CN103547692A - Cu-Ni-Si copper alloy sheet with excellent deep drawability and process for producing same - Google Patents

Abstract

A Cu-Ni-Si copper alloy sheet which contains 1.0-3.0 mass% Ni and contains Si in a concentration by mass% that is 1/6 to 1/4 the Ni concentration, with the remainder comprising Cu and incidental impurities, and in which the surface has an arithmetic average roughness Ra of 0.2 [mu]m, the standard deviation of the absolute values for the crests and troughs from the surface-roughness mean line as a reference is 0.1 [mu]m or less, and the crystal grains in the alloy structure have an aspect ratio of 0.4-0.6 on average. When all pixels present in the field of view are examined for orientation by the EBSD method and each boundary between adjoining pixels that differ in orientation by 5 degree or larger is taken as grain boundary, then the average GOS of all the crystal grains is 1.2-1.5 degree and the ratio of the total length Ls of all special boundaries to the total length L of all grain boundaries (Ls/L) is 60-70%. The copper alloy sheet has a spring limit of 450-600 N/mm2, has satisfactory high-temperature solder adhesion when examined at 150 DEG C for 1,000 hours, fluctuates little in fatigue resistance, and has excellent deep drawability.

Description

Cu-Ni-Si series copper alloy plate and the manufacture method thereof of deep drawing excellent in workability

Technical field

The present invention relates to a kind of Cu-Ni-Si series copper alloy plate and manufacture method thereof, this Cu-Ni-Si series copper alloy plate can maintain the balance between deep drawing processibility, solder heat resistance separability and elastic limit value, the change of resistent fatigue characteristic is few, especially there is excellent deep drawing processibility, be adapted at using in electrical and electronic parts.

The application requires right of priority on the basis of the International Application PCT/JP2011/062028 of proposition on May 25th, 2011, and here cites its content.

Background technology

Compactization along with electronics in recent years, terminal and junctor etc. are also to miniaturization and thin-walled property future development, and be required intensity and bendability, thereby replace the solution strengthening type copper alloys such as phosphor bronze in the past or brass, the demand of the precipitation strength type copper alloy that section gloomy (Cu-Ni-Si system) alloy, beryllium copper, titanium copper are so increases.

Wherein, Corson alloy is nickel silicide Compound Phase for the solid solution limit of copper according to the alloy of temperature noticeable change, and be a kind of curing alloy of separating out being cured by quenching and tempering, its thermotolerance and hot strength are also good, the balance of intensity and electric conductivity is also excellent, thereby in conduction, with various springs and high-tensile, with on electric wire etc., be widely used so far, the frequency of using on the electronic units such as terminal and junctor in recent years increases day by day.

In general, intensity and bendability are contrary character, for Corson alloy also research always, can maintain the high-intensity scheme of simultaneously improving bendability, and extensively carry out by adjusting manufacturing process and controlling respectively or mutually control the quantity of crystal particle diameter, precipitate and shape and texture are improved the scheme of bendability.

In addition, for Corson alloy is used in to various electronic units with the shape of stipulating under harsh environment, the solder heat resistance separability while requiring there is ease of processing, particularly good deep drawing processibility and at high temperature use.

Patent documentation 1 discloses 1/6～1/4 the Si that a kind of Ni that comprises 1.0～4.0 quality % and concentration are Ni concentration, and the electronic component-use Cu-Ni-Si of the balance excellence of the frequency of the twin boundary in all grain boundaries (the Σ 3 borders) intensity that is 15～60% and bendability is base alloy.

Patent documentation 2 discloses following a kind of copper-based deposited alloy board, this copper-based deposited alloy board is copper-based deposited alloy board for contact material, the tensile strength of its rolling direction, the angle forming with rolling direction is the tensile strength of 45 ° of directions, the angle forming with rolling direction is that each poor maximum value each other of these three tensile strength of tensile strength of 90 ° of directions is below 100MPa, the Si of the Ni that contains 2～4 quality % and 0.4～1 quality %, further contain if desired the appropriate Mg that is selected from, Sn, at least one in Zn and Cr, and surplus is copper and inevitable impurity.This copper-based deposited alloy board for contact material is implemented timeliness thermal treatment to the copper alloy plate of solution treatment, then implements cold rolling below 30% of rolling rate and manufactures, and it improves the operability of the multifunction switch using in electronics etc.

It is 700N/mm that patent documentation 3 discloses a kind of yield strength ²above, electric conductivity is also excellent section gloomy (Cu-N-Si system) copper alloy plate of the above and bendability of 35%IACS.This copper alloy plate becomes 4～5 scope mode with the mass ratio Ni/Si of Ni and Si comprises 2.5%(quality %, identical below) above and lower than 6.0% Ni and 0.5% above and lower than 1.5% Si, further comprise more than 0.01% and lower than 4% Sn, surplus is Cu and inevitable impurity, average crystalline particle diameter is below 10 μ m, { ratio of 001}<100> is more than 50% texture in the measurement result based on SEM-EBSP method, to have cubes (Cube) orientation, and it is manufactured by following steps: by continuous annealing, obtaining after solid solution and recrystallize treatment tissue, carry out the ageing treatment of cold rolling below 20% of working modulus and 400～600 ℃ * 1～8 hour, then after carrying out working modulus 1～20% final cold rolling, carry out following short-cycle annealing in 400～550 ℃ * 30 seconds.

