JP2008144215A - Heat treatment device and heat treatment method for aluminum alloy material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat treatment device and a heat treatment method capable of suppressing cooling strain. <P>SOLUTION: In the heat treatment device and heat treatment method for an aluminum alloy material where a thin casting (workpiece) W made of an aluminum alloy is heated-up to the vicinity of an eutectic point, and is held at the temperature for a prescribed time, and thereafter, cooling media are sprayed from a plurality of nozzles 5 to the casting W, thus solution treatment is performed. The device is provided with: a plurality of the spray nozzles 5 confronted with the workpiece W and spraying the cooling media to the workpiece W; and an exhaust duct 6 opening so as to face to the surface of the workpiece different from the spraying parts of the cooling media in the surface of the work, and the workpiece W is cooled by the fluidization of the cooling media going toward the opening of the exhaust duct 6 along the surface of the workpiece from the spray nozzles 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a heat treatment apparatus and a heat treatment method for an aluminum alloy material, and more particularly to a heat treatment apparatus and a heat treatment method for an aluminum alloy material suitable for thin-walled parts.

  Conventionally, a cast casting of an Al-Si based aluminum alloy is rapidly heated to a temperature just below the eutectic point, and after reaching the vicinity of the eutectic point, it is subjected to solution treatment by rapid cooling, and then various aging There is known a heat treatment method for an aluminum alloy material that is subjected to a heat treatment (see Patent Document 1).

This is because a first step of casting an aluminum alloy material in a casting machine and a hot eutectic gas in which the cast piston casting product is circulated from the heat generator into the eutectic point (530 ° C.). ) The second step of rapidly heating up to about 520 ° C. in the vicinity and the piston casting product that has reached a high temperature, while controlling the ambient temperature to be uniform by a cooling fan device in the holding chamber, for about 3 minutes, And a third step in which each of the piston castings is maintained at a temperature of about 520 ° C. Then, a fourth step in which the piston casting product is introduced into the cooling water tank from the holding chamber and rapidly cooled, and then, the rapidly cooled piston casting product is introduced into the aging furnace for a predetermined temperature and time. A fifth step of performing an aging treatment is provided, and heat treatment is thereby performed to ensure sufficient hardness of the aluminum alloy casting while shortening the treatment time and suppressing energy consumption.
JP-A-2005-133103

  By the way, when the heat treatment method of the above-described conventional example is applied to a thin aluminum alloy material, the workpiece is cooled rapidly by being charged into the cooling water tank from the holding chamber in the fourth step. There is a concern that distortion occurs, and in particular, when the shape of the component is complicated, a difference occurs in the cooling rate due to the difference in mass of the parts of the component, and the cooling distortion becomes significant. This cooling distortion is also expected to occur in the same manner when the component shape is complicated even in the case of rapid cooling by blowing cooling air instead of the cooling water tank as a cooling means.

  Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide a heat treatment apparatus and a heat treatment method for an aluminum alloy material capable of suppressing cooling distortion.

  The present invention raises the temperature of a thin cast product made of an aluminum alloy to the vicinity of the eutectic point, holds that temperature for a predetermined time, and then rapidly cools the cast product by spraying a cooling medium from a plurality of nozzles. A heat treatment apparatus and a heat treatment method for an aluminum alloy material for performing a solution treatment, a plurality of spray nozzles for spraying a cooling medium on the work so as to face the work, and a work surface different from a spraying position of the cooling medium on the work surface And an exhaust duct that opens to the outside and communicates with the outside of the cooling booth. The work is cooled by the flow of the cooling medium from the spray nozzle toward the opening of the exhaust duct along the work surface.

  Therefore, according to the present invention, a plurality of spray nozzles that face the work in the cooling booth and spray a cooling medium onto the work, and open to face the work surface different from the spraying position of the cooling medium on the work surface, and the cooling booth An exhaust duct communicated to the outside is provided, and the work is cooled by the flow of the cooling medium from the spray nozzle toward the opening of the exhaust duct along the work surface. That is, the cooling medium discharged from the spray nozzle flows on the surface of the work along the flow of the cooling medium flowing from the spray position to the work toward the opening of the exhaust duct, and is sequentially discharged from the exhaust duct. For this reason, the sprayed cooling medium does not rebound from the work surface and becomes a flow resistance against the subsequently blown cooling medium, and it flows on the work surface without losing the flow velocity, improving the work cooling efficiency. Can be made.

