JP6628082B2 - Method for producing Fe-Ni alloy thin plate - Google Patents

Description

  The present invention relates to a method for manufacturing an Fe—Ni-based alloy thin plate used for a lead frame, a metal mask, and the like, for example.

  An Fe—Ni-based alloy thin plate used for a lead frame, a metal mask, or the like has, for example, an application in which it is used by being bonded to a resin or the like. As a method of improving the adhesion to such a resin, for example, in Japanese Patent Application Laid-Open No. S60-11447 (Patent Document 1), a desired roughness is obtained by directly polishing a Fe—Ni alloy thin plate or pickling it. I'm trying. In Japanese Patent Application Laid-Open No. 10-270629, there is an invention in which a rolling roll is a dull roll, or a Fe—Ni-based alloy sheet after final rolling is pickled to have a desired roughness.

JP-A-60-1111447 JP-A-10-270629

Among the inventions disclosed in Patent Documents 1 and 2 described above, when pickling a Fe—Ni-based alloy thin plate after cold rolling, the balance of the stress introduced during rolling may be lost and deformation such as warpage of the material may occur. There is. Further, in the method of directly polishing, there is a possibility that abrasive grains during polishing may remain on the surface of the Fe—Ni-based alloy thin plate. Also in the method using a dull roll, a desired surface roughness may not be obtained depending on the rolling conditions.
In recent years, Fe-Ni alloy thin plates have been subjected to etching, pressing, laser processing, etc. with the application of miniaturization, thinning, and high definition. Since it is used by being joined to a member, it is desired to improve the adhesion in order to prevent oxidation and improve the joining strength.
An object of the present invention is to provide a method for producing an Fe-Ni-based alloy thin plate capable of improving the adhesion to other diversified members in a thin Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less. It is to be.

The present invention has been made in view of the above-mentioned problems.
That is, in the present invention, Ni + Co: 35.0 to 43.0% (Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, and the balance is Fe A cold rolling step of performing at least one cold rolling and continuous annealing on a cold rolling material comprising impurities and impurities, wherein the final cold finish rolling in the cold rolling step is performed using a roll roll roughness Ra. = 0.15 to 1.0 μm, rolling speed 6.5 m / s or less, rolling oil kinematic viscosity 8 mm ² / s or more, rolling oil discharge amount 35 L / s or less. This is a method for producing an Fe-Ni-based alloy thin plate for obtaining a Ni-based alloy thin plate.
Preferably, after performing the final cold finish rolling, the Fe—Ni-based alloy thin plate is washed.
More preferably, the surface roughness of the Fe—Ni-based alloy thin plate is Ra = 0.15 to 0.5 μm.

  ADVANTAGE OF THE INVENTION According to this invention, since the adhesiveness can be improved in a thin Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less, poor adhesion between the Fe-Ni-based alloy thin plate and a counterpart material that is in close contact with the thin plate. Can be prevented.

It is a figure which shows the correlation of the finish rolling roll roughness used for the last cold finish rolling, and the surface roughness of the Fe-Ni type alloy thin plate after rolling. It is a figure showing a test piece of a simple adhesion evaluation test.

Hereinafter, the present invention will be described in detail.
<Composition of Fe-Ni-based alloy>
First, the chemical composition specified in the present invention will be described. The Fe—Ni-based alloy having the composition specified in the present invention has a composition necessary to obtain a desired coefficient of thermal expansion. In addition, composition is a mass%.
[Ni + Co: 35.0 to 43.0% (however, Co is 0 to 6.0%)]
Ni and Co are elements necessary for obtaining a desired coefficient of thermal expansion. If the Ni + Co content is less than 35.0%, the austenite structure tends to be unstable, whereas if it exceeds 43.0%, the coefficient of thermal expansion increases, and the low thermal expansion characteristics are not satisfied. Therefore, the Ni + Co content is 35.0. To 43.0%. It is not always necessary to add Co, but part of Ni can be replaced by Co in a range of up to 6.0%.
[Si: 0.5% or less, Mn: 1.0% or less]
Usually, a small amount of Si and Mn is contained in a Fe—Ni-based alloy for the purpose of deoxidation, but if added excessively, segregation is likely to occur. % Or less. Although the lower limits of Si and Mn are not particularly limited, Si is added as a deoxidizing element, so that about 0.05% of Si and about 0.05% of Mn remain.
[The balance is Fe and impurities]
Other than the above elements, Fe may be substantially used, but includes impurities which are unavoidable in production. There is C as an impurity element that needs to be particularly restricted. For example, if the impurity element is used for etching, its upper limit is set to 0.05%.
To improve press punching properties, a free-cutting element such as S may be contained at 0.020% or less. An element such as B for improving hot workability may be contained at 0.0050% or less.

