JP2019010753A - Ion-implanted copper alloy substrate, manufacturing method of the same, and copper-based die - Google Patents

Abstract

To provide an ion-implanted copper alloy substrate exhibiting a high hardness, excellent wear resistance, and an excellent releasing property, and a manufacturing method that enables obtaining the same.SOLUTION: According to a manufacturing method of an ion-implanted copper alloy substrate, comprising a step of implanting carbon ions into a portion made of a copper-based alloy in a substrate in which at least a part of the surface is formed of the copper-based alloy; the method comprises a step of implanting the carbon ions exceeding a dose of 10(ions/cm), while managing temperature of the substrate so as not to exceed 50°C.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ion-implanted copper alloy substrate, a method for producing the same, and a copper mold.

In injection molding and press molding for plastic and fiber reinforced plastic parts, rapid heating / cooling of molds is strongly required to shorten the molding time, and high thermal conductivity materials with good thermal conductivity are required. Attempted use.
Copper alloys such as brass (Cu-Zn), bronze (Cu-Sn), beryllium copper (Be-Cu) and Corson alloy (Cu-Ni-Si) are known as high thermal conductivity materials. . For example, the thermal conductivity of stainless steel is about 20 W / m · K, whereas the thermal conductivity of a Cu—Ni—Sn based copper alloy is about 150 W / m · K.

  As a conventional method related to this, for example, in Patent Document 1, since the copper-based alloy has high thermal conductivity, it has a high cooling effect when used in a casting mold, and has an effect of lowering the mold temperature. A molten material (molding material) comprising a nickel-based film having a porous layer made of a nickel alloy containing at least nitrogen, and a DLC-based film formed on the surface of the nickel-based film. ) Is said to have an effect of preventing seizure.

  According to Patent Document 2, a Cu-Ni-Si-based copper alloy material and a high-hardness metal material are interface bonded, and a diffusion layer of Ni and Si is formed at the bonding interface, thereby forming a high-hardness, high-heat conductive composite metal. It is stated that the material is obtained.

  However, in Non-Patent Document 1, Moldmax-HH (Brush Wellman), which is considered to be the hardest copper alloy, is at most about HRC40. In Non-Patent Document 1, glass fiber is generally added as a means of increasing the strength and heat resistance of plastic products. If glass fiber is contained as much as 30%, a copper alloy having a hardness of about HRC 40 will wear. It is stated that the decrease in mold life due to is obvious. In addition, as a countermeasure against wear, it is stated that the surface hardness has been increased not by ion implantation but by plating, ion coating, and other surface treatments.

Japanese Patent Laying-Open No. 2015-024625 Japanese Patent No. 5939590

Takashi Fukuda, Copper Alloy Mold Material, Vol, 53 (2012) No.9 SOKEIZAI 29-35

  An object of the present invention is to provide an ion-implanted copper alloy base material having high hardness, excellent wear resistance, and excellent releasability, a production method capable of obtaining the same, and a copper-based mold comprising the same. is there.

The inventor of the present application has studied means for increasing the hardness and improving the wear resistance with respect to the hardness which is a weak point of the copper-based alloy. And it confirmed that hardness and abrasion resistance improved by performing carbon ion implantation to copper system alloy. Furthermore, it was confirmed that the hardness and wear resistance were improved in proportion to the carbon ion implantation amount. It was also confirmed that the contact angle with the molten resin increased in proportion to the carbon ion implantation amount.
And it came to this invention.

The present invention includes the following (1) to (7).
(1) A method for producing an ion-implanted copper alloy base material comprising an operation of injecting carbon ions into a part made of a copper-based alloy in a base material made of a copper-based alloy at least part of the surface,
A method for producing an ion-implanted copper alloy base material, wherein the carbon ion is implanted in excess of 10 ¹⁷ doses (ions / cm ³ ) while controlling the temperature of the base material not to exceed 50 ° C.
(2) The method for producing an ion-implanted copper alloy substrate according to (1), wherein the copper-based alloy is a spinodal decomposition type copper alloy.
(3) The manufacturing method of the ion implantation copper alloy base material as described in said (1) or (2) from which the ion implantation copper alloy base material whose outermost layer surface hardness is HV470 or more is obtained.
(4) The manufacturing method of the ion implantation copper alloy base material in any one of said (1)-(3) with which the ion implantation copper alloy base material which is a metal mold | die used in order to shape | mold resin is obtained.
(5) The manufacturing method of the ion implantation copper alloy base material as described in said (4) whose said resin is cycloolefin polymer resin (COP resin).
(6) An ion-implanted copper alloy substrate obtained by the production method according to any one of (1) to (3) above.
(7) A copper mold comprising the ion-implanted copper alloy according to (6).

