Powder distributor for placing target green body, positioning piece and sintering method of rotating target

Abstract

The present invention relates to a powder distributor, a positioning member and a sintering method for a rotating target material for placing a target green body. A powder pile with a slope on the top is piled up on a support plate with auxiliary sliding powder, and then the rotating target green body is placed on the slope of the powder pile. During sintering, the shrinkage of the target green body will drive the alumina powder pile to move radially inward relative to the support plate, thereby converting the horizontal static friction between the rotating target green body and the support plate into a sliding friction. The sliding effect of the auxiliary sliding powder after forming a powder pile is better than the sliding effect of a layer of flat laying in the prior art, and can better reduce the friction resistance between the target material and the support plate, reduce the friction resistance generated when the target green body shrinks, and prevent irregular deformation and cracking of the target material caused by friction resistance.

Description

Technical Field

[0001] The invention relates to the technical field of ceramic target sintering, and in particular to a powder distributor for placing a target green body, a positioning piece and a sintering method for a rotating target. Background Art

[0002] In the traditional process of sintering rotating targets, the green body is placed vertically directly on a support plate such as alumina, and then put into a sintering furnace for sintering. During sintering, the green body of the target will shrink inward as a whole, and a large friction resistance will be generated at the contact point between the bottom of the target and the support plate. This friction resistance will prevent the bottom of the target from shrinking inward, causing the deformation amount caused by the shrinkage of the bottom of the target to be different from the deformation amount caused by the upper part, resulting in outward deformation or even cracking of the bottom of the target. The deformed and cracked parts need to be cut away during subsequent processing, which increases material loss and process costs, and affects the yield and recovery rate of the target.

[0003] There is another method that first spreads a layer of alumina powder on the support plate, and then places the green body on the alumina powder, so as to reduce the friction between the target and the support plate when the target shrinks. CN206369474U discloses a rotating ceramic target sintering device that prevents sintering deformation, including a cylindrical ceramic green body and a furnace bottom plate, and a sintering block between the ceramic green body and the furnace bottom plate. The sintering method disclosed is to set a ball layer between the ceramic green body and the sintering block, and between the sintering block and the furnace bottom plate, respectively, to convert sliding friction into rolling friction, greatly reducing friction, so that the ceramic green body can shrink freely during the shrinkage process of sintering and heating. Since the target is in a soft state during high-temperature sintering, if these two methods are used, if the target is heavy, the sintering block or the ball is easy to embed into the target at high temperature, resulting in poor sliding effect, and it is difficult to effectively prevent irregular deformation caused by friction resistance. Summary of the invention

[0004] The purpose of the present invention is to provide a powder distributor, a positioning piece and a sintering method for rotating target materials for placing target green bodies. Sintering the target green bodies by this method can reduce the friction resistance generated between the target green bodies and the support plate during the sintering process, and prevent irregular deformation and cracking of the target materials caused by friction resistance.

[0005] To achieve the above-mentioned purpose, the present invention provides a powder distributor for placing target green bodies, wherein a powder pile shaping cavity is formed at the bottom of the powder distributor, the bottom of the cavity is open, and a slope is formed at the top of the powder pile shaping cavity, so that the top of the shaped powder pile forms a slope for placing the target green bodies, and the powder on the slope will slide downward due to the gravity of the target green bodies, thereby converting the friction force between the target green bodies and the supporting plate into sliding friction force. The sliding effect of the auxiliary sliding powder after forming a powder pile is better than the sliding effect of a layer of powder laid flat in the prior art, and can better reduce the friction resistance between the target material and the supporting plate.

[0006] Beneficial effect: The present invention uses auxiliary sliding powder to pile a powder pile with a slope on the support plate, and then places the target green body on the slope of the powder pile. During sintering, the contraction of the target green body will drive the alumina powder pile to move relative to the support plate, thereby converting the static friction between the target green body and the support plate into sliding friction. The sliding effect of the auxiliary sliding powder after forming a powder pile is better than the sliding effect of a layer of flat laying in the prior art, which can better reduce the friction resistance between the target and the support plate, reduce the friction resistance generated when the target green body shrinks, and prevent irregular deformation and cracking of the target caused by friction resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a schematic diagram of the structure of the powder distributor;

[0008] Figure 2 is a cross-sectional view of a powder distributor;

[0009] Figure 3 It is a schematic diagram of the structure of the positioning part. DETAILED DESCRIPTION

[0010] The present invention is further described in detail below in conjunction with specific implementation methods.

