JP2005233571A - Heat treatment method and device for precipitation hardening type light alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat treatment method and a heat treatment device for precipitation hardening type light alloy capable of inhibiting thermal deformation. <P>SOLUTION: In this heat treatment of precipitation hardening type light alloy for improving the mechanical characteristic of a work W by performing solution treatment on the work W composed of the precipitation hardening type light alloy and then performing quenching treatment, at least the solution treatment is performed in such a state that the work W is buried in a fluidized bed 6 composed of granulated matters, and the flow of the granulated matters is stopped. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat treatment method and a heat treatment apparatus of precipitation-hardened light alloy.

  Tensile strength of the light alloy such as an aluminum alloy or a magnesium alloy conventionally, yield strength, heat treatment for further improving the mechanical properties such as elongation to (solution treatment), the conventional methods of over the atmosphere furnace tunnel furnace Instead, a heat treatment method is proposed that is performed in a fluidized bed adjusted to a predetermined temperature by direct blowing of hot air (see Patent Document 1).

This is to heat treat the cast product by causing the workpiece of the cast product made of light alloy to exist in a fluidized bed adjusted to a predetermined temperature by direct blowing of hot air. It can be made uniform, can be processed in a short time by increasing the solution temperature, can reduce the occurrence of blistering due to the effect of pressure by the granular material, and can be processed in a short time.
JP 2002-275567 A

  However, in the above conventional example, the air from the blower is heated to 700-800 ° C. hot air by the flame of the burner and blown into the fluidized bed furnace through the perforated pipe, so that the filled granular material flows by the heated air bubbles. Since the workpiece suspended by a hanger in the fluidized bed furnace is heat-treated, the heat-treated material is not constrained, and depending on the flow state of the granular material, a uniform temperature distribution cannot be obtained on the workpiece and heat is applied. deformed, it requires straightening in a later step.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a heat treatment method and heat treatment apparatus for a precipitation hardening light alloy capable of suppressing the occurrence of thermal deformation.

  The present invention is a heat treatment of a precipitation hardening light alloy that improves the mechanical properties of the workpiece by solution treatment of a workpiece made of a precipitation hardening light alloy and then quenching, at least the solution treatment. wherein the work to be performed in a state where the stopping flow of buried allowed and granulate in fluidized bed consisting of granular material.

  Therefore, in the present invention, precipitation hardening the workpiece solution treatment consisting of light alloy, then in the heat treatment to perform the quenching treatment, and granules is embedded at least the solution treatment in a fluidized bed consisting of granular material the work Therefore, the workpiece, which is the material to be processed, is fixed by the granular material whose flow has been stopped, the occurrence of thermal deformation can be suppressed, and distortion correction is not required in the subsequent process.

  It will be described below based on a heat treatment method and heat treatment apparatus precipitation hardened light alloy of the present invention to the embodiments.

(First embodiment)
FIG. 1 is a cross-sectional view showing a first embodiment of a precipitation hardening light alloy heat treatment apparatus to which the present invention is applied. In FIG. 1, a precipitation hardening light alloy heat treatment apparatus 1 includes a heating tank 2 formed in a lower layer and a quenching tank 3 formed in an upper layer, and the heating tank 2 and the quenching tank 3 can be opened and closed. Thus, the communication state or the shielding state can be obtained.

  The heating tank 2 is formed in the lower layer of the partition plate 4, and is divided by a porous plate 5 having a large number of nozzles 5 </ b> A for blowing hot air on the bottom side, whereby a fluidized bed 6 in which particulate matter is accumulated above the porous plate 5. forming a, the perforated plate 5 the lower space 7 is configured to supply hot air generated by the hot air generator 8.

  Granules for forming the fluidized bed 6 has a shape close to a spherical or spherical in order to stabilize the air permeability. Therefore, in the supply of the steady flow conditions of the hot air, particulate matter by hot air supplied from the nozzle. 5A granules and distributed by way of the clearance of particulate matter between without a fluidized state in the fluidized bed 6 The workpiece W embedded in the granular material can be heated. In the supply of the at increasing state of hot air, particulates becomes fluidized state in the fluidized layer 6, thereby enabling extraction from the burying operation into granules of the workpiece W and particulates within. Embedment of the workpiece W in the fluidized bed 6, support in the fluidized bed 6, and removal are performed by raising and lowering the hanger 9 of the transport device that supports the workpiece W.