Patent documentation 1: Japanese Patent Publication 2009-263784 communique

Patent documentation 2: Japanese Patent Publication 2008-95186 communique

Patent documentation 3: Japanese Patent Publication 2006-283059 communique

Cu-Ni-Si is in the past that the deep drawing processibility of Corson alloy is also insufficient; and the balanced differences between deep drawing processibility, solder heat resistance separability and elastic limit value; and the change of resistent fatigue characteristic (deviation) is large, usually can gives as the application that is exposed to for a long time the electronic part material under harsh environment for use in high temperature and high vibration and bring obstacle.

Summary of the invention

The present invention proposes in light of this situation, a kind of Cu-Ni-Si series copper alloy plate and manufacture method thereof are provided, this Cu-Ni-Si series copper alloy plate can maintain the balance between deep drawing processibility, solder heat resistance separability and elastic limit value, the change of resistent fatigue characteristic (deviation) is few, especially has excellent deep drawing processibility and uses at electrical and electronic parts.

What the inventor furtherd investigate found that, at the Ni that contains 1.0～3.0 quality %, and contain concentration and be 1/6～1/4 Si of the quality % concentration of Ni, surplus is in the Cu-Ni-Si series copper alloy plate of Cu and inevitable impurity, the arithmetic average roughness Ra on surface is 0.02～0.2 μ m, take the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark below 0.1 μ m, the mean value of the aspect ratio of crystal grain in alloy structure (crystal grain minor axis/crystal grain major diameter) is 0.4～0.6, mean value in all crystal grains of the GOS measuring according to the EBSD method of using the scanning electronic microscope of having electronic back scattering diffraction picture system is 1.2～1.5 °, when the special grain boundary total length L σ of special grain boundary is 60～70% with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, elastic limit value is 450～600N/mm ², the solder heat resistance separability under 150 ℃ and 1000 hours is good, and the change of resistent fatigue characteristic (deviation) is few, and deep drawing processibility is also brought into play excellent characteristic.

Further find, the solder heat resistance separability of the mean value major effect of the aspect ratio of crystal grain (crystal grain minor axis/crystal grain major diameter) under 150 ℃ and 1000 hours, mean value major effect elastic limit value in all crystal grains of GOS, ratio (L σ/L) the major effect deep drawing processibility of the special grain boundary total length L σ of special grain boundary, the arithmetic average roughness Ra on surface and the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark of take affect the change (deviation) of resistent fatigue characteristic.

Also find in addition, the mean value of the aspect ratio of crystal grain (crystal grain minor axis/crystal grain major diameter) depends basically on and in manufacture, carries out final working modulus when cold rolling, mean value in all crystal grains of GOS depends basically on copper alloy plate while carrying out continuous low temperature annealing in the manufacture tension force in stove, the ratio (L σ/L) of the special grain boundary total length L σ of special grain boundary depends basically on copper alloy plate while carrying out continuous low temperature annealing in the manufacture floating distance in stove, the arithmetic average roughness Ra on surface and the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark of take depend basically on and in manufacture, carry out the final tension force of copper alloy plate being given when cold rolling and the surfaceness of roll.

The present invention is that the understanding based on above-mentioned is made, Cu-Ni-Si series copper alloy plate of the present invention is characterised in that, the Ni that contains 1.0～3.0 quality %, and contain concentration and be 1/6～1/4 Si of the quality % concentration of Ni, surplus is Cu and inevitable impurity, the arithmetic average roughness Ra on surface is 0.02～0.2 μ m, take the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark below 0.1 μ m, the mean value of the aspect ratio of crystal grain in alloy structure (crystal grain minor axis/crystal grain major diameter) is 0.4～0.6, when measuring measuring the orientation of all pixels in areal extent according to the EBSD method of the scanning electronic microscope of use having electronic back scattering diffraction picture system, and be that 5 ° of above borders are considered as in the situation of crystal boundary by the misorientation between neighbor, mean value in all crystal grains of GOS is 1.2～1.5 °, the special grain boundary total length L σ of special grain boundary is 60～70% with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, elastic limit value is 450～600N/mm ², the solder heat resistance separability under 150 ℃ and 1000 hours is good, and the change of resistent fatigue characteristic is few, has excellent deep drawing processibility.

Ni and Si, by carrying out suitable thermal treatment, form with Ni ₂si is the minuteness particle of master's intermetallic compound.Its result, alloy strength significantly increases, and has also improved electroconductibility simultaneously.

Ni, with 1.0～3.0 quality %, preferably adds with the scope of 1.5～2.5 quality %.When Ni is during lower than 1.0 quality %, can not obtain sufficient intensity.When Ni surpasses 3.0 quality %, in hot rolling, can crack.

1/6～1/4 of the interpolation concentration (quality %) that the interpolation concentration (quality %) of Si is Ni.When the interpolation concentration of Si be less than Ni add concentration 1/6 time, intensity can decline, when more than Ni, add concentration 1/4 time, not only unhelpful to intensity, and can reduce electroconductibility due to superfluous Si.

When the mean value of the aspect ratio (crystal grain minor axis/crystal grain major diameter) of crystal grain is less than 0.4 or while surpassing 0.6, can cause the decline of the solder heat resistance separability under 150 ℃ * 1000 hours.

