JPH0270316A - Manufacture of pt/mo clad wire - Google Patents

Abstract

PURPOSE:To enlarge elongation, to prevent the generation of break at winding and to obtain the wire having uniform thickness by inserting it into a Pt pipe after plating Ni on a Mo bar, to perform hot wire drawing, then heat treating at a specified temp. after wire drawing into a required diameter. CONSTITUTION:After plating Ni on the Mo bar, inserting it into the Pt pipe, wire drawing is performed successively in a prescribed hot state after wire drawing worked into the required diameter, heat treating is operated in the temp. range of 1,050 - 1,200 deg.C, the Pt/Mo clad wire is obtained. Since the Mo bar is played with Ni, then inserted into the Pt pipe and wire drawing worked in the hot state, it is possible to join with suppressing the oxidation on the Mo surface. Further, since the heat treating is performed in the temp. range of 1,050 - 1,200 deg.C after wire drawing into the required diameter, the Pt/Mo clad wire having the sufficient elongation and tensile strength is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a method for manufacturing Pt/Mo clad wires used for vapor deposition heaters, resistance heating elements, various electrodes, and the like.

(Prior Art) Conventional Pt/Mo clad wires were made by simply inserting a Mo rod into a Pt pipe and hot wire drawing to a required diameter.

(Problem to be Solved by the Invention) By the way, the Pt/Mo clad wire made as described above may break during processing into winding wires, etc., because the mechanical properties (elongation, etc.) of Pt and Mo are different. Ta. This means that it does not have sufficient mechanical properties as a clad wire.

Furthermore, the bonding strength between Pt and Mo was insufficient because the surface of Mo was oxidized and a diffusion layer with an appropriate thickness was not formed. In order to prevent the oxidation of Mo, the bonded surface is sealed on one side and drawn in a hot state while being evacuated, but this takes time and effort. Also, the tip may be chipped and the vacuum may be broken, making it impossible to obtain craft wire of stable quality.

Therefore, the present invention aims to provide a manufacturing method that can produce a Pt/Mo clad wire that has sufficient elongation and tensile strength, and also has sufficient bonding strength between Pt and Mo.

(Means for solving problems) Pt/M of the present invention for solving the above problems.

The method for manufacturing clad wire is to apply N1 plating to a Mo rod, then insert the Mo rod into a Pt pipe and draw it hot, and after drawing it to the required diameter, heat treat it at 1050 to 1200 ° C. This method is characterized in that a Pt/Mo clad wire is obtained.

In the method for manufacturing Pt/Mo clad wire of the present invention, the reason for applying Ni plating before inserting the Mo rod into the Pt pipe is to prevent oxidation of the surface of the Mo rod during hot wire drawing. It is for this purpose. Also, after wire drawing to the required diameter, 1050~
The reason for heat treatment at 1200℃ is that if it is less than 1050t', processing strain will not be removed and mechanical properties (especially elongation) will not be improved, and if it exceeds 1200℃, crystal grains will coarsen.
This is because the diffusion layer becomes thicker and embrittlement occurs.

(Function) In the above method for producing a Pt/Mo clad wire of the present invention, a Mo rod is plated with Ni and then inserted into a Pt pipe and hot wire drawn.

Can be bonded with completely suppressed surface oxidation. Furthermore, since the wire is drawn to the required diameter and then heat treated at 1050 to 1200°C, a Pt/Mo clad wire with sufficient elongation and tensile strength can be obtained.

(Example) To explain one example of the method for manufacturing the Pt/Mo crab wire of the present invention, the outer fJE is 3.78 mm and the length is 800 mm.
After applying Ni plating to 5 μm on a Mo rod with an outer diameter of 4.
Insert it into a Pt pipe with a diameter of 45 mm, an inner diameter of 3.85 mm, and a length of 800 marks, and draw it sequentially at a temperature of 800°C.Finally, draw it in a cold state to obtain an outer diameter of 0.254++m% Pt thickness. A 0.015 mm Pt/Mo clad wire was obtained.

This Pt/Mo crab wire was heated to 900℃ (comparative example)
, 1100°C (Example 1), 1150°C (Example 2)
), heat treated at 1200°C (Example 3).

On the other hand, as a conventional example, M has the same dimensions as the example.

Without Ni plating, the rod was inserted into a PT vibrator with the same dimensions as in the example, and then hot wire-drawn at 800°C, and finally cold wire-drawn to form a wire with the same dimensions as in the example. A Pt/Mo clad wire was obtained without heat treatment.

The mechanical properties of each of the Pt/Mo clad wires of the example, comparative example, and conventional example thus obtained were investigated, and the occurrence of folding during winding was investigated, and the results shown in the table below were obtained.

As is clear from the table above, Pt/Mo of the conventional example and comparative example
It can be seen that the clad wire has a small elongation and sometimes bends when wound, whereas the Pt/Mo clad wires of Examples 1 to 3 have a large elongation and sometimes does not break when wound.

Furthermore, when we inspected the cross sections of each of the above examples, comparative examples, and conventional Tararad wires, we found that in the conventional Pt/Mo clad wire, the thickness of Pt was uneven in the circumferential direction.
The Pt/Mo clad wires of Examples and Comparative Examples are pt
The thickness was uniform in the circumferential direction. This is N during wire drawing.
This is because the first plating acts as a barrier.

(Effects of the invention) As can be seen from the above explanation, according to the method of manufacturing Pt/Mo clad wire of the present invention, although the breaking load does not change much, the elongation is large and sometimes the winding is completely broken. Pt/Mo with a uniform outer Pt thickness in the circumferential direction.
This has the effect of providing crab wire.

Applicant: Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] 1. After Ni plating is applied to the Mo rod, the Mo rod is inserted into a Pt pipe and hot wire drawn. After wire drawing to the required diameter, heat treatment is performed at 1050 to 1200°C to form a Pt/Mo cladding. A method for producing a Pt/Mo clad wire, the method comprising obtaining a wire.