JPH03219030A - Manufacture of noble metal matrix composite - Google Patents

Abstract

PURPOSE:To obtain a noble metal matrix composite having a structure in which a noble metal and an oxide are dispersed and excellent in joining strength and high temp. creep strength by spraying the molten body of a noble metal alloy on the surface of a laminar noble metal under an oxidizing condition, subjecting the laminate to heat treatment and forging in the air and thereafter repeatedly executing rolling and heat treatment. CONSTITUTION:The wire rod of a Pt-Zr alloy is melted and sprayed on the laminar ingot of Pt under an oxidizing condition, e.g. in the air, and laminating is executed. This laminate is subjected to high temp. heat treatment in the air, is thereafter forged into the shape of a thin sheet, is furthermore repeatedly subjected to rolling and high temp. heat treatment for plural times and is thereafter subjected to finish forming to manufacture a Pt matrix composite of which Pt and Pt-ZrO2 are laminated, The noble metal matrix composite having stable joining strength and, furthermore, having high temp. creep strength can be manufactured.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method for manufacturing a noble metal composite material mainly used for producing glass melting crucibles, ferrite single crystal growth crucibles, analysis crucibles, evaporation dishes, etc. .

(Prior Art) Conventionally, in order to manufacture noble metal composite materials, particularly platinum-based composite materials, for the above-mentioned uses, platinum and platinum alloys are joined by hot rolling or cold rolling, or by forge welding.

(Problems to be Solved by the Invention) By the way, hot rolling bonding requires hot rolls, which makes the device large and cumbersome to handle. Furthermore, joining by cold rolling does not provide sufficient joining strength. Furthermore, with forge welding, the joint strength varies and the material strength is weak.

Therefore, crucibles made of this material tend to blister or crack during use, resulting in a short lifespan.

SUMMARY OF THE INVENTION Therefore, the present invention aims to provide a method for easily manufacturing a noble metal composite material having stable bonding strength with high efficiency and good yield.

(Means for Solving the Problems) In order to solve the above problems, the method for producing a noble metal composite material of the present invention is to melt and spray a precious metal alloy under oxidizing conditions onto a plate-shaped ingot of a precious metal. The material is then heat treated, then forged, then rolled and heat treated as appropriate, and then finished formed to produce a noble metal composite material in which a noble metal alloy and a noble metal alloy in which oxides are dispersed are bonded. be.

(Function) Since the noble metal composite material obtained by the above manufacturing method of the present invention is laminated by melting and spraying, the bonding strength between the noble metal and the noble metal alloy material in which oxides are dispersed is stable, especially during intermediate heat treatment. Since thermal diffusion occurs on the surface, the bonding strength becomes more stable. In addition, when molten spraying and laminating, oxides are dispersed, which hinders crystal growth.
As a result, the crystal grains of the precious metal in the precious metal alloy material become fine, and the crystal grains do not become coarse at high temperatures (in addition, they do not deform even at high temperatures and have high breaking strength.Furthermore, the manufacturing method of the present invention Precious metal composite materials can be made into composites by laminating from the beginning without processing individual materials separately as in the past, so they can be manufactured easily and efficiently with good yield.

(Example) An example of the method for manufacturing a noble metal composite material of the present invention will be described. 7m 100mm, width 100mm, thickness 30+r+
m plate-shaped pt ingot, P t −Z r
Wire rods containing O, 1wt% were laminated to a thickness of 30n+rn under oxidizing conditions by a spraying method, then heat treated at 1100°C for 11 hours in the atmosphere (or oxygen may be used), and then forged to a total thickness of 40mm. Rolling, heat treatment (1100℃, 1
time, in the atmosphere) four times, and then finished molding to form 0.3 mm thick Pt and 0.3 mm thick Pt ZrO.
P [composite material obtained by lamination polymerization of 2] was obtained.

On the other hand, as a conventional example, the length is 200 mm, the width is 100 mm, and the thickness is 2 m.
m Pt plate with the same size P t-Z r O,1
wt% plates were forge-welded by hammering, and then the same process as in the example was carried out to form PT with a thickness of 0.3++un and PT with a thickness of 0.3++un.
A pt composite material with 3 mm of Pt-ZrO2 bonded was obtained.

P of the example and conventional example obtained in this way [total length 70 mm from composite material, length of test part 30 mu +, width of test part 5
Take a mm test piece, temperature 1400℃, load 1kg/-
When a creep test was conducted, the test piece of the conventional example broke in 53 hours, while the test piece of the example broke in 180 hours, indicating high creep strength at high temperatures.

In addition, the Pt composite materials of the example and the conventional example were cut into 10 pieces vertically.
Take 100 test pieces of 0 mm and 10 mm width, and
When we conducted a peel test of T and Pt ZrO2 to measure the bonding strength, the average bonding strength of the conventional test piece was 31 kg.
/mm2, and the variation was 4.2kg/mm', whereas the average bonding strength of the test pieces of the example was 37kg/mm'.
It can be seen that the bonding strength is extremely high and stable, with a variation of 1.3 kg/mm2.

Note that the above example is an example of manufacturing a P composite material, but Au
It can also be applied to the production of composite materials and Ag composite materials, and similar results can be obtained.

(Effects of the Invention) As can be seen from the above explanation, according to the method for producing a noble metal composite material of the present invention, the noble metal composite material has a stable bonding strength between a noble metal and a noble metal alloy in which oxides are dispersed, and has high high temperature creep strength. It has the excellent effect of being easy to manufacture with high efficiency (and high yield).

Further, the method for producing a noble metal composite material of the present invention has the advantage that it can be applied not only to the production of a two-layer composite material but also to the production of a multi-layer composite material.

Claims (1)

[Claims] 1) A precious metal alloy is melted and sprayed under oxidizing conditions on top of a precious metal plate ingot, then heat treated and forged, then rolled and heat treated as appropriate, and then finished formed. A method for producing a noble metal composite material, which is characterized by producing a noble metal composite material in which a noble metal alloy in which a noble metal and an oxide are dispersed are bonded together.