Mean value in all crystal grains of GOS is less than 1.2 ° or while surpassing 1.5 °, can cause the decline of elastic limit value.

When the ratio (L σ/L) of the special grain boundary total length L σ of special grain boundary is lower than 60% or while surpassing 70%, can cause the decline of deep drawing processibility.

When surperficial arithmetic average roughness Ra surpasses 0.2 μ m, the change of resistent fatigue characteristic can become greatly, and when arithmetic average roughness Ra is during lower than 0.02 μ m, effect can be saturated, wastes manufacturing cost.

When take surfaceness average line while the standard deviation of the absolute value of each peak portion value and paddy portion value being surpassed to 0.1 μ m during as benchmark, it is large that the change of resistent fatigue characteristic can become.Although standard deviation is the smaller the better, consider manufacturing cost and effect, more than being preferably 0.03 μ m.

In addition, Cu-Ni-Si series copper alloy plate of the present invention is characterised in that, further contains the Sn of 0.2～0.8 quality % and the Zn of 0.3～1.5 quality %.

Sn and Zn have the intensity of improvement and stable on heating effect, especially Sn have the effect that improves proof stress relaxation property, and Zn has the stable on heating effect of the welding of improvement.Sn is to be added in 0.2～0.8 quality %, the scope of Zn with 0.3～1.5 quality %.When lower than aforementioned range, can not obtain desired effect, when surpassing aforementioned range, can cause the decline of electroconductibility.

In addition, Cu-Ni-Si series copper alloy plate of the present invention is characterised in that, further contains the Mg of 0.001～0.2 quality %.

Mg has the effect of improving stress relaxation characteristics and hot workability, when surpassing 0.2 quality %, can reduce castibility (decline of cast(ing) surface quality), hot workability and the heat-resisting separability of plating.

In addition, Cu-Ni-Si series copper alloy plate of the present invention is characterised in that, further contains one or more in Fe:0.007～0.25 quality %, P:0.001～0.2 quality %, C:0.0001～0.001 quality %, Cr:0.001～0.3 quality %, Zr:0.001～0.3 quality %.

Fe has the effect (suppressing the effect that surface crack and raw edges produce) by improving hot rolling and improves the effect that the effect etc. of the heat-resisting adaptation of plating improves junctor reliability, the heat-resisting adaptation of described plating is separated out the compound of Ni and Si to become miniaturization to improve, but when its content is lower than 0.007% time, above-mentioned effect can not obtain desired effect, on the other hand, when its content surpasses 0.25%, hot rolling effect is saturated, there will be on the contrary downtrending, and also can bring detrimentally affect to electroconductibility, therefore its content is set in to 0.007～0.25%.

P has the flexibility decrease that inhibition causes because of bending machining, thereby the effect of the plug characteristic of the junctor that raising obtains through forming process and the effect that improves resistance to migrate attribute (イ of resistance to マ グ レ ー シ ョ Application characteristic), but when its content is lower than 0.001% time, can not obtain desired effect, on the other hand, when its content surpasses 0.2%, significantly damage solder heat resistance separability, therefore its content is set in to 0.001～0.2%.

C has the effect that improves punching processing, also there is the effect by making the compound miniaturization of Ni and Si improve alloy strength, but when its content is lower than 0.0001% time, can not obtain desired effect, on the other hand, when content surpasses 0.001%, hot workability is brought to detrimentally affect, therefore not preferred.Therefore C content is set in 0.0001～0.001%.

Avidity between Cr and Zr and C is strong, easily make C be included in Cu alloy, in addition also there is the effect that further makes the compound miniaturization of Ni and Si and improve alloy strength, and further propose high-intensity effect by separating out of himself, but the content of one or both in Cr and Zr is lower than 0.001% time, the intensity that can not obtain alloy improves effect, on the other hand, when surpassing 0.3% containing sometimes, can generate the larger precipitate of Cr and/or Zr, the variation that causes thus plating, punching processing also can variation, and and then can damage hot workability, therefore not preferred.Therefore, the content of one or both in Cr and Zr is set in 0.001～0.3%.

And, the manufacture method of Cu-Ni-Si series copper alloy plate of the present invention is characterised in that, when comprising successively hot rolling, cold rolling, solution treatment, ageing treatment, final cold rolling and stress relief annealed technique manufactured copper alloy sheets, the working modulus 10～30%, the tension force that copper alloy plate is given are 90～150N/mm ², and use and under the condition of the roll that the grinding stone be #180～600 by granularity grinds, to implement finally cold rollingly, and the tension force that copper alloy plate is given in to stove is 300～900N/mm ², the floating distance of copper alloy plate is to implement continuous low temperature annealing under the condition of 10～20mm in stove.

When final working modulus when cold rolling is lower than 10% or while surpassing 30%, the mean value of the aspect ratio of crystal grain (crystal grain minor axis/crystal grain major diameter) can not fall in 0.4～0.6 scope.

The stove internal tension of when continuous low temperature is annealed, copper alloy plate being given is less than 300N/mm ²or surpass 900N/mm ²time, the mean value in all crystal grains of GOS can not fall within the scope of 1.2 °～1.5 °.

When in the stove of the copper alloy plate when continuous low temperature is annealed, floating distance is less than 10mm or surpasses 20mm, the special grain boundary total length L σ of special grain boundary can not fall in 60～70% scopes with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary.

