JP2000015426A - Repair/improvement method for defect/defect in structure inside metal member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To repair/eliminate a casting defect and a defect in structure, which are likely generated inside a metal member, without deteriorating a shape and dimensional precision of a metal member. SOLUTION: When repairing/eliminating a casting defect and a defect in structure inside a metal member 2, friction heat is generated inside the metal member 2 by a small diameter rod part 1d of a rotating rod 1 so as to form a plastic fluidized layer 2H, and an inside of the metal member 2 is agitated by the plastic fluidized layer 2H, so that a casting defect and a defect in structure inside the metal member 2 are repaired and eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing / improving a defect / defect in a metal member which is suitable for repairing a defect present inside a metal member or improving a defect in a structure. is there.

[0002]

2. Description of the Related Art In a metal member, casting defects called cavities or pores may occur, or a structural defect may occur due to a difference in cooling speed or cooling time.

[0003] When such defects / structural defects inside the metal member are remarkable, they may be discarded. In some cases, however, such processing is performed by applying plastic working or performing heat treatment. Repair and improvement of various defects and organizational defects.

[0004]

However, if the metal member has a complicated shape or has a hollow portion, it is necessary to repair defects / defects in the metal member by plastic working. It is often difficult to improve, and it is often difficult to repair casting defects by heat treatment.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is intended to improve the shape accuracy and dimensional accuracy of a metal member having a complicated shape or a hollow product. It is an object of the present invention to provide a method for repairing / improving a defect / structure defect inside a metal member, which is suitable for repairing a casting defect or improving a metal structure, particularly at a necessary portion of the metal member, without lowering the metal structure. .

[0006]

According to the present invention, there is provided a method for repairing / improving a defect / texture defect inside a metal member according to the present invention. In doing so, frictional heat is generated inside the metal member by the rotating rod to form a plastic fluidized layer, and the inside of the metal member is stirred by the plastic fluidized layer to repair and improve defects / defects in the metal member. It is characterized by doing so.

In the embodiment of the method for repairing / improving a defect / texture defect inside a metal member according to the present invention, the rod generates frictional heat inside the metal member. The plastic fluidized bed may be provided with a small-diameter rod portion for stirring the inside of the metal member with the plastic fluidized bed and a large-diameter rod portion continuous with the small-diameter rod portion.

[0008] Similarly, in an embodiment of the method for repairing / improving a defect / texture defect inside a metal member according to the present invention, the rod has a softening temperature higher than the softening temperature of the metal member. It is more desirable to use a material having

In another embodiment of the present invention, the metal member is made of an aluminum alloy, and the rod is made of stainless steel. Can be comprised.

Similarly, in an embodiment of the method for repairing / improving a defect / texture defect inside a metal member according to the present invention, frictional heat is generated inside the metal member by the rotating rod. Then, the plastic fluidized bed is formed, and the rod is moved in the surface direction of the metal member while the inside of the metal member is stirred by the plastic fluidized bed.

[0011]

1 to 3 show one embodiment of a method for repairing / improving a defect / texture defect inside a metal member according to the present invention. In the present invention, a rod illustrated in FIG. 1 is used. Use 1.

The rod 1 has a small-diameter rod portion 1d having a function to be described later and a large-diameter rod portion 1D connected to the small-diameter rod portion 1d, and is connected to a rotation driving device (not shown). It can rotate at high speed (for example, at a rotation speed of 1000 to 2000 rpm) in the direction of arrow A of FIG.

When repairing / improving defects / texture defects inside the metal member using such a rod 1, the rod 1 shown in FIG. 1 is rotated at a high speed while the rod 1 shown in FIG. Contact

When the tip of the small-diameter rod portion 1d of the rod 1 is pressed against the surface of the metal member 2, frictional heat is generated at that portion, and the heat generation temperature gradually rises and softens on the surface of the metal member 2 to cause plastic flow. becomes possible, as a result, the plastic flow layer or heat-affected zone 2H _1, 2H _2, 2H ₃ is also formed with a small diameter rod portion 1d is lowered further into the interior of the metal member 2 by plastic flow layer 2H is formed .

Therefore, since the plastic fluidized bed 2H is agitated inside the metal member 2, casting defects that may have been present in this portion are repaired and the structure defect is improved to a leveled one. Is done.

Further, in some cases, while continuing stirring in the plastic fluidized bed 2H by the small diameter rod portion 1d as shown in FIG. 2, the rod 1 is moved in the plane direction of the metal member 2 as shown in FIG. (In the direction of arrow B shown in FIG. 3), the plastic flow layer always enters behind the rod 1 under the pressure of plastic flow, so that casting defects are repaired in a desired trajectory and the metallographic structure is formed. Will be leveled and the organization will be improved.

In this case, it is desirable to use a material having a softening temperature higher than the softening temperature of the metal member 2 as a material of the rod 1, and as shown in FIG. It is desirable if necessary to use the one formed with

[0018]

In this embodiment, the metal member 2 is applied to a cylinder head of an engine made of an aluminum alloy for casting (AC8A).

Since such an aluminum alloy cylinder head has an intake port and an exhaust port and has a cooling water passage, it is manufactured by casting using a core.

Therefore, a casting defect or a structural defect may be generated inside the cylinder head which is a casting product.