<Material for cold rolling>
In the present invention, a material for cold rolling is prepared through hot rolling. Since an oxidized layer is formed on the hot-rolled material, the oxidized layer is removed mechanically or chemically, for example, to obtain a material for cold rolling. Further, the edge is trimmed so that a defect such as a crack does not occur from the edge of the cold-rolled material during the cold rolling, and the material is used as a material for cold rolling. In addition, the thickness of the material for cold rolling is preferably about 2.0 to 5.0 mm.
Then, the above-mentioned cold rolling material is subjected to cold rolling and continuous annealing one or more times to obtain a desired sheet thickness, and final cold finish rolling is performed. The rolling ratio before the final cold finish rolling is set to 50 to 85%, and continuous annealing may be performed in a heating furnace at 850 to 1000 ° C for 10 to 60 seconds. Then, it is preferable that the hardness is set to 120 to 150 HV before the final cold finish rolling, and the final cold finish rolling is performed.

Next, the final cold finish rolling conditions will be described in detail.
In the present invention, the thickness of the Fe—Ni-based alloy thin plate is set to 0.25 mm or less in the final cold finish rolling. The reason why the thickness is set to 0.25 mm or less is, for example, a thickness required for use in a lead frame or a metal mask. The preferred thickness is 0.15 mm or less.
<Rolling roll roughness>
One of the important points in the present invention is that the rolling roll roughness used in the final cold finish rolling is Ra = 0.15 to 1.0 μm. In addition, the rolling roll roughness is the roughness of the surface of the roll used for rolling. The surface roughness of the Fe—Ni-based alloy thin plate manufactured by rolling is determined mainly by transferring the surface roughness of a roll used in rolling. For this reason, if the surface roughness of the rolling roll itself is low, it becomes very difficult to increase the surface roughness of the Fe—Ni-based alloy thin plate obtained by rolling. Therefore, the lower limit of the rolling roll roughness is set to Ra = 0.15 μm. The lower limit of the preferable rolling roll roughness is 0.20 μm.
Further, by making the value of the rolling roll roughness higher, the value of the surface roughness of the obtained Fe—Ni-based alloy thin plate also becomes higher. However, even if a roll having an excessively high surface roughness value is used, the roll is worn out due to a load applied to the roll surface during rolling, and it is difficult to obtain a high value of roughness. Rather, the frictional resistance increases, causing an increase in abrasion powder generated by processing, and the surface cleanliness of the Fe—Ni-based alloy thin plate deteriorates, which may be a factor that hinders adhesion. Therefore, the upper limit of the rolling roll roughness is set to 1.0 μm. The upper limit of the preferable rolling roll roughness is 0.50 μm. In addition, Ra in this specification is arithmetic mean roughness Ra defined by JIS-B-0601 (2013).