When the final tension force of copper alloy plate being given when cold rolling is less than 90N/mm ²time, in the time of can causing take surfaceness average line as benchmark, the standard deviation of the absolute value of each peak portion value and paddy portion value surpasses 0.1 μ m, when tension force surpasses 150N/mm ²time, effect can be saturated, waste manufacturing cost.

When final, use when cold rolling while being less than by granularity the roll that the grinding stone of #180 grinds, the arithmetic average roughness Ra on surface can surpass 0.2 μ m, and when granularity surpasses #600, effect can be saturated and be difficult to the surface damage that removal produces in manufacturing process.

By the present invention, a kind of balance that can maintain between deep drawing processibility, solder heat resistance separability and elastic limit value is provided, the change of resistent fatigue characteristic is few, especially has Cu-Ni-Si series copper alloy plate and the manufacture method thereof used in electrical and electronic parts of excellent deep drawing processibility.

Accompanying drawing explanation

Fig. 1 is the schematic diagram that is illustrated in an example of the continuous low temperature annealing device using in the manufacture method of Cu-Ni-Si series copper alloy plate of the present invention.

Fig. 2 is for illustrating the schematic diagram of the copper coin floating distance in the continuous low temperature annealing furnace using in the manufacture method of Cu-Ni-Si series copper alloy plate of the present invention.

Embodiment

Below, embodiments of the present invention are described.

[one-tenth of copper alloy bar is grouped into]

Copper alloy web of the present invention has following composition: in quality %, and the Ni that contains 1.0～3.0 quality %, and contain 1/6～1/4 the Si that concentration is the quality % concentration of Ni, surplus is Cu and inevitable impurity.

Ni and Si, by implementing suitable thermal treatment, form with Ni ₂si is the minuteness particle of master's intermetallic compound.Its result, significantly increases alloy strength, also improves electroconductibility simultaneously.

Ni is with 1.0～3.0 quality %, and preferably the scope with 1.5～2.5 quality % is added.When Ni can not obtain sufficient intensity during lower than 1.0 quality %.When surpassing 3.0 quality %, Ni can crack in hot rolling.

1/6～1/4 of the interpolation concentration (quality %) that the interpolation concentration (quality %) of Si is Ni.When the interpolation concentration of Si be less than Ni add concentration 1/6 time, intensity can reduce, when more than Ni, add concentration 1/4 time, not only unhelpful to intensity, and can reduce electroconductibility due to superfluous Si.

In addition, this copper alloy, with respect to above-mentioned essentially consist, can further contain the Sn of 0.2～0.8 quality % and the Zn of 0.3～1.5 quality %.

Sn and Zn have the intensity of improvement and stable on heating effect, and Sn has the effect that improves proof stress relaxation property in addition, and Zn has the stable on heating effect of the welding of improvement.Sn is to be added in 0.2～0.8 quality %, the scope of Zn with 0.3～1.5 quality %.When lower than aforementioned range, can not obtain desired effect, when surpassing aforementioned range, can reduce electroconductibility.

In addition, this copper alloy, with respect to above-mentioned essentially consist, can further contain the Mg of 0.001～0.2 quality %.

Mg has the effect of improving stress relaxation characteristics and hot workability, in the scope of 0.001～0.2 quality %, adds.When surpassing 0.2 quality %, can reduce castibility (decline of cast(ing) surface quality), hot workability and the heat-resisting separability of plating.

In addition, this copper alloy is with respect to above-mentioned essentially consist, can further contain one or more in Fe:0.007～0.25 quality %, P:0.001～0.2 quality %, C:0.0001～0.001 quality %, Cr:0.001～0.3 quality %, Zr:0.001～0.3 quality %.

Fe has the effect (suppressing the effect that surface crack and raw edges produce) by improving hot rolling and improves the effect that the effect etc. of the heat-resisting adaptation of plating improves junctor reliability, the heat-resisting adaptation of described plating is separated out the compound of Ni and Si to become miniaturization to improve, but when its content is lower than 0.007% time, above-mentioned effect can not obtain desired effect, on the other hand, when its content surpasses 0.25%, hot rolling effect is saturated, there will be on the contrary downtrending, and also can bring detrimentally affect to electroconductibility, therefore its content is set in to 0.007～0.25%.

P has the flexibility decrease that inhibition causes because of bending machining, thereby the effect of the plug characteristic of the junctor that raising obtains through forming process and the effect that improves resistance to migrate attribute, but when its content is lower than 0.001% time, can not obtain desired effect, on the other hand, when its content surpasses 0.2%, significantly damage solder heat resistance separability, therefore its content is set in to 0.001～0.2%.

C has the effect that improves punching processing, also there is the effect by making the compound miniaturization of Ni and Si improve alloy strength, but when its content is lower than 0.0001% time, can not obtain desired effect, on the other hand, when content surpasses 0.001%, hot workability is brought to detrimentally affect, therefore not preferred.Therefore C content is set in 0.0001～0.001%.

Avidity between Cr and Zr and C is strong, easily make C be included in Cu alloy, in addition also there is the effect that further makes the compound miniaturization of Ni and Si and improve alloy strength, and further propose high-intensity effect by separating out of himself, but the content of one or both in Cr and Zr is lower than 0.001% time, the intensity that can not obtain alloy improves effect, on the other hand, when surpassing 0.3% containing sometimes, can generate the larger precipitate of Cr and/or Zr, the variation that causes thus plating, punching processing is variation also, and and then can damage hot workability, therefore not preferred.Therefore, the content of one or both in Cr and Zr is set in 0.001～0.3%.