  Hereinafter, a heat treatment apparatus and a heat treatment method for an aluminum alloy material according to the present invention will be described based on an embodiment. 1 to 6 show a first embodiment of a heat treatment apparatus and heat treatment method for an aluminum alloy material to which the present invention is applied, FIG. 1 is a process diagram showing a heat treatment process of the present embodiment, and FIG. 2 is a rapid cooling of the heat treatment process. FIG. 3 is a sectional view and a side view of an automobile door beam as a workpiece, FIG. 4 is a sectional view of a cooling booth of the first embodiment in the rapid cooling process, and FIG. 5 is a sectional view of the second embodiment in the rapid cooling process. FIG. 6 is a sectional view of the cooling booth of the third embodiment in the rapid cooling process.

  In FIG. 1, the aluminum alloy material is heat treated by casting the aluminum alloy material in a casting machine (S1), taking out the thin cast product from the casting mold after completion of solidification, removing the gate and burrs, and finishing (S2). It is put into a heating furnace and heated to, for example, about 520 ° C. near the eutectic point by the high-temperature gas circulating inside, and in that state, for example, is held for 60 to 90 minutes (S3).

  Subsequently, the thin cast product is put into a cooling booth from the storage room by a transporter in a fixed posture, and is rapidly cooled here (S4). Thereafter, the rapidly cooled thin-walled cast product is put into an aging furnace, where, for example, an aging treatment is performed at a temperature of about 200 ° C. for about 1.5 hours (S5). A heat treatment method for an aluminum alloy material comprising these solution treatment and aging treatment is a generally performed process.

  In the heat treatment method of the present embodiment, in the rapid cooling step (S4), the thin cast product W, which is a workpiece, is cooled with a cooling medium at a cooling rate of 300 to 400 ° C./min by the cooling booth 1 shown in FIGS. It is characterized by cooling with some cooling air.

  Here, the thin cast product W which is a workpiece | work is demonstrated with reference to FIG. A thin cast product W shown in FIG. 3 shows a door beam (guard bar) equipped inside the door of an automobile in order to suppress the intrusion of the door panel into the interior and to secure a living space for the occupant at the time of a collision from the side of the vehicle. For this door beam, a pipe material made of high-strength steel is usually used. However, a thin-walled cast product made of an aluminum alloy may be used because of the light weight of the vehicle and the high degree of freedom of the cross-sectional shape. The door beam shown in FIG. 3 is formed by a thin plate (planar portion W1) having a thickness of about 2 mm formed in a uniform cross-sectional shape from the front end F to the rear end R, and toward the outside of the vehicle in the central portion in the vertical direction. The thin plate is protruded with a slight curve, and includes a central thick portion W2 formed at the protruding tip portion and a lower thick portion W3 formed from the thick plate to the inside and outside of the vehicle on the lower side in the vertical direction. Yes. These thick portions W2 and W3 and the curved portion W4 formed on the thick plate are for improving the bending rigidity of the door beam. Further, a partial projection W5 is formed on the outer side of the upper side of the thin plate.

  The cooling booth 1 shown in FIG. 2 and FIG. 4 is arranged downstream of the heating furnace 2 and the greenhouse 3 and is conveyed with the work conveying means 4 arranged in the center of the booth 1 vertically. A plurality of nozzle groups 5 that blow cooling air as a cooling medium to the workpiece W, and a suction that is arranged at a position facing the nozzle group 5 across the workpiece W and sucks and discharges air in the booth 1 An exhaust device 6, a blower 8 that supplies cooling air to each nozzle group 5 via a duct 7, an adjustment valve 9 that adjusts the amount of cooling air injected from the nozzle group 5, and a plurality of temperatures for measuring the temperature of the workpiece W A temperature sensor 10 and a controller 11 that adjusts the opening degree of the regulating valve 9 and the blower amount of the blower 8 based on a temperature signal from the temperature sensor 10 are provided. The plurality of temperature sensors 10 are representatively illustrated only partially, but are arranged so as to be able to measure the temperature of each part of the workpiece W to be conveyed over the entire range in the conveyance direction of the workpiece W. It is what.

  In the cooling booth 1 shown in FIG. 2, the nozzle group 5 and the suction / exhaust device 6 facing each other across the workpiece W are arranged in an alternating manner from the upstream region to the downstream region of the cooling booth 1. They are arranged in three places.