In the present invention, in addition to the above-described roughness of the rolling roll, the rolling speed, the kinematic viscosity of the rolling oil, and the discharge amount of the rolling oil are set to appropriate ranges. These three requirements are indispensable factors for adjusting the surface roughness of the Fe—Ni-based alloy thin plate. In particular, when performing the final cold finish rolling, if any of these three requirements is out of the range specified in the present invention, it becomes impossible to obtain a desired surface roughness.
<Rolling speed>
In the present invention, the rolling speed of the final cold finish rolling is set to 6.5 m / s or less. The reason for setting the rolling speed to 6.5 m / s or less is to set the surface roughness of the Fe—Ni-based alloy thin plate to Ra = 0.15 to 0.5 μm. If the rolling speed is excessively high, the amount of rolling oil bite increases, and the contact area between the roll and the Fe-Ni alloy thin plate decreases, so that the roughness of the roll becomes difficult to be transferred, and the Fe-Ni alloy The surface roughness of the thin plate is reduced. Therefore, in the present invention, the rolling speed is set to 6.5 m / s or less. A preferred upper limit of the rolling speed is 4.0 m / s. More preferably, it is 3.5 m / s. On the other hand, if the rolling speed is excessively low, the productivity is reduced and the cost is increased. Therefore, the lower limit of the rolling speed is preferably 0.5 m / s. A preferred lower limit of the rolling speed is 1.0 m / s. More preferably, it is 2.0 m / s.
<Rolling oil kinematic viscosity>
Further, the kinematic viscosity of the rolling oil used in the rolling mill used for final cold finish rolling is set to 8 mm ² / s or more. The reason for setting the kinematic viscosity of the rolling oil to 8 mm ² / s or more is to make the surface roughness of the Fe—Ni-based alloy thin plate Ra = 0.15 to 0.5 μm. If the kinematic viscosity of the rolling oil is low, the rolling oil biting amount during rolling increases, and the contact area between the roll and the Fe-Ni-based alloy thin plate decreases, so that the roll roughness becomes difficult to be transferred, and Fe- The surface roughness of the Ni-based alloy thin plate is reduced. Therefore, the kinematic viscosity of the rolling oil is set to 8 mm ² / s or more. The lower limit of the kinematic viscosity of the preferred rolling oil is 9 mm ² / s. On the other hand, if the kinematic viscosity is excessively high, the lubricating action between the Fe-Ni-based alloy thin plate and the roll during rolling is reduced, which may cause problems such as an increase in thermal crown and heat cracks. Therefore, the upper limit of the kinematic viscosity is set to 40 mm ² / s. The upper limit of the kinematic viscosity of the rolling oil is preferably 35 mm ² / s, and more preferably 20 mm ² / s.
<Rolling oil discharge amount>
Along with the above-described rolling oil kinematic viscosity, the rolling oil discharge rate also affects the roughness of the Fe—Ni-based alloy thin plate. When the rolling oil discharge amount is large, the rolling oil biting amount increases, and as the contact area decreases, it becomes difficult to transfer the roughness of the roll. Therefore, the discharge amount of the rolling oil is set to 35 L / s or less. The upper limit of the preferred rolling oil discharge rate is 30 L / s, and more preferably 25 L / s. The most desirable method for transferring the roughness of the roll is non-lubricated rolling at a rolling oil discharge rate of 0 L / s. In this case, the frictional resistance increases, and an increase in wear powder generated by processing is reduced. This may cause the surface cleanliness of the Fe—Ni-based alloy thin plate to deteriorate. Further, since the rolling is performed under severe conditions, there is a possibility that the surface of the rolling roll becomes rough, a heat crack or the like occurs. Therefore, when using rolling oil, the lower limit of the discharge amount of rolling oil is preferably set to 1 L / s. The lower limit of the preferred rolling oil discharge rate is 5 L / s, and more preferably 10 L / s.
The width of the Fe—Ni-based alloy thin plate is not particularly limited, but is preferably set to 1100 mm or less in order to maintain better surface cleanliness.

