JPS6411097B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Field This invention is an Fe used for lead frames etc.
-Related to Ni-Co based sealing alloys, and Fe-Ni-Co based sealing alloys with excellent punchability and cutting workability. Background technology Generally, 25-35wt%Ni-13-20wt%Co-Fe
Since alloys have thermal expansion properties similar to those of glass and ceramics, they are processed into thin plates or thin wires, then punched or etched into the desired shape to make lead frames for ICs, display elements, etc.
It is widely used for the leads of ICs, transistors, reed switches, etc., and is produced continuously in large quantities during manufacturing. The lead frames and leads mentioned above have very fine patterns and require extremely high dimensional accuracy, so conventional Fe-Ni-Co sealing alloys have poor punching workability when punched using a high-speed press. Bad,
There was a problem in that the molding molds were severely worn, the press molds had to be repaired and polished frequently, and the production efficiency was lowered, leading to a rise in product costs. Purpose of the Invention The object of the present invention is to provide a Fe--Ni--Co sealing alloy that has improved press punchability and cutting workability. Structure and Effects of the Invention The present invention has been made by studying various alloy compositions for the purpose of improving punchability and cutting workability of Fe-Ni-Co sealing alloys. Mn, Si and Al, Zr, Ca, uniformly dispersed within
By specifying the size of nonmetallic inclusions such as Mg, R and E nitrides, carbides, oxides, and sulfides, the punchability and cutting workability of Fe-Ni-Co sealing alloys has been significantly improved. This is what we found to improve the results. That is, this invention includes Ni 25-35wt%, Co 13-20wt%, Si 0.03-0.50wt%, C 0.05wt% or less, Mn 0.05-1.00wt%, S 0.003-0.025wt%, provided that Mn/S ≧10, contains O 100ppm or less, N 50ppm or less,
Alternatively, it further contains 0.0005 to 0.10 wt% of at least one of Al, Zr, Ca, Mg, and R/E, with the remainder consisting of Fe and inevitable impurities, including Si, Mn, and Al, Zr, Ca, Mg Fe-Ni-Co with good punchability, characterized by fine nonmetallic inclusions of 3 μm or less such as oxides, nitrides, carbides, and sulfides of R and E being uniformly dispersed within the structure. It is a series sealing alloy. Generally, when a Fe-Ni-Co sealing alloy is punched and cut using a die 7 and a punch 8 as shown in Fig. 3, the cut surface state is as shown in Fig. 1, which is the plane of the material to be punched. A sagging surface 2, a sheared surface 3, which is continuous from the part 1,
It consists of a fractured surface 4 and a burred surface 5,
In this case, it is known that the relationship between the punch stroke l, which is the travel distance of the punch, and the shear resistance R, which is the force required for cutting, is a curve as shown in FIG. In Figure 2, the smaller the maximum shear resistance and the smaller the punch stroke until breakage, the smaller the energy required for cutting, the less the load on the mold, and the longer the mold life. , is determined by mechanical strengths such as tensile strength and hardness of the material to be punched, and the punch stroke until cutting and (sheared surface thickness/plate thickness) are almost directly proportional. In addition, it is believed that (sheared surface thickness/plate thickness) is greatly influenced not only by the mechanical strength of the material but also by the internal properties of the material, such as the amount of trace elements, precipitates, and inclusions. By limiting the composition and specifying the size of non-metallic inclusions, (sheared surface thickness/plate thickness) can be reduced, the punch stroke until cutting can be reduced, and the life of the mold can be extended. Reason for composition limitation Ni is a basic component of this alloy that requires strong adhesive bonding with hard glass, alumina ceramics, etc., and is selected appropriately taking into account the Co content, but it must be less than 25wt%. Then, the coefficient of thermal expansion becomes too small, and if it exceeds 35wt%, the coefficient of thermal expansion becomes too large, and the deviation from the coefficient of thermal expansion of glass and ceramics increases, so it is not preferable, so it is limited to 25wt% to 35wt%. . Co is a basic component of this alloy that requires strong adhesive bonding with hard glass, alumina ceramics, etc., and is selected appropriately taking into account the Ni content. If the coefficient becomes too small and exceeds 20 wt%, the coefficient of thermal expansion becomes too large, and the deviation from the coefficient of thermal expansion of glass or ceramics becomes large, which is not preferable, so it is limited to 13 wt% to 20 wt%. Si is a deoxidizing element that prevents the generation of bubbles in the ingot, and also has the effect of improving the adhesion of the surface oxide film, which is important when sealing glass, but if it is less than 0.03 wt%, it has no effect. If the content exceeds 0.50wt%, the material hardens and cold workability deteriorates, which is not preferable, and the content is limited to 0.03wt% to 0.50wt%. C is limited to 0.05 wt % or less because it is generated as a gas from the surface during the heating process during close contact with glass or ceramics and is included in the sealing interface, reducing the sealing strength. Mn has the effect of improving hot workability, but