  A plurality of nozzle groups 5 are arranged for each region from the upstream region to the downstream region of the cooling booth 1 and are arranged over the upper and lower regions of the cooling booth 1. And while blowing cooling air to the workpiece | work W simultaneously from the nozzle group 5 of one side with respect to the workpiece | work W conveyed in the center of the cooling booth 1, inside the booth 1 by the suction exhaust apparatus 6 located in the other side of the workpiece | work W By sucking and discharging air, the air that is the cooling medium discharged from the nozzle group 5 is circulated to the other surface of the workpiece W to cool the other surface of the workpiece W, and then the suction exhaust device 6 The work W is cooled by discharging it from the booth 1 to the outside.

  As the workpiece W is moved downstream by the conveying means 4, the positions of the nozzle group 5 and the suction / exhaust device 6 that are operated change from side to side, so that the workpiece W is evenly cooled from both sides, and the position depends on the workpiece conveying position. The temperature is lowered to reach the target temperature. The temperature of the workpiece W itself is detected by the temperature sensor 10 arranged for each region and fed back to the controller 11.

  In the heat treatment method using the heat treatment apparatus for an aluminum alloy material having the above-described structure, the thin cast product W is cast (S1) in a casting machine, taken out from the casting mold after solidification is completed, and the pouring gate and burrs are removed by finishing (S2). The aluminum alloy material is put into the heating furnace 2 by a robot hand (not shown), and is rapidly heated to, for example, about 520 ° C. near the eutectic point by the hot gas circulating inside. Then, after being held for 60 to 90 minutes (S3), it is conveyed by the conveying means 4 from the thermal storage room 3 into the cooling booth 1 in a fixed posture and put in.

  In the cooling booth 1, the blowing of the cooling air from the nozzle group S arranged in the predetermined area on the charging side is temporarily stopped, and the blowing of the cooling air from the nozzle group L arranged in the rear stage area was performed. State. In a state where the workpiece W thrown in by the conveying means 4 partially enters the cooling booth 1, the blowout of the cooling air from the nozzle group S in the loading side region is kept stopped, and the entire workpiece W is cooled. From the time when the booth 1 is entered, the cooling air blowing from the nozzle group S in the input side area is resumed. The temporary stop of the blowing of the cooling air from the nozzle group S in the charging side region is performed every time the work W is thrown into the cooling booth 1, and the cooling by the cooling air blowing is performed on a part of the work W (conveying direction). It is made to start simultaneously from the whole workpiece W without starting from the front end side.

  The cooling air blown out from the nozzle group S arranged in the upstream area of the booth 1 is in contact with the workpiece W and then spreads along the workpiece W in the left-right direction and the up-down direction to cool the workpiece W from one side. At the same time, the air that faces the other surface of the workpiece W is discharged out of the booth 1 by the suction / exhaust device 6, so that the cooling air that is blown out from the nozzle group S and flows along the workpiece W is on the other surface side of the workpiece W. The workpiece W is cooled from the other surface by flowing around the other surface of the workpiece W. As described above, the cooling air flows along one surface of the workpiece W, flows around the workpiece W, and also flows along the other surface, so that the workpiece W is cooled in a substantially uniform temperature state.

  Therefore, the cooling air discharged from the nozzle group S bounces after contacting the workpiece W, does not become resistance to the cooling air blown later, and does not stay in the cooling booth 1, and from the surface side of the workpiece W. The cooling efficiency with respect to the workpiece W can be improved by being drawn toward the back surface and flowing on the workpiece surface without losing the flow velocity.

  As the work W is transported downstream by the transport means 4, the nozzle group L that blows cooling air to the work W and the suction / exhaust device 6 that discharges from the work side are updated downstream, and the other surface side While the cooling air blown out from the nozzle group L contacts the other surface of the workpiece W and flows in the vertical and horizontal directions along the workpiece surface, the air on one surface side is drawn by the suction exhaust device 6 on the surface side. By being discharged, the cooling air that is blown out from the nozzle group L on the other surface and flows along the workpiece W wraps around one surface of the workpiece W and flows along one surface of the workpiece W. Cool W from one side. In this way, the work W is circulated around the work W by the cooling air from the nozzle groups S and L arranged alternately and flows along the surface of the work W, and by the suction exhaust apparatus 6 arranged alternately. The workpiece W is cooled in a substantially uniform temperature state by the nozzle groups S and L and the suction / exhaust device 6 alternately on both surfaces.