And, the surperficial arithmetic average roughness Ra of this Cu-Ni-Si series copper alloy strip is 0.02～0.2 μ m, take the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark below 0.1 μ m, the mean value of the aspect ratio of crystal grain in alloy structure (crystal grain minor axis/crystal grain major diameter) is 0.4～0.6, when measuring measuring the orientation of all pixels in areal extent according to the EBSD method of the scanning electronic microscope of use having electronic back scattering diffraction picture system, and the misorientation between neighbor is that 5 ° of above borders are in the situation of crystal boundary, mean value in all crystal grains of GOS is 1.2～1.5 °, the special grain boundary total length L σ of special grain boundary is 60～70% with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, elastic limit value is 450～600N/mm ², the solder heat resistance separability under 150 ℃ and 1000 hours is good, and the change of resistent fatigue characteristic is few, has excellent deep drawing processibility.

[arithmetic average roughness Ra, the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark of take]

The arithmetic average roughness Ra on copper alloy plate surface tries to achieve as follows.

Adopt the contact pin type surface roughness instruments (SE-30D) of the little slope institute system of Co., Ltd., according to JIS B0651-1996, obtain distribution plan, and calculate arithmetic average roughness (Ra) (JIS B0601-1994) based on this distribution plan.

The standard deviation of absolute value of each peak portion value during as benchmark of the surfaceness average line on copper alloy plate surface and paddy portion value of take is tried to achieve as follows.

Adopt the contact pin type surface roughness instruments (SE-30D) of the little slope institute system of Co., Ltd., according to JIS B0651-1996, obtain distribution plan, and each peak portion value during as benchmark of surfaceness average line and the absolute value of paddy portion value are take in actual measurement based on this distribution plan, and calculate its standard deviation.

[aspect ratio, GOS, L σ/L]

The mean value of the aspect ratio of crystal grain in alloy structure (crystal grain minor axis/crystal grain major diameter) is tried to achieve as follows.

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi (the Ha イ テ of Hitachi Network ノ ロ ジー ズ society) system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of 1 hour, the sample after watering is carried out to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area (rolling direction) 150 μ m * 150 μ m.

Next, step-length with 0.5 μ m is measured measuring the orientation of all pixels in area, and be that 5 ° of above boundary definitions are crystal boundary by the misorientation between pixel, the set of two above pixels of being surrounded by crystal boundary is regarded as in the situation of crystal grain, the length of the long axis direction of each crystal grain is made as to a, the length of short-axis direction is made as to b, described b is defined as to aspect ratio divided by the value of described a, obtain the aspect ratio of measuring all crystal grains in area, and calculate its mean value.

When the mean value of the aspect ratio (crystal grain minor axis/crystal grain major diameter) of crystal grain is less than 0.4 or while surpassing 0.6, can cause the decline of the solder heat resistance separability under 150 ℃ * 1000 hours.

Mean value in all crystal grains of the GOS measuring according to the EBSD method that adopts the scanning electronic microscope of having electronic back scattering diffraction picture system, tries to achieve as follows.

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of 1 hour, the sample after watering is carried out to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area 150 μ m * 150 μ m.

Result according to the observation, obtains the poor mean value of average orientation between all pixels in the crystal grain of all crystal grains under the following conditions.

Step-length with 0.5 μ m is measured measuring the orientation of all pixels in areal extent, and is that crystal boundary is regarded on 5 ° of above borders as by the misorientation between neighbor.

Next, for all crystal grains being surrounded by crystal boundary, through type (1) calculates the mean value (GOS:Grain Orientation Spread) of the misorientation between all pixels in crystal grain respectively, and the average orientation between all pixels in the crystal grain of all crystal grains is poor using the mean value of its all values, i.e. mean value in all crystal grains of GOS.In addition, by the crystal grain that is made as of two above pixels connections.

$\mathrm{GOS}=\frac{\underset{i,j=1}{\overset{n}{\mathrm{\&Sigma;}}}{\mathrm{\&alpha;}}_{\mathrm{ij}(i\&NotEqual;j)}}{n(n-1)}...\left(1\right)$

In above formula, i, j represent the pixel number in crystal grain.

N represents the pixel quantity in crystal grain.

α _ijthe misorientation that represents pixel i and j.

Mean value in all crystal grains of GOS is less than 1.2 ° or while surpassing 1.5 °, can cause the decline of elastic limit value.

The special grain boundary total length L σ of the special grain boundary of measuring according to the EBSD method that adopts the scanning electronic microscope of having electronic back scattering diffraction picture system, with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, tries to achieve as follows.Special grain boundary is according to theoretical (the Krongerg et.al.:Trans.Met.Soc.AIME of CSL in crystallography, 185,501 (1949)) the Σ value of definition has the crystal boundary (coincidence lattice grain boundary) of 3 ≦ Σ≤29, is defined in this crystal boundary intrinsic corresponding position grid and is orientated defect Dq and meets Dq≤15 °/Σ ^1/2the crystal boundary of (D.G.Brandon:Acta.Metallurgica.Vol.14, p1479,1966).

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of 1 hour, the sample after watering is carried out to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area 150 μ m * 150 μ m.