If it is less than 0.05wt%, it has no effect, and if it exceeds 1.00wt%, the coefficient of thermal expansion becomes too large, which impairs the sealing properties with glass and ceramics, so 0.05wt%
Limited to ~1.00wt%. S combines with Mn in the alloy to produce fine sulfides, which are uniformly dispersed within the structure and improve press workability, but if it is less than 0.003wt%, the improvement effect is small; If it exceeds the limit, it becomes easy to generate huge Mn sulfides, and defects such as surface peeling and cracking are likely to occur when processing into thin plates, etc.
Limited to 0.003wt% to 0.025wt%. The content ratio of Mn and S, Mn/S, is limited to prevent Mn and uncontained S from remaining in the structure, reducing hot workability and making defects such as cracks more likely to occur. It is necessary to satisfy Mn/S≧10. However, the upper limit is preferably 300,
A preferable Mn/S range is 35 to 200. O, N are Si, Mn, from the viewpoint of press punchability.
As oxides and nitrides of Al, Zr, Ca, Mg, and R/E (rare earth elements), it is desirable that minute inclusions are uniformly distributed within the structure, and the hot workability and cold workability are improved. From the viewpoint of improving workability, O is
It is necessary to keep it below 100ppm, and N needs to be below 50ppm. Al, Zr, Ca, Mg, R・E (rare earth elements) are
Since it has a stronger affinity with S, O, C, and N than Ni and Fe, it produces oxides, carbides, nitrides, and sulfides, and has the effect of improving press workability, so at least one of the above elements Add seeds,
If it is less than 0.0005 wt%, the above effects will not be obtained, and if it exceeds 0.10 wt%, hot workability and cold workability will be deteriorated, which is not preferable, so the content should be from 0.0005 wt% to 0.10 wt%. Further, the above-mentioned R/E (rare earth element) may be at least one kind of rare earth element, and La, Ce, and Mitsushi metal are preferable from the viewpoint of cost. Fe constitutes the basic composition of the present alloy, and is the residual range containing the various elements mentioned above. Oxides of Si, Mn, Al, Zr, Ca, Mg, R・E,
The reason for limiting the size of nonmetallic inclusions such as carbides, nitrides, and sulfides in the structure is that if the size of nonmetallic inclusions exceeds 3 μm, there will be a lot of burrs during punching and cutting. This is because they become the starting point for cracks and fractures during bending and drawing of thin plates, so it is important that the size of the nonmetallic inclusions is 3 μm or less and that they are uniformly dispersed and contained within the structure. It is. In addition, in this invention, in order to reduce the size of nonmetallic inclusions in the alloy composition to 3 μm or less and to uniformly disperse and distribute them, melting conditions, agglomeration conditions, and the timing and amount of addition of the deoxidizing agent are appropriately adjusted. It is necessary to select. Further, the preferred composition range of this invention alloy is:
Ni25-35wt%, Co13-20wt%, Si 0.01-0.30wt%, C 0.03wt% or less, Mn 0.35-0.85wt%, S 0.003-0.015wt%, however, Mn/S = 35-200, O 100ppm or less , N 500ppm or less, or further contains 0.0005 to 0.05wt% of at least one of Al, Zr, Ca, Mg, and R/E, with the remainder consisting of Fe and unavoidable impurities,
It is preferable that fine nonmetallic inclusions of 3 μm or less are uniformly dispersed at 60 ppm or more. Examples Fe--Ni--Co based sealing alloys having various composition ranges within the scope of the present invention and outside the scope of the present invention as shown in Table 1 were manufactured under the same conditions and finished into thin plates with a thickness of 0.25 mm. A sample with a width of 8 mm x length of 50 mm was taken from this thin plate, and as shown in Fig. 3, using a compression tester, the sample 6 placed on the die 7 was tested with a width of 7 mm x length of 10 mm.
Press punching was performed using a punch 8 of mm size, the punch stroke l was measured by the moving distance of the movable arm of the testing machine, and the shear resistance R was measured by a load cell. From this, a relationship diagram between shear resistance R and punch stroke l similar to that shown in FIG. 2 was obtained, and the punch stroke up to cutting was actually measured. In addition, the cut cross section of the sample after punching was observed with an optical microscope, the sheared surface thickness and plate thickness were measured, and (sheared surface thickness/plate thickness) was calculated. The amount of inclusions in various alloys can be determined by dissolving only the metal using a constant potential electrolysis method, and removing non-metallic inclusion residues such as oxides, carbides, nitrides, and sulfides from the solution using a microfilter with a size of 3.0 μm or less. The particles were separated and measured into those larger than 3.0 μm and those larger than 3.0 μm. The above measurement results are shown in Table 1 along with the mechanical strength and thermal expansion properties of the samples. As is clear from Table 1, according to this invention
The Fe-Ni-Co sealing alloy has much smaller punch stroke and (shear surface thickness/plate thickness) until cutting than the conventional alloy in the comparative example, which may impair the required thermal expansion characteristics and mechanical strength. It is clear that the punching and cutting workability has been improved, and it can be seen that this has a great effect on extending the life of the mold.

