Movable block type chilling block for aluminum alloy metal mold casting

Abstract

The invention discloses a loose piece type chilling block for aluminum alloy metal mold casting, and particularly relates to the technical field of metal casting, the loose piece type chilling block comprises a chilling block body, the chilling block body is made of a material with the thermal conductivity coefficient larger than or equal to 200 W / (m.K), one end of the chilling block body is provided with a transverse vent hole and two threaded holes, and the other end of the chilling block body is provided with a through hole; one end of the chilling block body is provided with a shell core inclined plane, the other end of the chilling block body is provided with a working inclined plane flush with the shell core inclined plane, a plurality of rib grooves are formed in the working inclined plane, exhaust grooves are formed in the upper side and the lower side of the chilling block body, and a positioning hole and a longitudinal vent hole are formed in the upper side of the chilling block body. The rib grooves and the exhaust grooves are additionally designed, so that the cooling efficiency and the exhaust effect are improved, shrinkage porosity, shrinkage cavities and gas shrinkage cavities are avoided, the longitudinal ventilation and exhaust holes and the transverse ventilation and exhaust holes are formed, the gas diffusion capacity is enhanced, meanwhile, heat dissipation is assisted, local cooling is accelerated, local thermal stress can be relieved, and the crack risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of metal casting, and particularly relates to a loose-piece chill for aluminum alloy permanent mold casting. Background Art

[0002] Aluminum alloy permanent mold casting is different from aluminum alloy die casting and low-pressure casting. Die casting and low-pressure casting are formed under pressure, while aluminum alloy permanent mold casting is formed without pressure or under gravity. During the process of aluminum alloy permanent mold casting, shrinkage porosity, shrinkage cavity and other defects are likely to occur in the thick and large parts of the casting due to the difference in solidification rate, seriously affecting the mechanical properties and yield rate of the casting. In traditional processes, as a key chilling element, the chill regulates the temperature gradient by accelerating local solidification. A chill refers to a chilling object placed inside the cavity, on the cavity surface and inside the mold to accelerate the local cooling rate of the casting. The chill is used in conjunction with the gating system and riser system to control the solidification sequence of the casting to obtain a qualified casting. Chills are divided into internal chills and external chills.

[0003] Currently, conventional chills are mostly made of cast iron or ordinary steel, and their thermal conductivity is difficult to meet the requirements of high-speed solidification of aluminum alloy. Moreover, the traditional chill body lacks a thermal stress release structure and is prone to microcracks under repeated thermal cycles. The average service life is only 10 - 15 times before replacement. At the same time, most existing chills adopt a flat contact structure, and gases in the cavity and gases precipitated during solidification are likely to accumulate at the chill-casting interface during the pouring process, resulting in a relatively high defect rate of gas shrinkage cavities. Summary of the Invention

[0004] The purpose of the present invention is to provide a loose-piece chill for aluminum alloy permanent mold casting to solve the above deficiencies in the technology.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A loose-piece chill for aluminum alloy permanent mold casting, comprising: A chill body made of a material with a thermal conductivity coefficient ≥ 200 W / (m·K). One end of the chill body is provided with a transverse vent hole and two threaded holes. The other end of the chill body is provided with a working inclined surface flush with the shell core inclined surface. Multiple rib grooves are provided on the working inclined surface. Exhaust grooves are provided on both the upper and lower sides of the chill body. A positioning hole and a longitudinal vent hole are provided on the upper side of the chill body.

[0006] Preferably, the chill body is processed from a copper alloy material with high thermal conductivity. Copper alloy has high thermal conductivity, can quickly absorb the heat of the casting, shorten the solidification time, and at the same time, copper alloy has good mechanical strength and can withstand the thermal stress impact during the casting process; The chill body can also be processed from other materials with high thermal conductivity.

[0007] Preferably, the number of the rib grooves is set to seventeen. The rib grooves are parallel to the working inclined surface, and the distance between two adjacent rib grooves is 1 mm. The rib grooves increase the effective cooling area by more than 40%. Combining with the high thermal conductivity of the copper alloy, the directional solidification of the 1 / 3 area of the flange surface is accelerated. The rib grooves and the core form a gap channel to synchronously discharge the cavity gas and the gas precipitated during the solidification process, avoiding the shrinkage cavity defect.