[0011] The bearing surface of the setter plate is provided with a positioning recessed hole, which is a through hole. Figure 1 and Figure 2 The powder distributor 1 shown in the figure has a tubular center positioning portion 14 protruding downward at the center of the powder distributor 1, and its lower end protrudes downward. The powder distributor 1 is placed on the setter. The center positioning portion 14 of the powder distributor 1 is inserted into the positioning concave hole of the setter, thereby fixing the powder distributor 1 on the setter.

[0012] The powder distributor 1 includes a perforated plate 12 and a vertical outer vertical plate 11. Both the perforated plate 12 and the outer vertical plate 11 are closed circular rings. The far-center end of the perforated plate 12 is connected to the waist of the outer vertical plate 11. The perforated plate 12 and the lower part of the outer vertical plate 11 form a closed circular ring powder pile shaping cavity with an open bottom. The perforated plate 12 forms a slope, which is higher away from the center than near the center, and the angle with the horizontal plane is 45° (30-50° is acceptable). The perforated plate 12 serves as the top wall of the shaping cavity and is provided with a powder leakage hole 121. The operator puts alumina powder with a particle size of 30-60 mesh into the perforated plate 12, and the alumina powder falls into the shaping cavity from the powder leakage hole 121 until the alumina powder fills the shaping cavity, and a closed circular ring powder pile is shaped. The top of the powder pile forms a slope with an angle of 45° with the horizontal plane, and the far-center part is higher than the near-center part. The outer vertical plate 11 serves as the side wall of the powder pile shaping cavity, and the upper part forms an outer peripheral wall 111 on the outer side above the perforated plate 12 to prevent the powder from spilling to the periphery. The residual powder receiving plate 13 is connected to the end of the perforated plate 12 close to the center, and the alumina powder on the perforated plate 12 that has not fallen into the shaping cavity tilts toward the center and falls onto the residual powder receiving plate 13; the upper end of the center positioning part 14 is higher than the residual powder receiving plate 13 to form an inner surrounding wall. After the powder pile is shaped in the shaping cavity at the bottom of the powder distributor 1, the powder distributor 1 is removed, and the powder pile will remain on the firing plate.

[0013] Use Figure 3 The positioning member 2 shown includes a positioning body, a positioning column 21 protruding downward from the bottom of the positioning body, and a baffle 211 is provided on the outer wall of the positioning column 21 around the axis of the positioning column 21, and the positioning member 2 is placed on the support plate. The positioning column 21 of the positioning member 2 is inserted into the positioning concave hole of the support plate, and the baffle 211 is supported on the outer periphery of the positioning concave hole of the support plate to prevent the bottom of the positioning member body from touching the alumina powder, thereby fixing the positioning column 21 on the support plate. Then, the rotating target green body is placed on the slope of the powder pile by wrapping the outer periphery of the positioning member 2, so that the vertical axis of the rotating target green body is aligned with the positioning column 21 (i.e., aligned with the center), and then the lifting part 22 on the positioning member 2 is grasped to lift the positioning member 2. At this point, the support plate, the target green body and the alumina powder are put together to form a sintering assembly.

[0014] During sintering, the shrinkage of the target green body will drive the powder pile to move relative to the firing plate, thereby converting the larger static friction between the target green body and the firing plate into a smaller dynamic friction. The auxiliary sliding powder at the slope of the powder pile has a tendency to tilt and slide toward the center, and when it slides, it brings friction to the target green body in the direction of the center, which reduces the resistance that the target green body needs to overcome when shrinking. In this embodiment, when the rotating target green body is placed on the slope of the powder pile, the vertical axis of the rotating target is aligned with the center of the powder pile through the positioning member 2, so that the amount of auxiliary sliding powder supporting the target at each position at the bottom of the target green body is equal, so that the inward force from the auxiliary sliding powder on the bottom of the target green body in all directions is equal, so that unequal deformation in all directions of the bottom of the target can be avoided.

[0015] In this embodiment, the angle between the perforated plate 12 of the powder distributor 1 and the horizontal plane is 45°. In other embodiments, the angle may not be set to 45°, and may be selected from 30 to 50°. The angle may be adjusted according to the size of the target material. In the embodiment, a through hole as a positioning recess is provided at the vertical axis of the rotating target green body corresponding to the bearing surface of the support plate. In addition to playing a positioning role, the through hole can also allow the oxygen introduced into the sintering furnace to pass through the through hole, so that the oxygen flows evenly in the sintering furnace, and prevent the volatilization of the target material caused by oxygen loss. In other embodiments, no through hole may be provided, and a positioning protrusion is provided upwardly at the vertical axis of the rotating target green body corresponding to the bearing surface of the support plate. Accordingly, the center positioning portion 14 of the powder distributor 1 that is convex downward is changed to a center positioning hole that is concave upward, and the positioning column 21 of the positioning member 2 that is convex downward at the bottom of the positioning body is changed to a positioning hole that is concave upward, which can also play a positioning role.

