JPS6187838A - Copper alloy having superior hot workability - Google Patents

Abstract

PURPOSE:To improve the inferior hot workability of a Cu-Co-Si alloy by making the S content as low as possible and adding a specified amount of Mg. CONSTITUTION:This Cu alloy consists of, by weight, 0.4-4.0% Co, 0.1-1.0% Si, 0.05-1.0% Zn, 0.001-0.01% Mg, <0.003% S, 0.001-0.01% in total of one or more among 0.001-0.01% each of Cr, Ti and Zr, and the balance Cu. A Cu-Co-Si alloy has inferior hot workability because of the presence of a little S and causes heat crack and hot working crack. The inferior hot workability of the alloy can be improved by adding Mg so as to fix S in the alloy as a stable Mg-S compound, so the alloy can be hot worked into a thin plate, a bar, a pipe, a rod or a wire.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a copper alloy with excellent hot workability, and more specifically, to a copper alloy having excellent hot workability.
This invention relates to a copper alloy that has improved hot workability over Si-based alloys, so-called Corson alloys.

[Prior Art 1 Generally, Cu-Co-Si alloys have long been known as m-alloys that have relatively good electrical conductivity, high strength, and heat resistance. However, its poor hot workability made it difficult to put it into practical use, and the commercialization of thin sheets in particular was severely delayed.

[Problem to be Solved by the Invention 1] The present invention was made in view of the fact that the CuCo-Si alloy described above is difficult to hot work and its practical application has been delayed. As a result of intensive research by researchers, we have found that by processing this type of Cu-Co-8i alloy through processes such as hot working, quenching, cold working, and aging treatment, it is possible to form strips,
He realized that if it could be easily mass-produced into any shape such as plates, tubes, rods, wires, etc., many uses would open up, and he developed a tin alloy with excellent hot workability.

[Means to resolve the problem 1] 1 of the copper alloy with excellent hot workability according to the present invention. ! The characteristics are: Co 0.4-4.0w1%, SiO, 1-1.0m
L%, ZnO, 05-1, Owt%, Mg0.001
-0,01w1%, S 0.003u+1% or less, and CrO,001-0,01wt%, TiO,001
-0,01u+L%, Zr 00001-0.01u+
Select h6 types or 2 or more types from L% total 0.001
~0.01u+L%, with the remainder consisting of Cu and unavoidable impurities.

1F with excellent hot workability according to the present invention! Regarding alloys,
This will be explained in detail below.

First, the components and component ratios of the copper alloy with excellent hot workability according to the present invention will be explained.

Co content is 0.4u+L% unT:(i, Si is 0
．． Even if it is contained in the range of 1 to 1.0+j%, no improvement in strength can be expected, and 4. If the content exceeds Owj%, workability deteriorates, and no improvement in strength can be expected, although the forming price increases. Therefore, C
o content is 0.4 to 4. (Let it be lut%.

Si content is less than 0.1 wt%) 1 Co is 0.4
Even if it is contained in the range of ~4.0u+t%, no improvement in strength can be expected, and conductivity cannot be achieved.1. If the content exceeds Owt%, processability will be reduced, as well as conductivity and soldering properties will be reduced. Therefore, the Si content is set to 0.1 to 1.0w1%.

Zn is an essential element for suppressing peeling of tin plating or solder when tin plating or soldering of electronic component materials is used. If the content is less than 0.05 wt%, tin and solder The peeling suppressing effect is poor, and 1. O+
If the content exceeds ut%, the soldering performance itself becomes poor. Therefore, the Zn content is 0.05-1.0
Let it be wt%.

M is an essential element that fixes S mixed in from raw materials, furnace materials, and sulfur or sulfur compounds in the atmosphere into the alloy in the form of a stable compound with Mg, improving hot workability. If the content is less than 0,001 wt%, S will exist as a simple substance, and it will dissolve during heating or during hot working and move through the grain boundaries, causing intergranular cracking. Also, if the content exceeds 0, Olu+L%, a eutectic of Cu+MgCu□ with a melting point of 722'C will be produced, and heating to the optimum hot working temperature of 'a l> (,) ~ 900'C will result. becomes impossible.

Therefore, the Mg content is set to 0.001 to 0.01 wt%.

In addition, instead of this h season, Ca should be added at 0.001-0. O1u
A similar effect can be obtained even if +L% is included.

