stress condition is no longer subjected to shear stress on a horizontal surface. The service life of the mold has increased significantly.

The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

DRAWINGS

1 is a schematic view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

2 is a cross-sectional view of the gradient cemented carbide tailing die of FIG. 1 taken along line A-A of FIG. 1 according to an embodiment of the present invention.

3 is a cross-sectional view of the gradient cemented carbide tailing die of FIG. 1 taken along line B-B of FIG. 1 according to an embodiment of the present invention.

4 is a left side view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

Figure 5 is a cross-sectional view of the gradient cemented carbide tailing die of Figure 1 taken along line B-B of Figure 1 of the present invention.

6 is a left side view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

Fig. 7 is a left side view showing a gradient cemented carbide tailing die according to an embodiment of the present invention.

8 is a left side view of a six-graded cemented carbide drill tail die according to an embodiment of the present invention.

9 is a left side view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

10 is a left side view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

Figure 11 is a left side view of a gradient cemented carbide tailing die according to an embodiment of the present invention.

12 is a left side view of a ten gradient cemented carbide tailing die according to an embodiment of the present invention.

Figure 13 is a left side view of a gradient cemented carbide tailing die according to an eleventh embodiment of the present invention.

Figure 14 is a left side view of a twelve gradient cemented carbide tailing die according to an embodiment of the present invention.

Figure 15 is a schematic view of a gradient cemented carbide tailing die according to a thirteenth embodiment of the present invention.

Figure 16 is a schematic view of a four-step gradient cemented carbide tailing die according to an embodiment of the present invention.

In the figure: 1-base, 2-mold, 3-discharge trough, 31-vertical, 32-transverse.

Detailed ways

Embodiment 1 : As shown in FIG. 1 to FIG. 3 , a gradient cemented carbide tail die comprises a base 1 made of cemented carbide, and a base 2 is disposed on the base, and the base 1 is arranged on the base 1 The discharge chute 3 is further provided with a vertical groove 31 and a horizontal groove 32 connecting the middle of the vertical groove 31. The two ends of the vertical groove 31 communicate with the opposite side walls of the base 1 and the front, respectively. One end of the lateral groove 32 communicates with the right side wall of the base 1. The mold blank 2 sinks from the top surface of the base 1 into the interior of the base 1. The left side of the mold base 2 is flush with the left side wall of the base 1. The right side of the mold blank 2 is not in communication with the vertical groove 31 of the discharge chute 3, the hardness of the mold blank 2 is higher than the hardness of the base 1, and the mold base 2 and the base 1 are bonded by high-temperature sintering.

The top surface of the mold blank 2 is flush with the top surface of the base 1.

The right side of the mold blank 2 is spaced 5 mm from the vertical groove 31 of the discharge chute 3.

The cemented carbide base 1 of WC powder, Co powder, Cr ₃ C ₂ powder, and constitute, wherein _{the substrate} is a WC powder particle diameter d 6μm.

The cemented carbide of the mold blank 2 is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d _top of 0.6 μm.

The intersection contour of the mold blank 2 and the left side surface of the base 1 is semicircular.

The blanks 2 are always equal from left to right along the B-B longitudinal section profile in FIG.

The gradient cemented carbide tail mold is produced by the following steps:

Mix (1) Preparation of base 1: Weigh WC powder, Co powder and Cr ₃ C ₂ powder (or powder with VC) for raw ingredients, _{a bottom} diameter d WC powder is 6-16μm, even after mixing The raw material is subjected to wet ball milling, and after the wet ball milling, the wet ball milled mixture is subjected to the first wet sieving, the first sifted mixture is vacuum dried, and the vacuum dried mixture is subjected to the first After sieving twice, then drying into a wax to obtain a cemented carbide mixture of the base;