<Washing process>
In addition, in order to improve the surface cleanliness of the Fe—Ni-based alloy sheet, it is preferable to perform a cleaning step after performing the final cold finish rolling. This is because the adhesion also affects the cleanliness of the surface of the Fe—Ni-based alloy thin plate to be joined. In particular, in many cases, wear powder generated during processing or oil used during processing is attached to the surface of the Fe—Ni-based alloy thin plate that has been subjected to plastic processing. Since these foreign substances cause a factor to hinder the adhesion, it is preferable to carry out a cleaning step to further improve the adhesion. When performing the cleaning step, it is desirable to use a cleaning layer having a structure in which a hydrocarbon-based solvent, an alkaline solvent, or the like can be used while being sprayed or stirred. In addition, the cleaning liquid system is a circulating type with a device that filters the cleaning liquid containing foreign matter removed by cleaning with a filter, and by arranging a device to dry the material that comes out of the cleaning layer, continuous cleaning becomes possible. , Economical and high productivity can be maintained.

Next, an Fe-Ni-based alloy thin plate obtained by the above-described method for producing an Fe-Ni-based alloy thin plate of the present invention will be described.
<Surface roughness>
In the present invention, by setting the surface roughness of the obtained Fe—Ni-based alloy thin plate to Ra = 0.15 to 0.5 μm, the contact area with other members is increased, and the roughness formed on the plate surface is increased. The anchor effect can be enhanced and the adhesion can be dramatically improved.
When the surface roughness Ra is less than 0.15 μm, the contact area is reduced and the unevenness of the surface is also reduced, so that the adhesive force with the above-mentioned bonding material is reduced. Therefore, the surface roughness is set to Ra = 0.15 μm or more. Further, it is desirable that the surface roughness is higher from the viewpoint of adhesion. However, if the surface roughness is too rough, it becomes a factor that impairs the processing accuracy when performing high-definition etching. Therefore, the upper limit is set to 0.5 μm. Preferred surface roughness is 0.15 to 0.4 μm.

(Example 1)
Vacuum melting, soaking heat treatment, hot pressing and hot rolling were performed to prepare a hot-rolled material having a thickness of 3.0 mm. When the hardness of the hot-rolled material was measured, it was 170 to 190 HV. Table 1 shows the chemical composition of the hot-rolled material.
After that, the oxide layer on the surface of the hot-rolled material is removed by chemical polishing and mechanical polishing, rough rolling is performed, and cracks at both ends in the width direction of the material during hot rolling are removed by trimming, and cold rolling is performed. Materials were prepared.
Next, after the cold rolling and the continuous annealing were repeated twice each for the above-described material for cold pressing, the final cold finish rolling was performed under the conditions shown in Table 2, and the present invention examples (No. 1 to No. 1). 3) and Fe—Ni alloy thin plates of Comparative Examples (Nos. 11 and 12) were manufactured. The number of passes of the final cold finish rolling was one in both the present invention example and the comparative example, and the final thickness was 0.1 mm. The hardness before the final cold finish rolling is 135 HV, and the width is 800 mm. Table 2 shows the surface roughness (arithmetic mean roughness) of the obtained Fe—Ni-based alloy thin plates of the present invention examples (Nos. 1 to 3) and comparative examples (Nos. 11 and 12). FIG. 1 shows the correlation between the roll roughness used in the final cold finish rolling, which is important in the present invention, and the surface roughness of the Fe—Ni-based alloy sheet after the final cold finish rolling. In Table 2 and FIG. 1, the surface roughness of the Fe—Ni-based alloy thin plate is indicated as “material surface roughness”. The rolling roll roughness was measured using a contact-type portable roughness meter, and the material surface roughness was measured using a contact-type surface roughness meter to measure the length of 4 mm, and the arithmetic average roughness Ra was measured.