S is mixed in from raw materials, refractory materials such as furnace gutters, fuel, the atmosphere, etc.
It exists as a compound with metal or as a metal, and is the main cause of heat cracking or hot working cracking, and if the content exceeds 0.03 t%, Mg
Even if it contains ML%, it is difficult to form a compound with Mg.
The elemental S remains, and even by heating alone, intergranular cracking of the 5JJ lump tends to occur. Therefore, it is necessary to control raw materials, control the furnace value of refractories, and control the molten Ir atmosphere. Therefore, the S content must be 0,003 u+t% or less.

The content of Cr, Ti and Zr is 0.001 to 0.
:01 wt%, and the total of one or more of these is 0.001 to O, O1u+t%, and even if the above essential components are contained in a specific proportion, they will not be used during hot processing. C cracking cannot be completely prevented, but it can be prevented by including these elements.
If the r, Ti, and Zr contents are less than 0.001 wt%, there is no effect of suppressing cracking during hot working, and 0.01 wt%
If the content exceeds the above range, hot working cracks will not occur, but the molten metal will oxidize, making it impossible to obtain a lump with a healthy cast surface. Therefore, the Cr content is 0.001-0. Oht%, T
The i content is 0.001 to 0.01 ult%, and the Zr content is o,oot to 0.0LlIL%.Even if two or more of these are contained, the total is 0. 001-0.0but%.

In addition, in the first alloy with excellent hot workability according to the present invention, even if one or more of Mn%Fe5Ni or Sn is contained up to a total of 0.2wt%, the hot workability and product requirements will be improved. The properties, ie, electrical conductivity, strength, heat resistance, solder resistance of 1.1, heat peeling resistance of solder, etc. can be maintained at 4[i] without any practical problems.

[Example 1] Next, an example of a copper alloy having excellent hot workability according to the present invention will be described.

Example A copper alloy having the components and proportions shown in Table 1 was melted under a charcoal coating in the atmosphere in a Kryptor furnace to form a charcoal coating with a thickness of 0.
A Si3 lump of 0+nm x width 61) mm x length 180 mm was prepared.

Next, each ingot was cut into A with a thickness of 3 G 111111.
High temperature tensile test piece of STM E8, 1!7 length 5 mm
Xl1'i+120 +n+oX A test piece with a length of 180 mm for evaluating deoxidization characteristics at medium temperature and a test piece with a thickness of 40 mm x width of 50 m x length of 180 mm for evaluating hot rollability were prepared.

The temperature of the high temperature tensile test was 880°C1 tensile speed 20mm/
It was set to min.

The evaluation test for embrittlement characteristics was conducted using a three-point bending method at 20 to 8 f/mm.
A stress of 2 was applied, the temperature was maintained at 600° C. for 1 hour in a vacuum furnace, and the sample was bent at 90° with an inner bending radius of 30 mm at room temperature, and the presence or absence of cracking was investigated.

In the hot rolling test, the starting temperature was 880°C, the reduction rate for each pass was approximately 20%, and the thickness was ¥15n+m in 4 passes.
The condition of crack occurrence was investigated.

However, the rolling end temperature was 650"C1di,-L.

As a result, the copper alloy with excellent hot workability according to the present invention has
At a temperature of 600°C, which is the region most likely to become brittle during heating of an ingot, no cracks will occur even if the ingot is held at room temperature for 1 hour with a stress of 20 kgf/mm2 applied. Recognize.

It is also clear that no abnormal fractures or cracks occur even when a high temperature tensile test and a hot rolling test are conducted at a temperature of 880"C.

Regarding the copper alloy with excellent hot workability according to the present invention,
In all of the comparative alloys, intergranular cracking occurred in the high-temperature tensile test at 880° C., and it is clear that edge cracking also occurred in the hot rolling test.

[Effect of the invention 1 As explained above, the copper alloy with excellent hot workability according to the present invention has the above-mentioned (, 5 components,
It shows excellent hot workability at high temperatures and can be used to form plates, strips,
It is now possible to process into tubes, rods, and wires, including semiconductor lead frames, resistor leads, capacitor leads, terminals, connectors, switch parts such as control devices, switch parts, electronic parts such as motor rotors, and steel electromagnetic parts. It has the effect of being applicable to a wide range of applications such as stirrer casting molds and foundry casting molds.

Claims (1)

[Claims] Co0.4-4.0wt%, Si0.1-1.0wt%
, Zn0.05-1.0wt%, Mg0.001-0.
01wt%, S0.003wt%, and Cr0.001~0.01wt%, Ti0.001~0
．． 0.01wt%, one or more selected from Zr0.001~0.01wt% for a total of 0.001wt%
A copper alloy with excellent hot workability, characterized in that it contains Cu and unavoidable impurities.