  The temperature of the workpiece W is detected by the temperature sensor 10. Then, it is determined by the controller 11 whether or not the temperature has been lowered to a temperature corresponding to the transport position, and when the temperature is further lowered from the set temperature, the amount of air blown from the blower 8 is reduced, or When the opening of each regulating valve 9 is narrowed and the temperature drop is less than the set temperature, the air flow from the blower 8 is increased or the opening of each regulating valve 9 is opened and the temperature of the workpiece W is increased. Control to achieve the target temperature drop.

  Then, the workpiece W reaches the outlet of the cooling booth 1 and the workpiece W is carried out of the cooling booth 1. If the temperature at this time is lowered to about 50 ° C., the solution treatment has been completed, and the work W starts aging treatment in a subsequent process.

  In the heat treatment apparatus for aluminum alloy material of the second embodiment shown in FIG. 5, the nozzle group 5 for blowing cooling air and the suction exhaust apparatus 6 for discharging the air in the booth 1 are opposed to each other with the work W interposed therebetween. Instead, they are arranged on the same side with respect to the workpiece W.

  That is, in FIG. 5, on both sides of the workpiece W, a nozzle group 5 that blows out cooling air and a suction / exhaust device 6 are arranged in a positional relationship that these nozzle groups 5 surround. Therefore, the cooling air blown out from the nozzle group 5 can flow along the workpiece surface without bouncing after contacting the workpiece W, and then is separated from the workpiece surface by the suction exhaust device 6 and exhausted outside the booth 1. Is done.

  Thus, by arranging the nozzle group 5 and the suction / exhaust device 6 on each side of the workpiece W, the cooling air blown out from the nozzle group 5 flows along the workpiece surface, and then flows to the other workpiece W. Since it is discharged without going around, the cooling efficiency can be further improved.

  In this case, the nozzle group 5 is arranged with emphasis on the central portion of the workpiece W, the thick portion of the workpiece W, etc., where the temperature is difficult to decrease, and a plurality of suction exhaust devices 6 are arranged surrounding these nozzle groups. It is desirable.

  The aluminum alloy material heat treatment apparatus of the third embodiment shown in FIG. 6 is provided with an exhaust duct for discharging air at a local portion of the workpiece surface.

  That is, in FIG. 6, local exhaust ducts 6 </ b> A that are close to both sides of the thick part W <b> 2 of the workpiece W and that face the opening and communicate with the outside of the booth 1 are arranged. These exhaust ducts 6 </ b> A function to discharge air in the vicinity of the workpiece W when the pressure in the cooling booth 1 is increased by the cooling air blown out from the nozzle group 5. For this reason, when the product shape of the workpiece W is particularly complicated, the air is actively discharged from the corresponding portion by arranging the opening so that the opening faces the workpiece surface 30 where air is likely to stay. Surface cooling air can be drawn and discharged one after another. Accordingly, it is possible to prevent the stagnation of air on the workpiece surface and cool the workpiece W uniformly.

  In the embodiment shown in FIG. 6, the nozzle group 5 is arranged on one side of the workpiece W, and the suction exhaust device 6 (large exhaust duct) for exhausting the entire workpiece W is arranged on the other side of the workpiece W. 1 has a structure in which the pressure in 1 is difficult to rise. Therefore, these local exhaust ducts 6A are equipped with a suction fan 6B or an ejector 6C for sucking air from the inside of the cooling booth 1, so that the air on the workpiece surface is positively exhausted.

  In the heat treatment apparatus for an aluminum alloy material of the fourth embodiment shown in FIG. 7, a large number of blowout nozzles 5 and a large number of exhaust ducts 6 </ b> D are arranged evenly distributed on the respective wall surfaces of the cooling booth 1. The cooling air blown out from each blow-out nozzle 5 spreads in the vertical and horizontal directions of the work surface after flowing in contact with the work surface, flows along the work surface, and is discharged out of the cooling booth 1 from the exhaust duct 6D opened adjacent to each other. The Therefore, it is possible to prevent air from staying on the work surface.

  In this case, when the workpiece shape is complex, the workpiece W can be increased by increasing the air flow rate or flow velocity blown from the blowing nozzle 5 facing the thick-walled portion or the workpiece central portion that is difficult to cool, or by lowering the air temperature. Can be cooled uniformly. Moreover, the work W can be uniformly cooled also by arranging the arrangement density of the blow nozzles 5 high in a thick part that is difficult to be cooled or in the center of the work. Of course, when the exhaust duct 6D is equipped with a suction fan or an ejector that sucks air from the inside of the cooling booth 1, the air on the surface of the workpiece is positively forcedly exhausted, thereby further improving the cooling effect of the workpiece W. Can be increased.