(2) Preparation of mold blank 2 mixture: WC powder, Co powder and Cr ₃ C ₂ powder (or VC powder) are respectively weighed into raw materials, and the WC powder has a particle size d _top of 0.6-6 μm, which will be uniformly mixed. The raw material is subjected to wet ball milling, and after the wet ball milling, the wet ball milled mixture is subjected to the first wet sieving, the first sifted mixture is vacuum dried, and the vacuum dried mixture is subjected to the first After sieving twice, then drying into a wax to obtain a cemented carbide mixture of the mold blank;

(3) Molding and pressing: firstly put the appropriate amount of the cemented carbide mixture into the molding die, apply pressure pressing of 140MPa, and press the semicircular groove and the discharge chute 3 in the upper part of the base (the relevant parameters are set according to the setting). The value is selected), and then the cemented carbide mixture of the appropriate mold blank 2 is placed in the mold and placed in the groove, and the mixture in the forming mold is compacted by applying a pressure of 100-140 MPa to obtain a gradient cemented carbide tail-molded blank;

(4) Sintering: The gradient cemented carbide tail-molded blank is heated at a rate of 1 to 3 ° C / min, firstly heated to 300 ° C and held for 250 to 300 min, and then heated to 1400-1450 ° C and kept sintered 30- After 50 min, the temperature was lowered at 1 ° C/min to obtain a gradient cemented carbide tail mold after sintering.

By providing a semi-circular high-hardness mold 2 on the lower hardness base 1, the circular arc-shaped contact surface of the mold blank 2 distributes the stress on the interface of the mold base 2 and the base 1 to avoid the shearing. The shear stress and the service life of the mold increased significantly.

Embodiment 2: As shown in FIG. 4, the difference from the first embodiment lies in the structure of the mold base 2. The intersection line between the mold blank 2 and the left side of the base 1 is U-shaped, the bottom is semi-circular, and the upper sides are The walls are vertically parallel.

The right side of the mold blank 2 and the vertical groove 31 of the discharge chute 3 are separated by 1 mm.

The cemented carbide base 1 of WC powder, Co powder, Cr ₃ C ₂ powder, and constitute, wherein _{the bottom} diameter d of WC powder 16μm.

The cemented carbide of the mold blank 2 is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d _top of 6 μm.

The rest are the same.

Embodiment 3: As shown in FIG. 1 and FIG. 5, the difference from the second embodiment lies in the structure of the mold blank 2, which is not always equal from left to right along the longitudinal profile of the B-B in FIG.

The right side of the mold blank 2 and the vertical groove 31 of the discharge chute 3 are separated by 3 mm.

The base 1 is constituted by a cemented carbide WC powder, Co powder and Cr ₃ C ₂ powder, WC powder, wherein _{the bottom} diameter d is 11 m,

The cemented carbide of the mold blank 2 is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d _top of 3.5 μm.

The rest are the same.

Embodiment 4: As shown in FIG. 6, the difference from the second embodiment is that the top surface of the mold blank 2 is not flush with the top surface of the base 1.

The right side of the mold blank 2 is spaced 4 mm from the vertical groove 31 of the discharge chute 3.

The base 1 is constituted by a cemented carbide WC powder, Co powder and Cr ₃ C ₂ powder, WC powder, wherein _{the bottom} diameter d is 13 m,

The cemented carbide of the mold blank 2 is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d _top of 3 μm.

The rest are the same.

Embodiment 5: As shown in FIG. 7, the difference from Embodiment 1 lies in the structure of the mold base 2, and the intersection line contour of the mold blank 2 and the left side surface of the base 1 is a polygon. The right side of the mold blank 2 is spaced apart from the vertical groove 31 of the discharge chute 3 by 2 mm.

The rest are the same.

Embodiment 6: As shown in FIG. 8, the difference from Embodiment 1 lies in the structure of the mold base 2, and the intersection line contour of the mold blank 2 and the left side surface of the base 1 is a polygon.

The rest are the same.

Embodiment 7: As shown in FIG. 9, the difference from Embodiment 1 lies in the structure of the mold blank 2, and the intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of a straight line and an arc.