  The hot air generator 8 is configured to be able to supply hot air to the space 7 below the perforated plate 5 by heating the air from the blower 10 with a burner (not shown), and by adjusting the amount of air supplied from the blower 10. , it can be supplied by adjusting the flow rate of the hot air. The temperature of the fluidized layer 6 is measured by the thermocouple 12A, the controller 11 the target combustion temperature of the burner of the hot air generator 8 so as to be furnace temperature always 530-550 ° C. in the range of 700 degrees to 800 degrees Celsius to adjust controlled by. As the target combustion temperature of the burner, the temperature of the hot air is measured by the thermocouple 12B, and the burner of the hot air generator 8 is adjusted by the controller 11. Further, the air volume of hot air is performed by controlling the supply flow rate of the blower 10 by the controller 11.

  The partition plate 4, shown with the fixed wall 4A that is fixed annularly along the inner wall surface of the heating tank 2, the movable wall 4B mounted to the movable state to the fixed wall 4A, and a 4C, movable wall 4B, the 4C by moving the operating position as the chain line shown by opening and closing the actuator 4D from communication with, it is made possible to shield state to shield between the heating chamber 2 and the quench tank 3. In the shielded state, the end of the drain pipe 13 that discharges the cooling medium flowing on the partition plate 4 to be described later to the outside of the quenching tank 3 is configured to open to the inner wall surface of the quenching tank 3. The drain pipe 13 includes an open / close valve 14 and communicates with the drain tank 15.

  The quenching bath 3 is provided by arranging a plurality of cooling medium injector 20 which is exposed from the wall surface in the circumferential direction at equal intervals. A plurality of cooling medium injection device 20 is connected to the coolant supply device 22 through the inlet conduit 21. The cooling medium supply device 22 can supply cooling air or cooling water to the cooling medium injection device 20, and the cooling medium injection device 20 injects the cooling medium to the cooling medium injection device 20 according to a command from the controller 11. is operable mist of cooling air or cooling water was injected into the workpiece W.

  It will be described below the heat treatment method according to the heat treatment apparatus 1 of the precipitation hardened light alloy having the above structure. In the heat treatment method of the precipitation hardened light alloy, first Si contained as an alloying element to the workpiece W, solution treatment to α phase by heating the Mg and Cu to the solubility limit temperature (solution treatment temperature) a step, and a quenching step of precipitating as α solid solution by quenching the workpiece W from its state. Then, if necessary aging treatment is performed on the workpiece W.

  First, in a state where the partition plate 4 is opened, the hot air generator 8 and the blower 10 are operated to supply hot air heated to 700 to 800 degrees Celsius by a burner to the heating tank 2, and a large number of nozzles 5 </ b> A of the perforated plate 5. to be supplied to the fluidized bed 6 from. The hot air to be supplied is supplied with hot air with an increased flow rate of air supplied from the blower 10 so that the particulate matter in the fluidized bed 6 flows. The granular material is heated by hot air and maintained at the solution temperature.

  Next, as shown in FIG. 2, the hanger 9 of the conveying device that holds the workpiece W is lowered, and the held workpiece W is embedded in the fluidized bed 6. Hangers 9 and the workpiece W, since the particulates are fluidized by hot air, can be embedded within a gradually granules.

  Next, switching the air flow rate supplied from the blower 10 to the small capacity of the steady state. The steady state hot air stops the flow of the granular material, and the hot air flows from the lower part to the upper part of the granular material. The embedded work W is heated with the granular material and the hot air, and rapidly rises to the solution temperature. temperature of the cell. For granules which has a shape close to a sphere or a sphere, the air permeability is stable, not fluidized. Solution treatment duration is performed in this state. Since the workpiece W is granules is not fluidized, the movement is prevented by the granular material, the workpiece W is fixed. Temperature of particulates and the workpiece W are solution temperature, for example, it is maintained at a temperature of 530-550 degrees Celsius.