【table】

【table】 [Brief explanation of drawings]

Figure 1 is a perspective view showing a cut section of Fe-Ni-Co sealing alloy, and Figure 2 is a punch stroke l.
It is a graph which shows the relationship between and shear resistance R. Third
The figure is an explanatory diagram of a compression test apparatus in an example. DESCRIPTION OF SYMBOLS 1... Flat part, 2... Sagging surface, 3... Sheared surface, 4... Fractured surface, 5... Burr surface, 6... Sample, 7... Die, 8...
Punch.

Claims (1)

[Claims] 1 Ni 25-35wt%, Co 13-20wt%, Si 0.03
~0.50wt%, C 0.05wt% or less, Mn 0.05~
1.00wt%, S 0.003~0.025wt%, however, Mn/
Contains S≧10, O 100ppm or less, N 50ppm or less,
The remainder consists of Fe and unavoidable impurities, and fine non-metallic inclusions of 3 μm or less are uniformly dispersed within the structure, resulting in good punchability.
Fe-Ni-Co sealing alloy. 2 Ni 25-35wt%, Co 13-20wt%, Si 0.03
~0.50wt%, C 0.05wt% or less, Mn 0.05~
1.00wt%, S 0.003~0.025wt%, however, Mn/
S≧10, at least one of Al, Zr, Ca, Mg, R・E
Contains 0.0005 to 0.10 wt% of seeds, 100 ppm or less of O, 50 ppm or less of N,
The remainder consists of Fe and unavoidable impurities, and fine non-metallic inclusions of 3 μm or less are uniformly dispersed within the structure, resulting in good punchability.
Fe-Ni-Co sealing alloy.