  According to the present invention, it is possible to provide an ion-implanted copper alloy base material having high hardness, excellent wear resistance, and excellent releasability, a production method capable of obtaining the same, and a copper-based mold comprising the same. it can.

  Such an ion-implanted copper alloy base material and a copper mold made thereof have a long life due to their high hardness. In addition, since heating and cooling can be performed quickly, the molding time can be shortened, and the use of a mold and repair over time can be facilitated.

6 is a schematic view of a carbon ion implantation apparatus used in Experiment 2. FIG. 6 is a graph showing measurement results of Vickers hardness in Experiment 2. 6 is a photograph of wear marks in the frictional wear test of Experiment 2. 6 is a photograph of a wear mark of a probe in the frictional wear test of Experiment 2. 6 is a graph showing transition of a static friction coefficient μs and a dynamic friction coefficient μk in a frictional wear test of Experiment 2. It is a graph which shows the value of arithmetic mean roughness (Ra) and the maximum height roughness (Rz) in the roughness measurement test of Experiment 2. It is another graph which shows the value of the arithmetic mean roughness (Ra) and the maximum height roughness (Rz) in the roughness measurement test of Experiment 2. It is a photograph of the polishing mark after the roughness measurement test of Experiment 2. It is a photograph which shows the mode of the COP resin pellet when the inside of the solid-liquid contact angle measuring apparatus reaches 260 degree | times in the wettability measurement test of Experiment 2. FIG. It is a graph which shows the contact angle measured in the wettability measurement test of Experiment 2. It is a graph which shows the relationship between a dose amount and a contact angle.

The production method of the present invention will be described.
The production method of the present invention is a method of producing an ion-implanted copper alloy base material, comprising an operation of injecting carbon ions into a part made of a copper-based alloy in a base material made of a copper-based alloy at least part of the surface. In the method of manufacturing an ion-implanted copper alloy base material, the carbon ions are implanted in excess of 10 ¹⁷ doses (ions / cm ³ ) while controlling the temperature of the base material not to exceed 50 ° C. is there.

In the production method of the present invention, a base material having at least a part of the surface made of a copper-based alloy is prepared.
A base material will not be specifically limited in a magnitude | size and a shape, if at least one part of the surface consists of a copper-type alloy. As will be described later, since the ion-implanted copper alloy substrate obtained by the production method of the present invention is preferably a mold, the substrate is preferably the same size and shape as the mold.

Since the base material only needs to have at least a part of its surface made of a copper-based alloy, for example, a part of the surface is made of a copper-based alloy and the remaining part of the surface is made of a material other than the copper-based alloy. It's okay. Further, for example, the portion that is not the surface, that is, the inside may be made of a material other than the copper-based alloy.
However, the substrate is preferably made of a copper-based alloy.

The copper-based alloy constituting at least a part of the substrate means an alloy containing copper (Cu). Copper alloys include brass (Cu-Zn), bronze (Cu-Sn), beryllium copper (Be-Cu), Corson alloy (Cu-Ni-Si), Cu-Ni-Sn, Cu -Spinodal decomposition type copper alloys, such as Ti system, are mentioned.
The copper-based alloy is preferably a Cu—Ni—Sn-based spinodal decomposition type copper alloy.
Cu-Ni-Sn spinodal decomposition type copper alloy is a general processing process of melt casting → homogenization → hot rolling → cold rolling 1 → solution treatment → cold rolling 2 → aging in aging It is a copper alloy that has undergone spinodal decomposition in the treatment and has undergone structure control, and the composition is, for example, Ni: 5 to 20 mass%, Sn: 5 to 10 mass%, and the balance consisting of Cu and inevitable impurities Can be mentioned. A method for producing a spinodal decomposition type copper alloy is described, for example, in JP-A-2009-242895.

  In the production method of the present invention, carbon ions in the base material as described above are implanted. Here, when a base material consists of a copper-type alloy, carbon ion is inject | poured into the arbitrary parts of the surface. Moreover, when a part of surface of a base material consists of a copper alloy, carbon ion is inject | poured into the part which consists of the copper alloy.

  The implantation of carbon ions is an operation in which ionized carbon is taken out as an ion beam to an electrode, kinetic energy is given by an accelerator, and the substrate is driven into a substrate, and can be performed using a conventionally known apparatus.