Step-length with 0.5 μ m is measured measuring the orientation of all pixels in areal extent, and is that crystal boundary is regarded on 5 ° of above borders as by the misorientation between neighbor.

Next, crystal boundary total length L to the crystal boundary in measurement range is measured, and determine that the interface of adjacent crystal grain forms the position of the crystal boundary of special grain boundary, and obtain the crystal boundary length ratio L σ/L of the crystal boundary total length L of the special grain boundary total length L σ of special grain boundary and the crystal boundary of said determination, using it as special grain boundary length ratio.

When the ratio (L σ/L) of the special grain boundary total length L σ of special grain boundary is lower than 60% or while surpassing 70%, can cause the decline of deep drawing processibility.

[manufacture method]

The manufacture method of Cu-Ni-Si series copper alloy of the present invention is characterised in that, when comprising successively hot rolling, cold rolling, solution treatment, ageing treatment, final cold rolling and stress relief annealed technique manufactured copper alloy sheets, the working modulus 10～30%, the tension force that copper alloy plate is given are 90～150N/mm ², and use and under the condition of the roll that the grinding stone be #180～600 by granularity grinds, to implement finally cold rollingly, and the tension force that copper alloy plate is given in to stove is 300～900N/mm ², the floating distance of copper alloy plate is to implement continuous low temperature annealing under the condition of 10～20mm in stove.

When final working modulus when cold rolling is lower than 10% or while surpassing 30%, the mean value of the aspect ratio of crystal grain (crystal grain minor axis/crystal grain major diameter) can not fall in 0.4～0.6 scope, can cause the decline of solder heat resistance separability.

The stove internal tension of when continuous low temperature is annealed, copper alloy plate being given is less than 300N/mm ²or surpass 900N/mm ²time, the mean value in all crystal grains of GOS can not fall within the scope of 1.2 °～1.5 °, can cause the decline of elastic limit value.

When the floating distance of the copper alloy plate when continuous low temperature is annealed in stove is less than 10mm or surpasses 20mm, the special grain boundary total length L σ of special grain boundary can not fall in 60～70% scopes with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, can cause the decline of deep drawing processibility.

When the final tension force of copper alloy plate being given when cold rolling is less than 90N/mm ²time, in the time of can causing take surfaceness average line as benchmark, the standard deviation of the absolute value of each peak portion value and paddy portion value surpasses 0.1 μ m, when tension force surpasses 150N/mm ²time, effect can be saturated, waste manufacturing cost.

When final, use when cold rolling while being less than by granularity the roll that the grinding stone of #180 grinds, the arithmetic average roughness Ra on surface can surpass 0.2 μ m, and when granularity surpasses #600, effect can be saturated and be difficult to the surface damage that removal produces in manufacturing process.

One example of the continuous low temperature annealing device using in manufacture method of the present invention shown in Figure 1.Implement the final cold rolling copper alloy plate F that is wrapped in Abrollhaspel 11 and by tenslator 12 and tenslator 14, be applied in the tension force of regulation, and in Horizental annealer 13 with the temperature and time of regulation by low-temperature annealing, via grinding, pickler 15 is wound in pulling reel 16.

The distance that floats in the stove of the copper alloy plate F when continuous low temperature is annealed in the present invention as shown in Figure 2, is by the fluctuate wave height value of the copper alloy plate F that advances of the hot blast G in stove.In Fig. 2, copper alloy plate F fluctuates with the ripple of span L, and the height of taking from Gai Bo center is called to floating distance H.This floating distance H can be by by 12,14 pairs of tension force that copper alloy plate F applies of tenslator with control at the spray volume of the interior hot blast G that copper alloy plate F is blowed of annealing furnace 13.

As an example of concrete manufacture method, can enumerate following method.

First, allotment material, makes it to become Cu-Ni-Si series copper alloy plate of the present invention, adopts the Low-frequency Flowing Furnace of reducing atmosphere to melt casting, obtains copper alloy casting ingot.Next, this copper alloy casting ingot is heated to after 900～980 ℃, implements hot rolling, make it to become the hot-rolled sheet of suitable thickness, after this hot-rolled sheet is carried out to water-cooled, suitable building up by welding is carried out in two sides.Next, with 60～90% rolling rate, implement cold rollingly, after making the cold-reduced sheet of suitable thickness, under the maintenance condition of 710～750 ℃ and 7～15 seconds, implement continuous annealing.Next, to completing after this copper coin that continuous annealing processes carries out pickling and surface grinding, the rolling rate with 60～90% is implemented cold rolling, makes the cold rolled sheet of suitable thickness.Next, after this cold rolled sheet is maintained to 7～15 seconds at 710～780 ℃, quench and implement after solution treatment, at 430～470 ℃, maintain three hours, ageing treatment is separated out in enforcement, then carry out cleanup acid treatment, and then be 90～150N/mm at 10～30% working modulus, the tension force that copper alloy plate is given ²and use is finally cold rolling by enforcement under the condition of the roll of the grinding stone grinding of granularity #180～600, and the tension force that copper alloy plate is given in to stove is 300～900N/mm ², the floating distance of copper alloy plate is to implement continuous low temperature annealing under the condition of 10～20mm in stove.