  In the above-described embodiment, the cooling booth 1 is described as one that is continuously cooled by the cooling air blown from the nozzles 5 arranged on the side wall of the booth 1 while the workpiece W is conveyed by the conveying means 4. However, the work may be cooled by spraying cooling air from a spray nozzle arranged on the side wall of the cooling booth for a preset time after stopping the conveying means in the cooling booth.

  In the above embodiment, the thin cast part W to be heat treated has been described for the door beam. Although not shown, various reinforcing members (reinforce) and structural members made of an aluminum alloy material for automobiles, for example, suspension members are used. May be intended.

  Moreover, as shown in the figure, the workpiece W is not limited to one having a uniform cross-sectional shape. For example, a partially thick portion such as a mounting boss may be formed on the workpiece surface as necessary. Even if they are arranged in a scattered manner, the cooling air may be supplied toward these thick portions. In this case, it is desirable that the workpiece is stopped at the cooling position by the conveying device, or that each spray nozzle moves together with the conveying means.

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

  (A) The temperature of the thin cast product W made of an aluminum alloy is raised to the vicinity of the eutectic point, held at that temperature for a predetermined time, and then rapidly cooled by spraying a cooling medium from the plurality of nozzles 5 onto the cast product W. A heat treatment apparatus and a heat treatment method for an aluminum alloy material that performs a solution treatment by the above, a plurality of spray nozzles 5 that face the workpiece W and spray a coolant onto the workpiece W, and spray the coolant on the workpiece surface An exhaust duct 6 that opens to face the workpiece surface different from the location and communicates with the outside of the cooling booth 1, and flows by the flow of the cooling medium from the spray nozzle 5 toward the opening of the exhaust duct 6 along the workpiece surface. The workpiece W was cooled. Therefore, the cooling medium discharged from the spray nozzle 5 flows on the surface of the work along the flow of the cooling medium flowing from the sprayed portion to the work W toward the opening of the exhaust duct 6, and sequentially from the exhaust duct 6. Discharged. Therefore, the sprayed cooling medium does not rebound from the work surface and becomes a flow resistance against the subsequently blown cooling medium, and flows on the work surface without losing the flow velocity, thereby improving the cooling efficiency of the work W. Can be improved.

  (A) As shown in FIG. 4, the outlets of the plurality of spray nozzles 5 and the openings of the exhaust duct 6 are arranged at positions facing each other across the workpiece W, whereby one surface of the workpiece W Thus, the cooling medium can be caused to wrap around the other surface of the workpiece W, and the workpiece W can be uniformly and effectively cooled even in the spray nozzle 5 and the exhaust duct 6 with limited quantities.

  (C) As shown in FIG. 6, the exhaust duct includes a large exhaust duct 6 that exhausts the cooling medium present on one side of the work W as a whole, and a local surface with the opening adjacent to the local surface of the work W. By forming the local exhaust duct 6A that discharges the cooling medium from a smooth surface, the cooling medium in the portion 30 staying on the work surface can be effectively exhausted, and the generation of cooling distortion is suppressed and a uniform cooling effect is achieved. It can be demonstrated.

  (D) As shown in FIG. 5, the outlets of the plurality of spray nozzles 5 and the openings of the exhaust duct 6 face the workpiece W from the same direction, so that one surface of the workpiece W is opposite to the other. The work W can be efficiently and uniformly cooled without requiring the cooling medium to wrap around the surface.

  (E) As shown in FIG. 7, the spray nozzle 5 and the opening of the exhaust duct 6 </ b> D face the workpiece surface in an arrangement adjacent to each other, thereby cooling the spray sprayed from the spray nozzle 5. It is possible to stably obtain a flow that flows to the opening of the exhaust duct 6D along the surface of the medium work, and the flow rate and speed of the cooling medium from the spray nozzle 5, the temperature of the coolant, and the spray nozzle. By adjusting the arrangement density of 5 and the like, even the workpiece W not having a uniform mass can be cooled at a uniform cooling rate.