  From the results shown in Table 2 and FIG. 1, the rolling roll roughness used in the final cold finish rolling, which is important in the present invention, was Ra = 0.15 to 1.0 μm, which was higher than that of the comparative example. In Examples 1 to 4 (Examples of the present invention), it was confirmed that the surface roughness of the Fe—Ni-based alloy thin plate was in the range of Ra = 0.15 to 0.5 μm, which was higher than that of the comparative example. Further, in the example of the present invention, no. 1 and No. When No. 2 was compared, No. 2 in which the rolling speed was increased was used. In the case of No. 2, it can be confirmed that the Ra value of the surface roughness of the Fe—Ni-based alloy thin plate is reduced. No. No. 1 in which the discharge amount of the rolling oil was increased from No. 1. As for No. 4, It can be confirmed that the Ra value of the surface roughness of the Fe—Ni-based alloy thin plate is lower than that of No. 1. From this, it was confirmed that the Ra value of the surface roughness of the Fe—Ni-based alloy thin plate was reduced when the rolling speed was excessively high or when the discharge amount of the rolling oil was increased.

From the results described above, the adhesiveness is improved by increasing the surface roughness of the Fe—Ni-based alloy thin plate to Ra = 0.15 to 0.5 μm with respect to the present invention and the comparative example. The effect of whether or not was confirmed. In the confirmation of the effect, the rolling speed was the same condition. 1, No. 3, no. No. 12 was confirmed for its effect.
Regarding the evaluation of the adhesion, the adhesion to the curable resin was simply evaluated by a tensile test. In order to sufficiently exhibit the adhesion between the curable resin and the test piece, the test piece was immersed in a hydrocarbon solvent stirred in a washing tank, and then dried. The simple evaluation method and the evaluation result are shown below.

<Adhesion strength evaluation method by tensile test>
The evaluation of adhesion was performed according to the following procedure.
(1) A tensile test piece having a length of 200 mm, a chuck portion width of 35 mm, a parallel portion length of 75 mm, and a width of 12.5 mm was prepared from each condition (Nos. 1, 3, and 12).
(2) Shear cutting at the center in the length direction of the test piece.
(3) Wash the test piece.
(4) An epoxy resin and a curing agent were mixed and stirred at a ratio of 10: 1, and then applied to one end (an area of 12.5 mm in width × 12.5 mm in length) of one of the cut test pieces.
(5) The other test piece was overlapped and joined to the resin-coated portion (12.5 mm wide x 12.5 mm long). (FIGS. 2A and 2B)
(6) A load (0.4 g / mm ² ) was applied on the joined test pieces and held for 10 hours.
(7) A tensile test (initial load: 0.1 kN, speed: 2 mm / min) was performed on the test piece prepared by the above method, and the tensile strength was measured.
The adhesion was evaluated according to the above procedures (1) to (7). The test piece after the evaluation test result is shown in FIG. 2 (C), and the evaluation result is shown in Table 3.

From the evaluation results in Table 3, No. 3 to which the method of the present invention was applied. Nos. 1 and 3 are Comparative Examples Nos. 12, the allowable load per unit bonding area is improved about 1.4 to 2.2 times. Thus, according to the present invention, in a thin Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less, the surface roughness of the Fe-Ni-based alloy thin plate is made higher than before, and Ra = 0. It can be seen that by setting the thickness to 5 μm, the adhesion can be improved. This makes it possible to prevent poor adhesion between the Fe-Ni-based alloy thin plate and the counterpart material that adheres to the thin sheet.

Claims (2)

Ni + Co: 35.0 to 43.0% (however, Co is 0 to 6.0%) in mass%, Si: 0.5% or less, Mn: 1.0% or less, and the balance is Fe and impurities. The cold-rolling material includes a cold-rolling step in which cold-rolling and continuous annealing are performed at least once, and the final cold-finish rolling in the cold-rolling step is performed with a roll roll roughness Ra = 0. 0 μm, rolling speed 0.5-6.5 m / s , rolling oil kinematic viscosity 8-40 mm ² / s , rolling oil discharge amount 1-35 L / s , thickness 0.25 mm or less, surface roughness Is a method for producing an Fe—Ni-based alloy thin plate wherein Ra = 0.15 to 0.5 μm .   The method for producing an Fe-Ni-based alloy sheet according to claim 1, wherein the Fe-Ni-based alloy sheet is washed after the final cold finish rolling.