In the production method of the present invention, when carbon ions are implanted into the surface of the base material, the temperature of the base material is monitored and managed so that the temperature of the base material does not exceed 50 ° C.
Specifically, the temperature of the substrate is preferably measured constantly. However, it may be measured intermittently. When carbon ions are injected into the base material, the temperature of the base material rises. Therefore, if there is a possibility that the temperature exceeds 50 ° C., the carbon ion injection is temporarily stopped and the temperature is lowered to some extent, and then Resume injection. Alternatively, ion implantation is performed within a range in which the temperature does not rise sufficiently over time. Then, since the substrate temperature tends to decrease, after the substrate temperature has decreased to some extent, carbon ion implantation is resumed or the implantation amount is increased. That is, carbon ions are injected into the base material while intermittently injecting carbon ions into the base material or adjusting the carbon ion injection amount so that the temperature of the base material does not exceed 50 ° C. Ions are implanted in excess of 10 ¹⁷ doses (ions / cm ³ ).
The present inventor has intensively studied and found that when the temperature of the base material exceeds 50 ° C., an ion-implanted copper alloy base material having high hardness, excellent wear resistance, and excellent releasability cannot be obtained. It was. Similarly, even if the amount of carbon ions implanted into the substrate is 1 × 10 ¹⁷ doses (ions / cm ³ ) or less, the ion implantation is similarly high in hardness, excellent in wear resistance, and excellent in releasability. It has been found that a copper alloy base material cannot be obtained. Further, when the temperature of the substrate exceeds 50 ° C., the copper-based alloy softens when the copper-based alloy constituting at least a part of the substrate is a Cu—Ni—Sn-based spinodal decomposition type copper alloy. There is a possibility that it is not preferable. When the temperature of the base material during carbon ion implantation does not exceed 50 ° C. and the amount of carbon ions to be injected into the base material exceeds 1 × 10 ¹⁷ doses (ions / cm ³ ), the hardness is It was found that an ion-implanted copper alloy base material that is high, excellent in wear resistance, and excellent in releasability can be obtained.

  In the production method of the present invention, the temperature of the substrate is controlled so as not to exceed 50 ° C., but this temperature is preferably 50 ° C. or less. Moreover, it is preferable that it is 20 degreeC or more, and it is more preferable that it is 35 degreeC or more.

It is preferable that an ion-implanted copper alloy substrate having an outermost layer surface hardness of HV470 or more is obtained by the production method of the present invention. If the processing conditions are appropriate, such an ion-implanted copper alloy can be obtained.
In the present invention, the Vickers hardness (HV) is measured by a method defined in JIS Z 2244.

The ion-implanted copper alloy base material obtained by the production method of the present invention can be preferably used as a mold used for molding a cycloolefin polymer resin (COP resin). It is because it is rich in releasability.
Such a mold can be used for forming, for example, a light guide plate, a light guide, a microfluidic, a resin mold, a semiconductor container, a biochip, a bioplate, an infusion bag, and a multilayer film.

<Experiment 1>
A test piece made of a commercially available copper / nickel / tin based (Cu 77%, Ni 15%, Sn 8%) spinodal decomposition type copper alloy was prepared. The size of the test piece was 15 mm × 15 mm, the thickness was 2 mm, and the hardness was HRC30 (HV300).

Next, this test piece was subjected to plasma nitriding treatment under various conditions. For plasma nitriding treatment, trade name: PINK manufactured by Shin Meiwa Kogyo Co., Ltd. was used. Plasma nitriding conditions were performed within the following ranges.
Plasma current value: 40-75A
Bias voltage: 150-400V
Processing time: 90-180min
Ion current value: 0.53 to 1.06 mA / cm ²
Dose: 3.1-4.7 × 10 ¹⁷ ions / cm ²
Test piece temperature: 280-320 ° C

  The hardness of each of a plurality of test pieces obtained by performing plasma nitriding treatment under various conditions was measured. As a result, the hardness of all the test pieces was less than HRC30 (HV300). That is, the hardness of the test piece after the application was lower than that before the plasma nitriding process.

<Experiment 2>
Four test pieces made of a commercially available copper / nickel / tin-based (Cu 77%, Ni 15%, Sn 8%) spinodal decomposition type copper alloy were prepared. All the test pieces had a size of 15 mm × 15 mm, a thickness of 2 mm, and a hardness of HRC30 (HV300).