Embodiment

Allotment material, makes it to become the composition shown in table 1, adopts the Low-frequency Flowing Furnace of reducing atmosphere to melt the copper alloy casting ingot that is cast as thickness 80mm, width 200mm, length 800mm size afterwards.This copper alloy casting ingot is heated to after 900～980 ℃, by hot rolling, forms the hot-rolled sheet of thickness 11mm, after this hot-rolled sheet is carried out to water-cooled, by two sides building up by welding 0.5mm.Next, after 87% the rolling rate of take is implemented cold-reduced sheet that cold rolling making thickness is 1.3mm, in 710～750 ℃, maintain under the condition of 7～15 seconds and implement continuous annealing, then carry out pickling and surface grinding, and then take 77% rolling rate and implement cold rolling and make the cold-reduced sheet that thickness is 0.3mm.

This cold-reduced sheet is maintained after 7～15 seconds in 710～780 ℃, quench and implement solution treatment, then at 430～470 ℃, maintain three hours and implement separate out ageing treatment and carry out after cleanup acid treatment, further under condition shown in table 1, implement final cold rolling and continuous low temperature annealing, make copper alloy thin plate.

Next, for each obtained sample, measure arithmetic average roughness Ra, take each peak portion value during as benchmark of surfaceness average line and paddy portion value standard deviation, the aspect ratio of absolute value, the special grain boundary total length L σ of the mean value in all crystal grains of GOS, special grain boundary with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, deep drawing processibility, elastic limit value, solder heat resistance separability, the mean value of fatigue characteristic, the standard deviation of fatigue characteristic.

The arithmetic average roughness Ra on copper alloy plate surface, tries to achieve as follows.

Adopt the contact pin type surface roughness instruments (SE-30D) of the little slope institute system of Co., Ltd., according to JIS B0651-1996, obtain distribution plan, and calculate arithmetic average roughness (Ra) (JIS B0601-1994) based on this distribution plan.

Take the standard deviation of absolute value of each peak portion value during as benchmark of the surfaceness average line on copper alloy plate surface and paddy portion value, try to achieve as follows.

Adopt the contact pin type surface roughness instruments (SE-30D) of the little slope institute system of Co., Ltd., according to JIS B0651-1996, obtain distribution plan, and the absolute value of surfaceness average line each peak portion value and paddy portion value during as benchmark is take in actual measurement based on this distribution plan, and calculate its standard deviation.

The mean value of aspect ratio, tries to achieve as follows.

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of a hour, the sample after watering is implemented to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area (rolling direction) 150 μ m * 150 μ m.

Next, in the step-length with 0.5 μ m, to measuring the orientation of all pixels in area, measure, and be that 5 ° of above boundary definitions are crystal boundary by the misorientation between pixel, the set of two above pixels of being surrounded by crystal boundary is regarded as in the situation of crystal grain, the length of the long axis direction of each crystal grain is made as to a, the length of short-axis direction is made as to b, described b is defined as to aspect ratio divided by the value of described a, obtain the aspect ratio of measuring all crystal grains in area, and calculate its mean value.

Mean value in all crystal grains of GOS, tries to achieve as follows.

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of a hour, the sample after watering is carried out to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area 150 μ m * 150 μ m.

Result, obtains the poor mean value of average orientation between all pixels in crystal grain in all crystal grains under the following conditions according to the observation.

Step-length with 0.5 μ m is measured measuring the orientation of all pixels in areal extent, and is that crystal boundary is regarded on 5 ° of above borders as by the misorientation between neighbor.

Next, for all each crystal grain being surrounded by crystal boundary, through type (1) calculates the mean value (GOS:Grain Orientation Spread) of the misorientation between all pixels in crystal grain respectively, and the average orientation between all pixels in crystal grain in all crystal grains is poor using the mean value of this all values, i.e. mean value in all crystal grains of GOS.In addition, by the crystal grain that is made as of two above pixels connections.

$\mathrm{GOS}=\frac{\underset{i,j=1}{\overset{n}{\mathrm{\&Sigma;}}}{\mathrm{\&alpha;}}_{\mathrm{ij}(i\&NotEqual;j)}}{n(n-1)}...\left(1\right)$

In above formula, i, j represent the pixel number in crystal grain.

N represents the pixel quantity in crystal grain.

α _ijthe misorientation that represents pixel i and j.

The special grain boundary total length L σ of special grain boundary, with respect to the ratio (L σ/L) of the crystal boundary total length L of crystal boundary, tries to achieve as follows.

As pre-treatment, the sample of 10mm * 10mm is flooded in 10% sulfuric acid and within 10 minutes, wash afterwards, and after sprinkling water with air blast, adopt slabbing (ion beam milling) device of high and new technology company of Hitachi system under acceleration voltage 5kV, 5 ° of input angles, the irradiation time condition of a hour, the sample after watering is carried out to surface treatment.

Next, adopt the scanning electronic microscope S-3400N processed of high and new technology company of Hitachi of DaiTSL company EBSD system processed to observe this specimen surface.Observation condition is acceleration voltage 25kV, mensuration area 150 μ m * 150 μ m.

Step-length with 0.5 μ m is measured measuring the orientation of all pixels in areal extent, and is that crystal boundary is regarded on 5 ° of above borders as by the misorientation between neighbor.

Next, crystal boundary total length L to the crystal boundary in measurement range is measured, and determine that the interface of adjacent crystal grain forms the position of the crystal boundary of special grain boundary, and obtain the crystal boundary length ratio L σ/L of the crystal boundary total length L of the special grain boundary total length L σ of special grain boundary and the crystal boundary of said determination, using it as special grain boundary length ratio.