  After the solution treatment time has elapsed, the amount of air supplied from the blower 10 is increased again, the particulate matter is brought into a fluidized state, the hanger 9 of the conveying device is raised, the workpiece W is taken out of the fluidized bed, and moved to the quenching tank 3. Since the particulate matter in the fluidized bed 6 is in a fluidized state due to the increased amount of hot air, the workpiece W and the hanger 9 can be easily taken out from the fluidized bed 6.

  Thereafter, the partition plate 4 is operated by the opening / closing actuator 4D, and the movable walls 4B and 4C are shielded to shut off the quenching tank 3 and the heating tank 2, and the supply flow rate from the blower 10 is heated to a steady state. The fluidized state of the granular material in the fluidized bed 6 of the tank 2 is stopped.

  In the quenching tank 3, the refrigerant supply device 22 is operated to supply a refrigerant made of cooling air or water to the refrigerant injection device 20, and the refrigerant is supplied from the refrigerant injection device 20 toward the workpiece W in a mist shape made of cooling air or water droplets. It injected, the hardening treatment by quenching the workpiece W. A coolant such as cooling water that has flowed down from the work W flows on the partition plate 4, flows on the upper surface of the fixed wall 4 </ b> A, and is discharged to the drain tank 15 via the drain pipe 13. When the workpiece W is cooled to a predetermined temperature by the quenching process, the operation of the refrigerant supply device 22 is stopped, and the injection of the mist-like refrigerant composed of cooling air or water droplets from the refrigerant injection device 20 is stopped. Quenching the treated workpiece W is taken out to the third outer heating tank raises the hanger 9, is conveyed to the next step.

  Then, for the next workpiece W, the partition plate 4 is opened, the next workpiece W is turned by hangers 9, solution heat treatment step and the quenching step are sequentially performed in the same manner.

  In the present embodiment, the following effects can be achieved.

  (A) precipitation processes hardening light solution the work W made of an alloy, then in the heat treatment to perform the quenching treatment, and granules is embedded at least the solution treatment in the fluidized bed 6 consisting of granules the workpiece W Therefore, the workpiece W, which is the material to be processed, is fixed by the granular material whose flow has been stopped, the occurrence of thermal deformation can be suppressed, and distortion correction is not required in the subsequent process.

  (B) granules of the fluidized layer 6, and the like to increase the hot air supply pressure or hot air supply amount of the hot air generator 8, since the time of turn-on and removal of the workpiece W to flow, is embedded in the workpiece W in the particulate material within the or it can be easily removed from the granules.

  (C) is interposed partition plate 4 as shielding means on top of the heating tank 2 for solution treatment adjacent quenching chamber 3 for performing hardening treatment on the workpiece W arranged, solution treatment after completion of the work W the move to the quench tank 3 for quenching the partition plate 4 as a shielding state, reduces the travel time of the workpiece W to be heat-treated, quenching treatment without decreasing the workpiece temperature after solution treatment but it can be performed, thereby improving the material properties of the workpiece W.

(Second Embodiment)
4 and 5 show a second embodiment of a precipitation hardening light alloy heat treatment apparatus to which the present invention is applied, FIG. 4 is a sectional view of a solution treatment process by the heat treatment apparatus, and FIG. 5 is a quenching process by the heat treatment apparatus. It is sectional drawing of a process. In the present embodiment, the function of a quenching tank is provided by adding a particulate collection / return function and a refrigerant injection function to the heating tank. The same devices as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted or simplified.

  In FIG. 4, the heating tank 2 includes a tapered bottom portion 2A inclined in an inverted conical shape, and the stored particulate matter can be collected in the collection tank 31 via the discharge pipe 30 connected to the center of the bottom portion 2A. It constitutes the, in the middle portion of the discharge line 30 is provided with a recovery pump 32 operated by drive motor 32A. The recovery tank 31, the hot air from the hot air generator 8 is capable of introducing structure in the vicinity of the bottom at inlet valve 33 open, the collected particulates are fluidized by hot air introduced and driven by way of the return line 34 motor it is configured such that can be returned into the heating tank 2 by a pump 35 back operated by 35A.

  The heating tank 2, a perforated pipe 36 constituted by passing rack in the middle portion of the heating tank 2, by supplying into the perforated pipe 36 hot air from the hot air generator 8 through a supply valve 37, perforated pipes 36 so that then blowing hot air from the plurality of nozzle holes 36A.