Next, carbon ion implantation was performed on these test pieces. The carbon ion implanter used here is an ion implanter II-100x550 manufactured by Shin Meiwa Kogyo Co., Ltd. An outline of this apparatus is shown in FIG. In FIG. 1, the vacuum chamber and the vacuum system are not shown.
Using methane gas as a carbon ion generation source, carbon ions were implanted under the four conditions No. # 1 to # 4 shown in Table 1. In addition, a commercially available Faraday cup was used for the measurement of carbon ion implantation amount (dose amount measurement). For No. # 3 and # 4, as a pretreatment for carbon ion implantation, cleaning was performed by irradiating the test piece with Ar ions.

<Hardness measurement>
Vickers hardness was measured for each of the test pieces obtained by carbon ion implantation under the four conditions No. # 1 to # 4 shown in Table 1. The Vickers hardness was measured using a dynamic ultra-micro hardness meter DUH-211 (manufactured by Shimadzu Corporation). The load holding time at the time of measurement was 10 sec. The measurement results are shown in FIG.

  As shown in FIG. 2, among No. # 1 to # 4 subjected to carbon ion implantation, the No. # 1 to # 3 hardness did not change greatly. It was confirmed that the Vickers hardness was remarkably increased.

<Friction and wear measurement>
Each of the test pieces obtained by carbon ion implantation under the four conditions No. # 1 to # 4 shown in Table 1 was subjected to a frictional wear test.
HEIDON-14D (manufactured by Shinto Kagaku Co., Ltd.) was used for the frictional wear test. Here, the test load was 100 g, and a 10 mm diameter copper ball was used as a measuring element. And the friction by a reciprocating motion was repeated and the state of the wear trace of a test piece and a measuring element was confirmed.
The number of reciprocations was 1000 for No. # 1 and # 4 that were untreated and implanted with carbon ion, and 200 for No. # 3. No. # 2 was not rubbed by reciprocating motion. The number of measurements was 3 for untreated carbon ion implantation and No. # 4, and 1 for No. # 1 and No. # 3.
FIG. 3 shows the wear trace of each test piece, and FIG. 4 shows the wear trace of the probe after the carbon ion implantation untreated and No. # 4 test.

From the results shown in FIG. 3, the size of the wear marks formed on the test piece after 1000 reciprocations was extremely small for No. # 4, then No. # 1, followed by untreated carbon ion implantation. Recognize. From this, it can be said that No. # 4 was not easily damaged by carbon ion implantation.
Further, from the results shown in FIG. 4, it can be seen that the wear scar formed on the probe after 1000 reciprocations is clear when carbon ion implantation is not performed, and the wear area is unclear in No. # 4. From this, it can be said that when the carbon ion implantation was not performed, both the test piece and the probe were worn, and in the case of No. # 4, neither was worn.

  FIG. 5 shows the transition of the static friction coefficient μs and the dynamic friction coefficient μk of carbon ion implantation untreated and No. # 4. From FIG. 5, it can be seen that μs and μk of No. # 4 after 1000 reciprocations are smaller than those of the untreated carbon ion implantation. This is considered that the slidability of the test piece (Cu—Ni—Sn spinodal decomposition type copper alloy) was improved by carbon ion implantation.

<Roughness measurement>
Surface roughness, arithmetic average roughness (Ra), and maximum height roughness for each of the test pieces obtained by carbon ion implantation under the four conditions No. # 1 to # 4 shown in Table 1 (Rz) was measured. These were performed using a 3D measurement laser microscope LEXT OLS4100 (manufactured by OLYMPUS) and a surface roughness measuring instrument PGI1240 (manufactured by Taylor-Hobson). The former is a non-contact type, and the latter is a contact type.
FIG. 6 shows the values of arithmetic average roughness (Ra) and maximum height roughness (Rz) measured by LEXT OLS4100.
From FIG. 6, in LEXT OLS4100, no clear difference was observed between the carbon ion implanted untreated specimens and the No. # 1 to # 4 specimens subjected to carbon ion implantation. That is, it could not be confirmed that the surface was roughened by carbon ion implantation.

FIG. 7 shows the measurement results of arithmetic average roughness (Ra) and maximum height roughness (Rz) measured with PGI1240. The measurement was performed at a measurement length of 7 mm and a feed rate of 0.5 mm / sec.
From FIG. 7, it can be seen that in PGI 1240, the values of Ra and Rz were lower in the test pieces of No. # 1 to # 4 subjected to carbon ion implantation than in the case where carbon ion implantation was not performed. It can be said that the polishing marks were removed by carbon ion implantation and the surface became smooth.
The results of the roughness measurement are summarized in Table 2.

