JPH04355131A - Preparation of damping structure excellent in tenacity - Google Patents

Abstract

PURPOSE:To enhance tenacity, in the damping structure of a railroad or the like, by constructing a welded structure using a thick damping metal plate wherein an inorg. damping material is held between metal plates and subsequently removing the stress of said structure by annealing. CONSTITUTION:Thick damping metal plates each formed by arranging an inorg. damping material 2, for example, a pure iron type steel plate containing coarse crystal grains and reduced in the content of impurity elements or a steel plate containing flaky graphite between two thick plates 1, 1a such as steel plates are welded at welding parts 3 to construct a welded structure which is, in turn, subjected to stress removing annealing. By this method, the stress removing annealing of the welded structure using thick plates as structural members can be certainly performed and the welded structure excellent in tenacity can be stably obtained.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a vibration damping structure with excellent toughness.

0002

BACKGROUND OF THE INVENTION In recent years, the impact of noise from transportation such as automobiles, trains, and vehicles, as well as noise and vibration from factories and construction sites, on surrounding residents is increasing day by day, and has become a major social problem. As a means of solving this problem, research and development of vibration-absorbing materials in which the material itself has vibration-absorbing ability is progressing. It is used as a structural material. With the expansion of applications, there is a demand for damping materials that use thick plates in addition to the conventional damping materials that use thin plates as skin plates.

0003

However, in welded structures using thick plates, welding introduces residual stress into the structural members, which deteriorates the material quality. In order to prevent this deterioration of material quality, stress relief annealing (improvement of toughness) is essential for welded structures using thick plates. An object of the present invention is to provide a method for manufacturing a damping structure with excellent toughness using a damping material that can withstand this heat treatment.

0004

[Means for Solving the Problems] The present invention is characterized in that a welded structure is constructed using a thick damping metal plate in which an inorganic damping material is placed between two metal plates, and then A method for manufacturing a vibration-damping structure with excellent toughness, characterized by subjecting the structure to stress relief annealing. As a metal plate,
For example, a steel plate, a stainless steel plate, a nonferrous metal plate, etc. can be used, and the thickness is preferably 1.6 to 50 mm, and 1.6 m.
If it is less than 50mm, it is out of the field of thick plate, and 50mm
There is currently almost no use for super thick plates, so this range is used. An inorganic vibration damping material is used as a material to be placed between such thick plates in order to enable stress relief annealing. This inorganic damping material is pressed onto the upper and lower thick metal plates by hot rolling or the like. However, in structures that use resin sandwich-type thick metal plates made of conventional organic resin as structural members, stress relief annealing melts the resin between the metal plates and causes it to drip. It flows out and ignites,
Also, the two metal plates come apart at the same time that the edge of the plate ignites, causing a fire. However, as in the present invention, by arranging an inorganic damping material between the upper and lower thick plates,
Even if it is placed in a high temperature environment during stress relief annealing, it will not ignite and cause a fire, and the two metal plates will not separate. Examples of this inorganic damping material include pure iron steel sheets with coarse grains and few impurity elements, steel sheets containing flaky graphite,
A metal plate having fine voids inside, an Al or Cr metal plate, etc. with excellent vibration damping properties can be used. The thickness is preferably 0.1 to 7.0 mm. If the thickness is less than 0.1 mm, the damping performance will decrease, and if it exceeds 7.0 mm, the damping material will generally have worse weldability than the thick plates above and below, so the weldability will decrease due to the influence of this damping material. , this range. In a structure having a thick damping metal plate as a structural member according to the present invention as described above, stress relief annealing, which is essential for a welded structure using a thick plate, becomes possible. As such a structure, various structures such as a box type, a joint structure type, etc. can be applied.

[0005]

[Examples] Next, examples of the present invention will be described together with comparative examples. Welded structures made of thick metal plates and vibration damping materials shown in Table 1 below were subjected to stress relief annealing shown in Table 2, and results regarding vibration damping properties were obtained. In Tables 1 and 2, Examples 1 to 4 show examples of the present invention, and Examples 5 and 6 show comparative examples. Examples 1 to 4 are capable of stress relief annealing and have high toughness.
The loss coefficient, which indicates vibration damping properties, is also high. In Example 5, the layer thickness of the damping material is too thin and the loss coefficient is low. In Example 6, since an organic resin is used as the damping material, stress relief annealing is not possible, so the toughness is low.

[0006]

[Table 1]

[0007]

[Table 2] In Tables 1 and 2, Note 1: The loss coefficient is calculated based on the thick metal plates 1 and 1 as shown in Figure 1.
A cubic box of 600 mm on a side is made of A and vibration damping material 2, and all corners are joined by welding 3. Measurements were taken after stress relief annealing. However, in Example 6, stress relief annealing was not possible, so measurements were taken without stress relief annealing. Note 2: Stress relief annealing is performed by increasing the temperature to 600℃ and 200℃.
Cooling was performed at a rate of 50° C./hr. Note 3: Pure iron steel sheet has C0.005% and Mn0.08%.
, Si 0.09% Other impurities total 0.20%, balance Fe
. Note 4: Steel plates with voids have a porosity of 20% and an average void volume of 0.
．． 05cm3. Note 5: Sintered metal plate has a porosity of 30% and an average void volume of 0.0.
6cm3. Note 6: Toughness is expressed as Charpy absorbed energy at a test temperature of 0°C. In addition, for those whose plate thickness was less than 10 mm, the value was calculated per 80 mm2 and displayed.

[0008]

[Effects of the Invention] By doing this, stress relief annealing of welded structures using thick plates as structural members can be reliably achieved, and welded structures with excellent toughness etc. can be industrially stably produced. It can have a great effect.

[Brief explanation of the drawing]

FIG. 1 (A) is a perspective explanatory view of a structure used in an embodiment of the present invention, and (B) is an explanatory view in the direction of arrow A in (A).

[Explanation of symbols]

1, 1a Thick metal plate 2. Damping material 3 Welded part

Claims (2)

[Claims] Claim 1: A welded structure is constructed using thick damping metal plates with an inorganic damping material arranged between the metal plates, and the structure is then subjected to stress relief annealing, which improves toughness. A method for manufacturing a structure with excellent vibration damping properties. 2. The structural member is a thick damping metal plate in which an inorganic damping material with a thickness of 0.1 to 7.0 mm is arranged between metal plates with a thickness of 1.6 to 50 mm. A method for manufacturing a damping structure with excellent toughness.