[0008] Preferably, the exhaust grooves are arranged along the length direction of the chill body. The number of the exhaust grooves is set to three. Two of the exhaust grooves are arranged on the upper side of the chill body, and the remaining one exhaust groove is arranged on the lower side of the chill body. The radiative heat dissipation on the surface of the groove body and the convective heat dissipation inside cooperate to reduce the concentration of thermal stress.

[0009] Preferably, the depth of the exhaust groove is 0.5 mm, and the exhaust groove communicates with the corresponding rib groove. The combination of the exhaust groove and the rib groove not only enhances the exhaust effect, but also accelerates the local cooling by increasing the heat dissipation area, improving the density of the casting.

[0010] Preferably, the upper end ports of the positioning holes and the longitudinal through exhaust holes are located between the two exhaust grooves on the upper side of the chill body. The positioning holes and the longitudinal through exhaust holes penetrate through the upper and lower sides of the chill body. The setting of the positioning holes realizes the precise alignment of the movable chill in the mold, ensures the accurate matching position of the chill with the core and the shell core, effectively controls the cooling area, and avoids uneven cooling caused by misalignment. The longitudinal through exhaust holes cooperate with the directional cooling of the chill, can relieve the local thermal stress, reduce the risk of cracks, and optimize the feeding path at the same time.

[0011] Preferably, the transverse through exhaust holes are arranged in the middle of the side of the chill body far from the working inclined surface. The transverse through exhaust holes communicate with the longitudinal through exhaust holes. The two threaded holes are symmetrically distributed in front of and behind the transverse through exhaust holes. The transverse through exhaust holes cooperate with the directional cooling of the chill, can relieve the local thermal stress, reduce the risk of cracks, and optimize the feeding path at the same time. The setting of the threaded holes realizes the non-destructive disassembly, and the number of repeated uses can reach more than 50 times, improving the service life compared with the traditional knocking disassembly.

[0012] Preferably, the surface of the chill body is sprayed with a graphite-based refractory coating to prevent the copper alloy from adhering to the casting.

[0013] In the above technical solution, the technical effects and advantages provided by the present invention are as follows: The movable chill improves the cooling efficiency and the exhaust effect through the design of increasing the rib grooves and the exhaust grooves, and avoids the generation of porosity, shrinkage cavity and shrinkage cavity defect. This movable chill is made by processing a copper alloy material with a high thermal conductivity coefficient. The copper alloy has high thermal conductivity, can quickly absorb the heat of the casting, shorten the solidification time, and at the same time, the copper alloy has good mechanical strength and can withstand the thermal stress impact during the casting process; This movable chill is provided with longitudinal vent holes and transverse vent holes to enhance the gas diffusion ability, assist in heat dissipation, accelerate local cooling, relieve local thermal stress, and reduce the risk of cracks; This movable chill is provided with positioning holes and two threaded holes to ensure the accurate mating position of this movable chill with the sand core and shell core, and is convenient and quick to disassemble and assemble, ensuring the convenience and reusability of this movable chill. Brief Description of the Drawings

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings.

[0015] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of another angle of the present invention; Figure 3 For the present invention Figure 2 It is a schematic diagram of another angle; Figure 4 For the present invention Figure 3 It is a schematic diagram of another angle of the present invention; Figure 5 For the present invention Figure 1 It is a front view of the present invention; Figure 6 For the present invention Figure 1 It is a side view of the present invention.

[0016] Description of the Reference Numerals: 1. Chill body; 2. Working inclined surface; 3. Rib groove; 4. Positioning hole; 5. Exhaust groove; 6. Longitudinal vent hole; 7. Threaded hole; 8. Transverse vent hole. Detailed Embodiment

[0017] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will further introduce the present invention in detail in conjunction with the drawings.