The rest are the same.

Embodiment 8: As shown in FIG. 10, the difference from Embodiment 1 lies in the structure of the mold blank 2, and the intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of a straight line and an arc.

The rest are the same.

Embodiment 9: As shown in FIG. 11, the difference from Embodiment 1 lies in the structure of the mold blank 2, and the intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of a straight line and a curved line.

The rest are the same.

Embodiment 10: As shown in FIG. 12, the difference from Embodiment 1 lies in the structure of the mold base 2, and the intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of a plurality of arcs.

The rest are the same.

Embodiment 11: As shown in FIG. 13, the difference from Embodiment 1 lies in the structure of the mold blank 2, and the intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of an arc and a curve.

The rest are the same.

Embodiment 12: As shown in FIG. 14, the difference from Embodiment 1 lies in the structure of the mold blank 2. The intersection contour of the mold blank 2 and the left side surface of the base 1 is composed of a straight line, an arc and a curve.

The rest are the same.

Embodiment 13: As shown in FIG. 15, the difference from the first embodiment lies in the structure of the mold base 2, and the intersection contour of the top surface of the mold base 2 and the base 1 is composed of a straight line and an arc.

The rest are the same.

Embodiment 14: As shown in FIG. 16, the difference from Embodiment 1 is that the discharge chute 3 is a lateral groove. The rest are the same.

The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should fall within the scope of the present invention.

Claims

A gradient cemented carbide tailing die comprising a base made of cemented carbide, the base is provided with a mold blank, and the base is further provided with a discharge groove, the discharge groove comprises a vertical groove and a transverse groove connecting the middle portion of the vertical groove, wherein the two ends of the vertical groove are respectively connected with the opposite side walls of the front and rear of the base, and one end of the horizontal groove communicates with the right side wall of the base, wherein the mold blank is from the top surface of the base Sinking into the interior of the base, the left side of the mold blank is flush with the left side wall of the base, the right side of the mold blank is not connected to the discharge chute, and the hardness of the mold blank is higher than the hardness of the base The mold base and the base are combined by high temperature sintering.
The gradient cemented carbide tailing die according to claim 1, wherein the top surface of the mold blank is flush with the top surface of the base.
The gradient cemented carbide tailing die according to claim 1, wherein a distance between a right side surface of the mold blank and a discharge groove is 1 to 5 mm.
A gradient cemented carbide tailing die according to any of the preceding claims, wherein the top surface of the mold blank is not flush with the top surface of the base.
The gradient cemented carbide drilling module according to claim 1, wherein said base cemented carbide of WC powder, Co powder, Cr 3 C 2 powder, and constitute, wherein the substrate is a WC powder particle diameter d 6- 16 μm, the cemented carbide of the mold base is composed of WC powder, Co powder and VC powder, wherein the WC powder has a particle size d top of 0.6-6 μm.
The gradient cemented carbide tailing die according to claim 1, wherein the discharge chute is a transverse groove.
The gradient cemented carbide tailing die according to any one of claims 1 to 6, wherein the intersection of the mold base and the left side of the base has a polygonal contour, or is composed of a plurality of arcs, or Multi-segment curve composition, consisting of straight lines and arcs, or consisting of lines and curves, or consisting of arcs and curves, or lines, curves, and arcs.
The gradient cemented carbide tailing die according to any one of claims 1 to 6, wherein the intersection of the mold base and the top surface of the base has a polygonal shape, or is composed of a plurality of arcs, or is composed of a plurality of segments. The curve consists of either a line and an arc, or a line and a curve, or an arc and a curve, or a line, a curve, and an arc.
A gradient cemented carbide tailing die according to any one of claims 1 to 6, wherein the longitudinal section profile of the mold blank is always equal from left to right.
A gradient cemented carbide tailing die according to any one of claims 1 to 6, wherein the longitudinal section profile of the formwork is not always equal from left to right.