  Further, the wall surface of the heating tank 2 is provided by arranging a plurality of cooling medium injector 20 which is exposed from the wall surface in the circumferential direction at equal intervals, as in the first embodiment, cooling air or cooling water (not shown) It is configured to be supplied from the coolant supply device 22. In addition, in order to collect the jetted cooling water mist, the drain pipe 15 is branched to the drain pipe 13 and the open / close valve 14 formed in the middle of the drain pipe 13 is connected to the drain tank 15. It is communicated.

  A heat treatment method using the precipitation hardening light alloy heat treatment apparatus 1A having the above-described configuration will be described below. FIG. 4 shows a state at the time of solution treatment, in which granular materials are accumulated in the heating tank 2, and hot air heated by a burner to 700 to 800 degrees Celsius by operating the hot air generator 8 and the blower 10 is used. It is supplied to the porous pipe 36, supplied into the heating tank 2 from a number of nozzles 36A of the porous pipe 36. The hot air to be supplied is supplied with hot air having an increased flow rate of air supplied from the blower 10 so that the granular material is allowed to flow. The granular material is heated by hot air and maintained at the solution temperature.

  Subsequently, the hanger 9 of the conveying apparatus holding the workpiece W is lowered, and the held workpiece W is embedded in the fluidized particulate matter. The hangers 9 and the work W can be gradually embedded in the granular material because the granular material is flowing with hot air.

  Next, the air flow rate supplied from the blower 10 is switched to a steady state. The steady state hot air stops the flow of the granular material, and the hot air flows from the lower part to the upper part of the granular material. The embedded work W is heated with the granular material and the hot air, and rapidly rises to the solution temperature. temperature of the cell. For granules which has a shape close to a sphere or a sphere, the air permeability is stable, not fluidized. Solution treatment duration is performed in this state. Since the workpiece W is granules is not fluidized, the movement is prevented by the granular material, the workpiece W is fixed. Temperature of particulates and the workpiece W are solution temperature, for example, it is maintained at a temperature of 530-550 degrees Celsius.

  After lapse of the solution treatment time, the recovery pump 32 is actuated to recover particulate matter in the recovery tank 31, the collecting pump 32 at the time the recovery is completed stopped, hot air to the perforated pipe 36 by closing the supply valve 37 to stop the supply of. Then, hot air from the hot air generator 8 is supplied to the recovery tank 31 with the introduction valve 33 opened, and the particulate matter in the recovery tank 31 is kept warm.

  Then, as shown in FIG. 5, in the heating tank 2 the workpiece W to be processed material is supported on the hanger 9, a refrigerant consisting of cooling air or water by operating the coolant supply unit 22 to the refrigerant injection apparatus 20 Then, the refrigerant is injected from the refrigerant injection device 20 toward the workpiece W in the form of a mist made of cooling air or water droplets, and the workpiece W is quenched to quench. Refrigerant such as cooling water flowing down from the work W is discharged to the drain tank 15 via the drain pipe 13 branched from the discharge pipe 30 of the bottom 2A. When the workpiece W is cooled to a predetermined temperature by the quenching process, the operation of the refrigerant supply device 22 is stopped, and the injection of the mist-like refrigerant composed of cooling air or water droplets from the refrigerant injection device 20 is stopped. Quenching the treated workpiece W is taken out to the outside the heating tank 2 raises the hanger 9, it is conveyed to the next step.

  Next, for the next workpiece W, the hot air supplied to the recovery tank 31 from the hot air generator 8 is increased to fluidize the particulate matter, and the return pump 35 is operated to remove the particulate matter in the recovery tank 31. back into the heating tank 2. When the return of the particulate matter in the recovery tank 31 to the heating tank 2 is completed, the return pump 35 is stopped, the hot air from the hot air generator 8 is closed, the introduction valve 33 is closed, the supply valve 37 is opened, and the porous pipe 36 is opened. It is supplied to the supply into the heating chamber 2 from a number of nozzles 36A of the porous pipe 36. Hot air supply supplies hot air to the air flow rate supplied with the increase than that blower 10, a state for flowing particulates. The granular material is heated by hot air and maintained at the solution temperature.