[0018] The present invention provides a movable chill for aluminum alloy permanent mold casting as Figures 1 to 6 shown, including: Chill body 1 is made of a material with a thermal conductivity coefficient ≥ 200 W / (m·K). One end of the chill body 1 is provided with a transverse vent hole 8 and two threaded holes 7. The other end of the chill body 1 is provided with a working inclined surface 2 that is flush with the inclined surface of the shell core. The inclined surface is flush with the inclined surface of the shell core, forming a conformal contact interface to ensure uniform cooling of the flange surface and driving sequential solidification of the surrounding area through local rapid solidification. Multiple rib grooves 3 are provided on the working inclined surface 2. Exhaust grooves 5 are provided on both the upper and lower sides of the chill body 1. A positioning hole 4 and a longitudinal vent hole 6 are provided on the upper side of the chill body 1.

[0019] The chill body 1 is machined from a copper alloy material with high thermal conductivity. The copper alloy has high thermal conductivity, can quickly absorb the heat of the casting, shorten the solidification time, and at the same time, the copper alloy has good mechanical strength and can withstand the thermal stress impact during the casting process. The chill body 1 can also be made of other materials with a thermal conductivity coefficient ≥ 200 W / (m·K).

[0020] The number of rib grooves 3 is set to seventeen. The rib grooves 3 are parallel to the working inclined surface 2, and the interval between adjacent two rib grooves 3 is 1 mm. The rib grooves 3 increase the effective cooling area by more than 40%. Combined with the high thermal conductivity characteristics of the copper alloy, it accelerates the directional solidification of 1 / 3 area of the flange surface. The rib grooves 3 form a gap channel with the core, synchronously discharging the cavity gas and the gas precipitated during the solidification process, avoiding the defect of gas shrinkage holes.

[0021] The exhaust grooves 5 are provided along the length direction of the chill body 1. The number of exhaust grooves 5 is set to three. Two of the exhaust grooves 5 are provided on the upper side of the chill body 1, and the remaining one exhaust groove 5 is provided on the lower side of the chill body 1. The surface radiation heat dissipation and the internal convective heat dissipation of the groove body cooperate to reduce the thermal stress concentration.

[0022] The depth of the exhaust groove 5 is 0.5 mm. The exhaust groove 5 communicates with the corresponding rib groove 3. The combination of the exhaust groove 5 and the rib groove 3 not only enhances the exhaust effect, but also accelerates the local cooling by increasing the heat dissipation area, improving the density of the casting.

[0023] The upper end ports of the positioning hole 4 and the longitudinal vent hole 6 are located between the two exhaust grooves 5 on the upper side of the chill body 1. The positioning hole 4 and the longitudinal vent hole 6 both penetrate the upper and lower sides of the chill body 1. The setting of the positioning hole 4 realizes the precise alignment of this movable block type chill in the mold, ensures the accurate matching position of the chill with the core and the shell core, effectively controls the cooling area, and avoids uneven cooling caused by misalignment. The longitudinal vent hole 6 cooperates with the directional cooling of the chill, can relieve the local thermal stress, reduce the crack risk, and at the same time optimize the feeding path.

[0024] The horizontal through-exhaust hole 8 is opened in the middle of the side of the chill body 1 away from the working inclined surface 2. The horizontal through-exhaust hole 8 communicates with the vertical through-exhaust hole 6. The two threaded holes 7 are symmetrically distributed in front of and behind the horizontal through-exhaust hole 8; The horizontal through-exhaust hole 8 cooperates with the directional cooling of the chill to relieve local thermal stress, reduce the risk of cracks, and optimize the feeding path at the same time; the setting of the threaded holes 7 enables non-destructive disassembly, and the number of repeated uses can reach more than 50 times, improving the service life compared with the traditional knocking disassembly.

[0025] The surface of the chill body 1 is sprayed with a graphite-based refractory coating to prevent the copper alloy from adhering to the casting.