When a liner or the like is provided in the intake port or the exhaust port, a casting defect or a structural defect may not be a serious problem in some cases. However, when a liner is not provided in the port, a cooling water passage or a valve seat is not provided. In some cases, it is necessary to prevent casting defects or structural defects from occurring in the portion or the seal portion with the cylinder block as the mating material.

Therefore, in such a case, a small-diameter rod portion 1d having a diameter of 5 mm and a protruding length of 7 mm and a diameter of 20 mm are attached to the metal member 2 made of an aluminum alloy cylinder head.
using a rod 1 having a large-diameter rod part 1D
The rod 1 is pressed against the surface of the metal member 2 while being rotated at a high speed of about 1200 rpm in the direction of the arrow A in the drawing, and firstly, a frictional heat is generated and softened at this portion to form a plastic fluidized layer 2H with a depth of about 8 mm. And a plastic fluidized bed or heat-affected zones 2H ₁ , 2H ₂ , 2H ₃ are formed therearound, and furthermore, as shown in FIG. In the embodiment, the sealing surface between the mating cylinder block and the mating material cylinder block is moved in a direction to make one round.

As a result, casting defects are not present over the entire circumference of the sealing surface between the aluminum alloy cylinder head and the mating cylinder block, and the metal structure is evenly leveled. I was

The metal member (cylinder head) 2 is
Since the temperature rise is suppressed to such an extent that plastic flow is possible, and the molten state is not reached, the dimensional and shape accuracy did not decrease.

[0025]

According to the method for repairing / improving a defect / texture defect inside a metal member according to the present invention, when repairing / improving a defect / texture defect inside a metal member as described in claim 1, The rotating rod generates frictional heat inside the metal member to form a plastic fluidized bed, and the plastic fluidized bed stirs the inside of the metal member to repair and improve defects / structural defects inside the metal member. Even when a casting defect or a structural defect is present inside a metal member, it is possible to repair and improve the casting defect or the defective structure without impairing the shape and dimensional accuracy of the metal member. The effect is brought about.

And, as described in claim 2,
The rod has a small-diameter rod portion that generates frictional heat inside the metal member to form a plastic fluidized bed and stirs the inside of the metal member with the plastic fluidized bed, and a large-diameter rod portion connected to the small-diameter rod portion. By doing so, it is possible to satisfactorily generate frictional heat inside the metal member and to have sufficient mechanical strength of the rod, and furthermore, a step between the small-diameter rod portion and the large-diameter rod portion. This has a remarkably excellent effect that the depth of the plastic fluidized bed can be made uniform.

According to a third aspect of the present invention, the rod is made of a material having a softening temperature higher than the softening temperature of the metal member. A remarkably excellent effect is obtained that the material stirring in the inside can be made good.

Further, as described in claim 4,
The metal member is made of an aluminum alloy, and the rod is made of stainless steel, so that the rod can be used to repair and improve casting defects and structural defects in metal members such as cylinder heads for engines made of aluminum alloy for casting. A remarkably excellent effect is obtained that it can be performed without causing the aluminum alloy to adhere.

Still further, as described in claim 5, the rotating rod generates frictional heat inside the metal member to form a plastic fluidized bed, and the rod is agitated inside the metal member by the plastic fluidized bed. Is moved in the plane direction of the metal member, it is possible to repair and improve casting defects and structural defects inside the metal member with a desired trajectory shape.For example, in the case of an engine cylinder head, A remarkably excellent effect is obtained in that it is possible to repair a casting defect and to improve a structural defect on a locus along a seal surface with a cylinder block as a mating material.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a rod structure according to an embodiment of a method for repairing / improving a defect / texture defect inside a metal member according to the present invention.

FIG. 2 is an explanatory sectional view showing a positional relationship between a rod and a metal member according to an embodiment of a method for repairing / improving a defect / texture defect inside a metal member according to the present invention.

FIG. 3 is an explanatory plan view showing a moving direction of a rod on a metal member surface according to an embodiment of a method for repairing / improving a defect / texture defect inside a metal member according to the present invention.

FIG. 4 is an explanatory view showing a preferred form of a rod in a method for repairing / improving a defect / texture defect inside a metal member according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rod 1d Small diameter rod part of rod 1D Large diameter rod part of rod 2 Metal member 2H Plastic flow layer of metal member 2H ₁ , 2H ₂ , 2H ₃ Plastic flow layer of metal member or heat affected zone

Claims (5)

[Claims] (1) repairing defects / structural defects inside a metal member;
In the improvement, a rotating rod generates frictional heat inside the metal member to form a plastic fluidized bed, and the plastic fluidized bed stirs the inside of the metal member to repair / improve defects / defects in the metal member. Repair / improvement method for defects / texture defects inside a metal member. 2. The rod has a small-diameter rod portion that generates frictional heat inside the metal member to form a plastic fluidized bed and stirs the inside of the metal member with the plastic fluidized bed, and a large-diameter rod portion connected to the small-diameter rod portion. 2. The method for repairing / improving a defect / texture defect inside a metal member according to claim 1, comprising: 3. The method according to claim 1, wherein the rod is made of a material having a softening temperature higher than a softening temperature of the metal member. 4. The metal member is made of an aluminum alloy,
4. The method according to claim 1, wherein the rod is made of stainless steel. 5. The rotating rod generates frictional heat inside the metal member to form a plastic fluidized bed, and moves the rod in a plane direction of the metal member while stirring the inside of the metal member with the plastic fluidized bed. 5. The method for repairing / improving a defect / texture defect inside a metal member according to any one of the above items 4 to 4.