  Thereafter, the next workpiece W is loaded by the hanger 9 by the same procedure, and the solution treatment process and the quenching process are sequentially performed in the same manner.

  In the present embodiment, in addition to the effects (a) and (b) in the first embodiment, the following effects can be achieved.

  (D) The heating tank 2 for performing the solution treatment is provided with the particulate supply / discharge means 30 to 35 for supplying and discharging the particulate matter and the refrigerant injection means 20 for injecting the refrigerant, and the particulate supply / discharge means after the solution treatment is completed. discharging the particulate material in the heating chamber 2 by 30 to 35, it is possible to perform the hardening process the workpiece W by ejecting coolant by the coolant injection means 20, in the heating tank 2 without moving the workpiece W, Integrated treatment from solution treatment to quenching is possible, and heat treatment can be performed efficiently.

Sectional view of a heat treatment apparatus precipitation hardened light alloy of an embodiment of the present invention. Also cross-sectional view at the time of solution treatment by the heat treatment apparatus. Also cross-sectional view of the quenching treatment by the heat treatment apparatus. Sectional view during the solution treatment of the heat treatment apparatus of precipitation hardened light alloy showing a second embodiment of the present invention. Also cross-sectional view of the quenching treatment by the heat treatment apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A Heat processing apparatus 2 Heating tank 3 Quenching tank 4 Partition plate as a partition means 5 Porous plate 6 Fluidized bed 7 Space 8 Hot air generator 9 Hanger 10 Blower 11 Controller 20 Refrigerant injection apparatus 22 Refrigerant supply apparatus

Claims (8)

In the heat treatment method of the precipitation hardening light alloy, which improves the mechanical properties of the work by subjecting the work consisting of the precipitation hardening light alloy to solution treatment and then quenching,
A heat treatment method for a precipitation hardening light alloy, wherein the solution treatment is performed in a state where the work is embedded in a fluidized bed made of a granular material and the flow of the granular material is stopped.   The precipitation-hardening light alloy heat treatment method according to claim 1, wherein the granular material in the fluidized bed is fluidized at the time of loading and unloading a workpiece.   The heating bath for performing the solution treatment includes a quenching bath for quenching the workpiece by interposing a shielding means on the upper portion thereof, moving the workpiece after the solution treatment to the quenching bath, and quenching the shielding means in a shielding state. heat treatment method of the precipitation hardened light alloy according to claim 1 or claim 2, characterized in that process. The heating tank for performing the solution treatment includes a granular material supply / discharge means for supplying and discharging the granular material and a refrigerant injection means for injecting a refrigerant.
The particulate matter in a heating tank is discharged | emitted by a granular material supply discharge means after completion | finish of a solution treatment, a refrigerant | coolant is injected by a refrigerant | coolant injection means, and a hardening process is given to the workpiece | work. Heat treatment method for precipitation hardening type light alloys. It is a heat treatment apparatus for precipitation hardening light alloy that improves the mechanical properties of the work by subjecting the work consisting of precipitation hardening light alloy to solution treatment and then quenching,
A heating tank that embeds and stores the charged workpiece in a granular material;
Hot air generating means for supplying hot air to the heating tank,
The heat treatment apparatus for precipitation hardening light alloy, wherein the solution solution treatment of the workpiece is performed in a state where the flow rate of the granular material is stopped by reducing the flow rate supplied from the hot air generator.   6. The heat treatment apparatus for a precipitation hardening light alloy according to claim 5, wherein the hot air supply pressure or the hot air supply amount of the hot air generator is increased so as to cause the granular material to flow when the workpiece is inserted and taken out.   The heating bath is arranged adjacent with intervening partition means thereon, characterized in that it comprises a quenching tank for quenching treatment by spraying a coolant to the work after the solution treatment at a heating bath according to claim 5 or The heat processing apparatus of the precipitation hardening type light alloy of Claim 6.   The heating tank includes a granular material supply / discharge means for supplying and discharging the granular material, and a refrigerant injection means for injecting a refrigerant, and the granular material is recovered from the heating tank by the granular material supply / discharge means after the solution solution treatment of the workpiece. The heat treatment apparatus for precipitation hardening light alloy according to claim 5 or 6, wherein the workpiece is quenched by quenching with coolant injection by coolant injection means.

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