[0016] In this embodiment, alumina powder is used as an auxiliary sliding powder. In other embodiments, the auxiliary sliding powder may not be alumina, but may be replaced by other materials that can be used as auxiliary sliding powder in the prior art, such as zirconium oxide. Alumina may also be used together with other materials that can be used as auxiliary sliding powder in the prior art.

Claims

1. A powder distributor (1) for placing target green bodies, characterized in that: A powder pile shaping cavity is formed at the bottom, the cavity bottom is flat and open, and a slope is formed at the top of the powder pile shaping cavity, so that the bottom of the shaped powder pile is flat and the top forms a slope for placing the target green body; The powder pile shaping cavity is arranged around the center, and the slope of the powder pile shaping cavity is higher away from the center than that of the powder pile shaping cavity near the center, so that the shaped powder pile has a slope and the auxiliary sliding powder at the slope has a tendency to slide down toward the center. The powder pile shaping cavity is in the shape of a ring around the center; The top wall of the powder pile shaping cavity is provided with a powder leakage hole (121) for powder to fall into the powder pile shaping cavity; A surplus powder receiving plate (13) is connected to the top wall of the powder pile shaping cavity near the center.

2. The powder distributor (1) according to claim 1, characterized in that: The angle between the slope formed by the top of the powder pile shaping cavity and the horizontal plane is 35-50°.

3. The powder distributor (1) according to claim 1, characterized in that: A tubular center positioning portion (14) is provided at the center, the lower end of which protrudes downward for positioning, and the upper end of which is higher than the residual powder receiving plate (13).

4. The powder distributor (1) according to claim 1, characterized in that: The side walls of the powder pile shaping cavity away from the center are vertical.

5. The powder distributor (1) according to claim 1, characterized in that: A center positioning portion (14) is convexly provided downwardly at the center, or a center positioning hole is concavely provided upwardly.

6. A method for sintering a rotating target, comprising the following steps: Step A. Spread auxiliary sliding powder on the setter plate; Step B. placing the target green body on the auxiliary sliding powder, so that the sintering plate, the target green body and the auxiliary sliding powder are put together to form a sintering assembly; Step C. taking the sintered component and sintering it; Features: Step A specifically, using the powder distributor (1) as claimed in any one of claims 1 to 5, the auxiliary sliding powder is piled into a powder pile with a flat bottom and a sloped top; Step B: Specifically, the target green body is placed on the slope of the powder pile.

7. The sintering method of a rotary target according to claim 6, characterized in that: Specifically, in step A, the auxiliary sliding powder is piled into a powder pile arranged around the center, and a slope is formed on the top of the powder pile. The slope is higher away from the center than near the center, so that the powder on the slope has a tendency to slide down toward the center.

8. The sintering method of a rotary target according to claim 7, characterized in that: The powder pile is in the shape of a ring surrounding a center.

9. The sintering method of a rotary target according to claim 7, characterized in that: Step A specifically includes placing the powder distributor (1) on the setting plate, using the powder distributor (1) to pile the auxiliary sliding powder into a powder pile with a slope on the top, and then removing the powder distributor (1).

10. The sintering method of a rotary target according to claim 9, characterized in that: Specifically, step A involves adding auxiliary sliding powder to the top wall of the powder pile shaping cavity of the powder distributor (1), so that the auxiliary sliding powder falls from the powder leakage hole (121) of the top wall into the powder pile shaping cavity to shape the powder pile.

11. The sintering method of a rotary target according to claim 6, characterized in that: The support plate is provided with a positioning recessed hole at a position on the vertical axis of the support surface corresponding to the rotating target green body; Step A specifically, the powder distributor (1) as claimed in claim 5 is placed on the setter plate, and the central positioning portion (14) of the powder distributor (1) is inserted into the positioning recessed hole of the setter plate to fix the powder distributor (1), and specifically, the auxiliary sliding powder is piled into a powder pile with a slope at the top by the powder distributor (1), and then the powder distributor (1) is removed; Specifically, in step B, a positioning member (2) is taken, wherein the positioning member (2) comprises a positioning body for being wrapped around a rotating target blank for positioning, a lifting portion (22) is provided on the top of the positioning body, and a positioning column (21) is protruding downward at the vertical axis of the bottom; the positioning member (2) is placed on the support plate, and the positioning column (21) of the positioning member (2) is inserted into the positioning recessed hole of the support plate to fix the positioning member (2), so that the target blank is wrapped around the outer periphery of the positioning member (2) and placed on the slope of the powder pile, and then the lifting portion (22) on the positioning member (2) is grasped to lift the positioning member (2).

Images