Deep drawing processibility is tried to achieve as follows.

Adopt the test machine of Sven-Gan Eriksson company (エ リクセン society) system, in punching hole diameter: Φ 10mm, lubricant: under the condition of lubricating oil, make cup, observe outward appearance, good is made as to zero, lip portions produce being made as of damaged or crackle *.

Elastic limit value is tried to achieve as follows.

According to JIS-H3130, by torque type test determination permanent deflection amount, and calculate Kb0.1(in R.T. corresponding to the surperficial maximum stress value on the inboardend of permanent deflection amount 0.1mm).

Solder heat resistance separability is tried to achieve as follows.

Each obtained sample is cut into the rectangle of width 10mm, length 50mm, and it is flooded to five seconds in the 60%Sn-40%Pb scolder of 230 ℃ ± 5 ℃.Flux is used 25% rosin-ethanol.This material is heated 1000 hours in 150 ℃, and with the radius-of-curvature 90-degree bent identical with thickness of slab, and by after its reinstatement, detect by an unaided eye and have solderless peeling off at bend.

The mean value of fatigue characteristic and the standard deviation of fatigue characteristic are tried to achieve as follows.

Fatigue test is according to JIS Z2273, and the rectangle testing plate that is 10mm to the width in the direction parallel with rolling direction is carried out.The maximum additional stress (stress on inboardend) of measuring testing plate surface is the fatigue lifetime of 400MPa part (until repetitive vibrations number of times of testing plate fracture).Carry out under the same conditions four times and measure, and calculate the standard deviation of four measured values.

In these measurement results shown in table 2.

As known from Table 2, Cu-Ni-Si series copper alloy of the present invention can maintain the balance between deep drawing processibility, solder heat resistance separability and elastic limit value, the change of resistent fatigue characteristic is few, especially there is excellent deep drawing processibility, use in being suitable for being exposed to for a long time the electronic unit under harsh environment for use under high temperature and high vibration.

The manufacture method of embodiments of the present invention has more than been described, but the present invention is not limited to above-mentioned record, can carries out various changes without departing from the spirit and scope of the present invention.

Applicability in industry

Cu-Ni-Si series copper alloy plate of the present invention is used in being suitable for being exposed to for a long time the electronic unit under harsh environment for use under high temperature and high vibration.

Nomenclature

11 Abrollhaspel 12 tenslators

13 Horizental annealer 14 tenslators

15 grindings, pickler 16 pulling reels

F copper alloy plate G hot blast

Claims (6)

1. a Cu-Ni-Si series copper alloy plate, the Ni that contains 1.0～3.0 quality %, and contain concentration and be 1/6～1/4 Si of the quality % concentration of Ni, surplus is Cu and inevitable impurity, the arithmetic average roughness Ra on surface is 0.02～0.2 μ m, take the standard deviation of surfaceness average line absolute value of each peak portion value and paddy portion value during as benchmark below 0.1 μ m, the aspect ratio of crystal grain in alloy structure, the mean value that is crystal grain minor axis/crystal grain major diameter is 0.4～0.6, when measuring measuring the orientation of all pixels in areal extent according to the EBSD method of the scanning electronic microscope of use having electronic back scattering diffraction picture system, and be that 5 ° of above borders are considered as in the situation of crystal boundary by the misorientation between neighbor, mean value in all crystal grains of GOS is 1.2～1.5 °, the special grain boundary total length L σ of special grain boundary is with respect to the ratio of the crystal boundary total length L of crystal boundary, be that L σ/L is 60～70%, elastic limit value is 450～600N/mm ², the solder heat resistance separability under 150 ℃ and 1000 hours is good, and the change of resistent fatigue characteristic is few, has excellent deep drawing processibility.

2. Cu-Ni-Si series copper alloy plate according to claim 1, is characterized in that, further contains the Sn of 0.2～0.8 quality % and the Zn of 0.3～1.5 quality %.

3. Cu-Ni-Si series copper alloy plate according to claim 1, is characterized in that, further contains the Mg of 0.001～0.2 quality %.

4. Cu-Ni-Si series copper alloy plate according to claim 2, is characterized in that, further contains the Mg of 0.001～0.2 quality %.

5. according to the Cu-Ni-Si series copper alloy plate described in any one in claim 1～4, it is characterized in that, further contain one or more in Fe:0.007～0.25 quality %, P:0.001～0.2 quality %, C:0.0001～0.001 quality %, Cr:0.001～0.3 quality %, Zr:0.001～0.3 quality %.

6. a manufacture method for Cu-Ni-Si series copper alloy plate, is characterized in that, is the method for the Cu-Ni-Si series copper alloy plate described in manufacture claim 1,

When comprising successively hot rolling, cold rolling, solution treatment, ageing treatment, final cold rolling and stress relief annealed technique manufactured copper alloy sheets, the working modulus 10～30%, the tension force that copper alloy plate is given are 90～150N/mm ², and use and under the condition of the roll that the grinding stone be #180～600 by granularity grinds, to implement finally cold rollingly, and the tension force that copper alloy plate is given in to stove is 300～900N/mm ², the floating distance of copper alloy plate is to implement continuous low temperature annealing under the condition of 10～20mm in stove.

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