JPH05171315A - Joining method of oxides dispersion strengthened platinum and platinum alloy - Google Patents

Abstract

PURPOSE:To increase and stabilize the weld strength by increasing the weld width and implementing building up by welding, thereby dispersing the stresses and preventing coagulation and floating of dispersion oxides. CONSTITUTION:After flat end surfaces of oxides dispersion strengthened platinum (alloy) 1 are butted, joining by plasma welding using an electrode of the same material is implemented forming the fusion zone 2 to be a joining surface whose section is of inverted triangle where the weld width on one side is large while the weld width on the other side is small. Successively, further cladding by welding is implemented using an electrode of the same material, and a built-up part 3 which is wider than the weld width on one side and joined in a two-stepped manner is formed. The boundary between the weld zone and an un-welded zone is inclined, and the weld srength is remarkably stabilized due to effective dispersion of the stresses. This joining method also allows the plate thickness to be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of bonding strength of oxide dispersion strengthened platinum and platinum alloy such as ZrO ₂ used in glass fiber spinning equipment, glass melting equipment, high temperature equipment, etc. It concerns the improvement of the structure.

[0002]

2. Description of the Related Art Conventionally, the joining of the above-mentioned materials has been performed by melting and joining the flat end faces with each other and plasma welding or the like using a welding rod made of the same material. However, the bonding strength is weak and unstable, and improvement thereof has been strongly demanded. This is because as a result of welding, oxides that are uniformly dispersed in the material are aggregated and further rise to the surface layer and become non-uniform, so that the effect of suppressing the coarsening of crystal grains at high temperature cannot be exerted. Conceivable.

[0003]

OBJECTS OF THE INVENTION The object of the present invention is to provide a method for joining oxide dispersion strengthened platinum and platinum alloys which has a high welding strength and is stable.

[0004]

The technical means of the present invention for solving the above-mentioned problems are characterized by widening the welding width and carrying out the overlaying in the flat end face butt fusion welding of oxide dispersion strengthened platinum and platinum alloy. Is to

[0005]

According to the oxide dispersion-strengthened platinum and platinum alloy of the present invention configured as described above, by widening the welding width, it is possible to receive and disperse stress in a wide portion, and thus, especially in the case of melt bonding having an inverted triangular cross section. In the above, the boundary between the melted portion and the unmelted portion is slanted so that the stress is effectively dispersed, and the welding strength is strong and stable. Also,
Welding with a low melting temperature (immediately above the melting point) can be prevented by dividing the build-up several times, and it is possible to prevent agglomeration and embossing of dispersed oxides, and also increase the plate thickness and weld strength Is strong and stable.

[0006]

EXAMPLES Examples and conventional examples will be described below. First, as an example, material PtZrO ₂ 0.06%, plate thickness 0.8 mm, width 1
00mm oxide-dispersion-strengthened platinum 1 was flat-faced as shown in Fig. 1, and then plasma welding was performed using a welding rod of the same material. The welding width of the surfaces was narrowed and the surfaces were joined at the joining surface having an inverted triangular cross section. Then, the welded portion is further padded, the padded portion is made wider than the welded width of the one surface, and the padded portion is welded in two steps with the one-sided weld width of 3 to 4 mm as shown in FIG. Three
The creep test piece 4 having

Further, as a conventional example, oxide dispersion strengthened platinum 1 having the same size and material as those of the embodiment is abutted with flat end faces as shown in FIG. 4, and then plasma welding is performed using a welding rod of the same material as shown in FIG. As described above, a creep test piece 6 was obtained in which the fusion zone 5 was joined at the joining surface having an inverted triangular cross section with an upper fusion width of 1 to 2 mm.

However, the temperature is 1400 ° C. and the load is 0.41 kgf / mm ²
As a result of each creep test, in the conventional example, the fracture time averaged 26 hours and the variation was 10 hours, and the bonding strength was weak and unstable, whereas in the example, the fracture time averaged 42 hours, the variation 6 hours. It was strong and stable.

[0009]

As described above, according to the present invention, it is possible to effectively disperse the stress received by widening the welding width and carrying out the overlay, and to prevent the aggregation and the protrusion of the dispersed oxide and to reduce the plate thickness. It also becomes thicker and the welding strength becomes stronger and stable. Therefore, it has an excellent effect that a device having good quality and long life can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a butt state during welding according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state in the middle of welding according to an embodiment of the present invention.

FIG. 3 is a diagram showing oxide dispersion strengthened platinum of one example of the present invention.

FIG. 4 is a view showing a butt state during conventional welding.

FIG. 5 is a view showing a conventional oxide dispersion strengthened platinum.

[Explanation of symbols]

 1 Oxide dispersion strengthened platinum 2 Melt part 3 Overlay part 4 Creep test piece having overlay part

Claims (1)

[Claims] 1. A method for joining oxide-dispersion-strengthened platinum and a platinum alloy, which comprises widening a welding width and performing padding in flat end face butt fusion welding of oxide-dispersion-strengthened platinum and a platinum alloy.