[0026] In the present invention, the chill body 1 is made of a copper alloy material with a high thermal conductivity coefficient. The copper alloy has high thermal conductivity, can quickly absorb the heat of the casting, shorten the solidification time, and at the same time the copper alloy has good mechanical strength and can withstand the thermal stress impact during the casting process; The front part of the chill body 1 is precisely fitted with the core. The working inclined surface 2 on the chill body 1 is flush with the inclined surface of the shell core, forming a conformal contact interface, ensuring uniform cooling of the flange surface, and driving the sequential solidification of the surrounding area through local rapid solidification. There are seventeen rib grooves 3 on the working inclined surface 2. The rib grooves 3 increase the effective cooling area by more than 40%. Combined with the high thermal conductivity characteristics of the copper alloy, the directional solidification of 1 / 3 of the flange surface is accelerated; Exhaust grooves 5 are opened on the upper and lower surfaces of the chill body 1. The exhaust grooves 5 and the rib grooves 3 form a complementary exhaust network, which not only enhances the exhaust effect, but also accelerates local cooling by increasing the heat dissipation area, improving the density of the casting; The vertical through-exhaust hole 6 and the horizontal through-exhaust hole 8 on the chill body 1 form a cross-exhaust network, enhancing the gas diffusion ability, assisting heat dissipation at the same time, accelerating local cooling, relieving local thermal stress, reducing the risk of cracks, and optimizing the feeding path; The setting of the positioning holes 4 on the chill body 1 enables the precise alignment of this loose-piece chill in the mold, ensuring the accurate matching position of the chill with the core and the shell core, effectively controlling the cooling area, and avoiding uneven cooling caused by misalignment; The setting of the two threaded holes 7 on the chill body 1 enables non-destructive disassembly, and the number of repeated uses can reach more than 50 times, improving the service life compared with the traditional knocking disassembly.

[0027] Only some exemplary embodiments of the present invention have been described by way of illustration. Undoubtedly, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A movable block chiller for aluminum alloy metal mold casting, characterized in that: include: A cold iron body (1), the cold iron body (1) being made of a material having a thermal conductivity coefficient of ≥200 W / (m·K), one end of the cold iron body (1) being provided with a transverse exhaust hole (8) and two threaded holes (7), the other end of the cold iron body (1) being provided with a working inclined surface (2) flush with the shell core inclined surface, the working inclined surface (2) being provided with a plurality of rib grooves (3), exhaust grooves (5) being provided on both upper and lower sides of the cold iron body (1), and a positioning hole (4) and a longitudinal exhaust hole (6) being provided on the upper side of the cold iron body (1).

2. The movable block chiller for aluminum alloy metal mold casting according to claim 1, characterized in that: The cold iron body (1) is made of a copper alloy material with a high thermal conductivity.

3. The movable block chiller for aluminum alloy metal mold casting according to claim 1, characterized in that: The number of the rib grooves (3) is seventeen, the rib grooves (3) are parallel to the working inclined surface (2), and the interval between two adjacent rib grooves (3) is 1 millimeter.

4. The movable block chiller for aluminum alloy metal mold casting according to claim 1, characterized in that: The exhaust groove (5) is opened along the length direction of the cold iron body (1), and the number of the exhaust grooves (5) is three, two of which are opened on the upper side of the cold iron body (1), and the remaining exhaust groove (5) is opened on the lower side of the cold iron body (1).

5. The movable block chiller for aluminum alloy metal mold casting according to claim 4, characterized in that: The depth of the exhaust groove (5) is 0.5 mm, and the exhaust groove (5) is connected to the corresponding rib groove (3).

6. The movable block chiller for aluminum alloy metal mold casting according to claim 4, characterized in that: The upper ends of the positioning hole (4) and the longitudinal exhaust hole (6) are located between the two exhaust grooves (5) on the upper side of the cold iron body (1), and the positioning hole (4) and the longitudinal exhaust hole (6) both penetrate the upper and lower sides of the cold iron body (1).

7. The movable block chiller for aluminum alloy metal mold casting according to claim 1, characterized in that: The transverse vent hole (8) is provided in the middle of a side of the cold iron body (1) away from the working inclined surface (2), the transverse vent hole (8) is connected with the longitudinal vent hole (6), and the two threaded holes (7) are symmetrically distributed on the front and rear sides of the transverse vent hole (8).

8. The movable block chiller for aluminum alloy metal mold casting according to claim 1, characterized in that: The surface of the chiller body (1) is sprayed with graphite-based refractory coating.

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