  (F) Since the suction ducts 6B and 6C for discharging the cooling medium in the cooling booth 1 to the outside of the cooling booth 1 are arranged in the exhaust ducts 6 and 6D, the cooling medium in the cooling booth 1 can be stably supplied. Since it can discharge | emit out of the booth 1, the flow of the cooling medium which goes to the exhaust ducts 6 and 6A from the spray nozzle 5 can be flowed stably and in large quantities along a workpiece | work surface, and cooling efficiency can be improved.

The schematic process drawing of the heat treatment method of the aluminum alloy material which shows one embodiment of the present invention. The top view which similarly shows the rapid cooling process of a heat treatment process. Sectional drawing and side view of the door beam of the motor vehicle as a workpiece | work. Sectional drawing of the cooling booth of 1st Example in a rapid cooling process. Sectional drawing of the cooling booth of 2nd Example in a rapid cooling process. Sectional drawing of the cooling booth of 3rd Example in a rapid cooling process. Sectional drawing of the cooling booth of 4th Example in a rapid cooling process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cooling booth 2 Heating furnace 3 Storage room 4 Conveying means 5 Nozzle 6, 6A Suction exhaust duct 8 Blower 9 Adjusting valve 10 Temperature sensor 11 Controller

Claims (9)

A thin cast product made of an aluminum alloy is heated to the vicinity of the eutectic point, held at that temperature for a predetermined time, and then rapidly cooled by spraying a cooling medium from a plurality of spray nozzles to the cast product in a cooling booth. It is a heat treatment method of an aluminum alloy material that performs solution treatment by
Exhaust air that opens to face the work surface different from the sprayed portion of the cooling medium on the work surface and communicates outside the cooling booth while blowing the cooling medium to the work surface from a plurality of spray nozzles arranged to face the work surface. A method for heat-treating an aluminum alloy material, comprising: discharging a cooling medium in a cooling booth from a duct to cool the work with a cooling medium that flows from a spray nozzle toward the opening of the exhaust duct along the work surface. The cooling medium spray point from the plurality of spray nozzles faces one surface of the work, and the opening of the exhaust duct faces the other surface of the work,
2. The aluminum alloy according to claim 1, wherein the cooling medium sprayed to the work from the spray nozzle circulates from one side of the work to the other of the work along the work surface and is discharged from an opening of the exhaust duct. Material heat treatment method.   The exhaust duct includes a large exhaust duct that exhausts the entire cooling medium existing on one side of the work, and a local exhaust duct that discharges the cooling medium from a local surface with an opening adjacent to the local surface of the work. The cooling medium formed around the workpiece and discharged around the work is discharged through the large exhaust duct, while the cooling medium at the local portion of the work surface is discharged through the local exhaust duct. A heat treatment method for an aluminum alloy material according to 1. A thin cast product made of an aluminum alloy is heated to the vicinity of the eutectic point, held at that temperature for a predetermined time, and then subjected to a solution treatment process by rapidly cooling the cast product by spraying a cooling medium from a plurality of nozzles. A heat treatment apparatus for aluminum alloy material,
A plurality of spray nozzles that face the work and spray a coolant onto the work;
An exhaust duct that opens to face the surface of the work different from the sprayed portion of the cooling medium on the work surface and communicates outside the cooling booth, and
A heat treatment apparatus for an aluminum alloy material, wherein the work is cooled by a cooling medium that flows from the spray nozzle along the work surface toward the opening of the exhaust duct.   5. The aluminum alloy material heat treatment apparatus according to claim 4, wherein the outlets of the plurality of spray nozzles and the openings of the exhaust duct are disposed at positions facing each other with the workpiece interposed therebetween.   The exhaust duct includes a large exhaust duct that exhausts the entire cooling medium existing on one side of the work, and a local exhaust duct that discharges the cooling medium from a local surface with an opening adjacent to the local surface of the work. The heat treatment apparatus for an aluminum alloy material according to claim 4 or 5, wherein   The heat treatment apparatus for an aluminum alloy material according to claim 4, wherein the outlets of the plurality of spray nozzles and the openings of the exhaust duct face the workpiece from the same direction.   The heat treatment apparatus for an aluminum alloy material according to claim 7, wherein the outlet of the spray nozzle and the opening of the exhaust duct face the workpiece surface in an arrangement adjacent to each other.   The aluminum alloy material according to any one of claims 4 to 8, wherein suction means for discharging a cooling medium in the cooling booth to the outside of the cooling booth is disposed in the exhaust duct. Heat treatment equipment.