FIGS. 8A to 8D show the measurement surfaces of the test pieces observed using the LEXT OLS4100 at a magnification of 50 times (objective lens: MPLAPONLEXT50).
In FIG. 8A, polishing marks are seen. Further, although fine cracks are confirmed in the test pieces of FIGS. 8B to 8E, the polishing marks are reduced.

<Measurement of wettability>
For each of the test pieces obtained by carbon ion implantation under the four conditions of No. # 1 to # 4 shown in Table 1, high temperature wettability / solid-liquid contact angle measuring device WET-1200 (Advanced Riko) Wetability test using cycloolefin polymer resin (COP resin) and ZEONOR 1420R (manufactured by Nippon Zeon Co., Ltd.) was conducted.
In the wettability test, pellet-shaped COP resin was prepared, and the contact angle at 260 ° C. was measured for each test piece of COP resin. 260 ° C. was determined in consideration of the fact that the melting temperature of the resin was 240 ° C. or higher and that the actual use temperature of the copper / nickel / tin spinodal decomposition type copper alloy was approximately 260 ° C. or lower. Therefore, when the contact angle measured by the measurement procedure shown below is large, it can be determined that the COP resin has high releasability with respect to the copper / nickel / tin spinodal decomposition type copper alloy. As will be described later, the contact angle is measured in a nitrogen atmosphere while the actual use atmosphere of the molding die is air. This is to evaluate the releasability from the basic resin on the metal surface after removing the influence of oxidation and carbonization. Although it is actually exposed to the atmosphere, the characteristics of the metal surface itself cannot be grasped due to the effects of oxidation and carbonization.
The contact angle measurement procedure is as follows.
[1] COP resin pellets and copper / nickel / tin spinodal decomposition copper alloy specimens were previously dried at 80 ° C. for 12 hours or more. AVO-250N (As One Co., Ltd.) was used as the vacuum dryer, and DAU-20 (ULVAC, Inc.) was used as the vacuum pump.
[2] The test piece was loaded into an infrared heating furnace, COP resin pellets were placed on the surface, and the temperature was raised from 20 ° C. (normal temperature) to 260 ° C. in 3 minutes and 52 seconds in a nitrogen atmosphere.
[3] After reaching 260 ° C., this temperature was maintained and the contact angle was measured after 1 minute. Based on the measurement results, the contact angle was calculated according to JIS R 3257 “Test method for wettability of substrate glass surface”.
For comparison, a similar test was performed on a test piece into which carbon ions were not implanted. FIG. 9 shows a photograph showing the state of the COP resin pellet when the inside of the solid-liquid contact angle measuring apparatus reaches 260 degrees.
FIG. 10 shows the contact angle when each test piece is used. FIG. 10 also shows the contact angle value calculated by the software.

  From these results, it was found that the No. # 4 test piece with the largest dose amount had the highest contact angle, and the contact angle increased in proportion to the dose amount. The contact angle of No. # 4 specimen subjected to carbon ion implantation is excellent in releasability from COP resin and is comparable to that of stainless steel mold. FIG. 11 is a graph showing the relationship between the dose and the contact angle.

Claims (7)

A method for producing an ion-implanted copper alloy base material comprising an operation of injecting carbon ions into a part made of a copper-based alloy in a base material made of a copper-based alloy at least part of the surface,
A method for producing an ion-implanted copper alloy base material, wherein the carbon ion is implanted in excess of 10 ¹⁷ doses (ions / cm ³ ) while controlling the temperature of the base material not to exceed 50 ° C.   The manufacturing method of the ion implantation copper alloy base material of Claim 1 whose said copper-type alloy is a spinodal decomposition type | mold copper alloy.   The manufacturing method of the ion implantation copper alloy base material of Claim 1 or 2 with which the ion implantation copper alloy base material whose outermost layer surface hardness is HV470 or more is obtained.   The manufacturing method of the ion implantation copper alloy base material in any one of Claims 1-3 with which the ion implantation copper alloy base material which is a metal mold | die used in order to shape | mold resin is obtained.   The manufacturing method of the ion implantation copper alloy base material of Claim 4 whose said resin is cycloolefin polymer resin (COP resin).   The ion implantation copper alloy base material obtained by the manufacturing method in any one of Claims 1-3.   A copper mold comprising the ion-implanted copper alloy according to claim 6.