Phosphorus bronze alloy strip and preparation method thereof

Abstract

The invention provides a phosphor bronze alloy strip and a preparation method thereof, and relates to the technical field of copper alloys. The phosphor bronze alloy strip provided by the invention comprises the following components in percentage by mass: 11%-11.5% of Sn, 0.05%-0.35% of P, 0.01%-0.2% of Zn, 0.01%-0.15% of Fe, 0.01%-0.1% of Ni, 0.01%-0.4% of Ag, 0.01%-0.4% of In and / or Bi and the balance of Cu. The average grain size of the phosphor bronze alloy strip is 0.1-10 [mu] m, the tensile strength is 650-850 MPa, the ductility is 45-60%, the surface roughness is 0.06-0.15 [mu] m, and the 90-degree bending property is that the phosphor bronze alloy strip does not crack in the GW and BW directions under the conditions that R / T is equal to 0 and R / T is equal to 0.5, and the phosphor bronze alloy strip can meet key basic materials in the fields of aerospace sensors, automobile braking systems and the like.

Description

Technical Field

[0001] The invention relates to the technical field of copper alloys, and in particular to a phosphor bronze alloy strip and a preparation method thereof. Background Art

[0002] In the brazing field of aircraft engine combustion chamber baffles and marine engineering connectors that bear high-strength static loads, Ni and Cu-based brazing fillers are used preferentially to obtain high-performance welded joints. However, Ni-based brazing fillers have high brazing temperatures (≥1100°C), large amounts of parent metal dissolution, and poor joint processing performance. Therefore, when there is no need to bear large dynamic loads, Cu-based brazing fillers have the advantages of low melting point, easy processing, and corrosion resistance. In addition, high-performance Cu-based alloys are widely used in aerospace sensors, automotive braking systems, and complex structure medical devices as parent materials for connection with high-strength metals such as stainless steel and titanium alloys.

[0003] The heterogeneous metals connected by high-performance Cu-based solder and parent materials are usually stainless steel, high-temperature alloys or titanium alloys. In order to ensure the quality of welding, an appropriate amount of Pb is added to the Cu-based material, which can not only reduce the melting point and surface tension of the solder, but also improve the impact resistance of the welding joint. However, the waste, lead-containing vapor or dust generated during the production and use of Pb-containing copper-based materials will cause long-term damage to the surrounding ecological environment and personnel. The development of environmentally friendly low-melting-point (≤960℃) and high-strength Cu-based materials such as lead-free and cadmium-free has become a trend.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The first object of the present invention is to provide a phosphor bronze alloy strip to solve the above technical problems.

[0006] A second object of the present invention is to provide a method for preparing the phosphor bronze alloy strip.

[0007] In order to achieve the above objectives, the following technical solutions are adopted:

[0008] In a first aspect, the present invention provides a phosphor bronze alloy strip, comprising, by mass percentage, Sn 11% to 11.5%, P 0.05% to 0.35%, Zn 0.01% to 0.2%, Fe 0.01% to 0.15%, Ni 0.01%-0.1%, Ag0.01%-0.4%, In and / or Bi 0.01% to 0.4%, and the balance is Cu.

[0009] In a second aspect, the present invention provides a method for preparing the above-mentioned phosphor bronze alloy strip, comprising the following steps:

[0010] The materials are prepared according to the mass percentage, and then smelting, casting, first homogenization annealing, milling, first cold rolling, second homogenization annealing, second cold rolling, first recrystallization annealing, third cold rolling, second recrystallization annealing, fourth cold rolling, third recrystallization annealing, fifth cold rolling and stress annealing are carried out in sequence to prepare a phosphor bronze alloy strip.

[0011] As a further technical solution, the smelting temperature is 1200-1280°C;

[0012] The casting is horizontal continuous casting, the casting temperature is 1165-1250°C, and the casting speed is 120-140 mm / min;

[0013] The first homogenization annealing is carried out in a bell furnace, the annealing temperature is 650-730° C., the holding time is 8.5-10 hours, and the annealing atmosphere is a protective atmosphere.

[0014] As a further technical solution, the deformation processing rate of the first cold rolling is 60% to 70%;

[0015] The second homogenization annealing is carried out in a bell furnace, the annealing temperature is 600-700° C., the insulation time is 7-9 hours, and the annealing atmosphere is a protective atmosphere.

[0016] As a further technical solution, the deformation processing rate of the second cold rolling is 65% to 80%;

[0017] The first recrystallization annealing is carried out in a bell furnace, the annealing temperature is 400-550° C., the holding time is 5-8 hours, and the annealing atmosphere is a protective atmosphere.

[0018] As a further technical solution, a step of cutting off the alloy edge is included between the second cold rolling and the first recrystallization annealing.

[0019] As a further technical solution, the deformation processing rate of the third cold rolling is 60% to 75%;

[0020] The second recrystallization annealing is carried out in a bell furnace, the annealing temperature is 350-500° C., the holding time is 4-6 hours, and the annealing atmosphere is a protective atmosphere.

[0021] As a further technical solution, brushing and pickling are also included between the second recrystallization annealing and the fourth cold rolling to remove impurities and oxide layers on the alloy surface.

[0022] As a further technical solution, the deformation processing rate of the fourth cold rolling is 40% to 50%;

[0023] The third recrystallization annealing is carried out in a vertical annealing furnace at a temperature of 450-550° C. and an annealing speed of 12-20 m / min. Cooling is carried out in a protective atmosphere at a cooling speed of 60-75° C. / s.

[0024] As a further technical solution, the deformation processing rate of the fifth cold rolling is 40% to 50%;

[0025] The stress annealing temperature is 250-300° C., and the annealing speed is 8-10 m / min.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The phosphor bronze alloy strip provided by the present invention adds Zn element on the basis of copper-tin-phosphorus alloy, which can improve the fluidity of the alloy, reduce reverse segregation, and significantly improve the wettability of the solder on the metal surface; adding Fe element can refine the grains, delay the copper recrystallization process, and improve the strength and hardness of the alloy; adding Ni element can improve the strength and toughness of the alloy, improve the wettability and corrosion resistance of the solder on the metal surface; adding Ag, In or Bi can reduce the melting point of the solder and improve the welding performance. The phosphor bronze alloy strip has an average grain size of 0.1-10 μm, a tensile strength of 650-850 MPa, an elongation of 45-60%, a surface roughness of 0.06-0.15 μm, and a 90° bending performance: no cracking in the GW and BW directions under the conditions of R / T=0 and R / T=0.5, which can meet the key basic materials in the fields of aerospace sensors, automotive braking systems, and complex structure medical devices. DETAILED DESCRIPTION

[0028] The embodiments of the present invention will be described in detail below in conjunction with the embodiments and examples, but it will be appreciated by those skilled in the art that the following embodiments and examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. If specific conditions are not specified, proceed according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0029] In the first aspect, the present invention provides a phosphor bronze alloy strip, mainly composed of Sn, P, Zn, Fe, Ni, Ag, Cu, and In or Bi. The content of Sn may be, for example, but not limited to 11%, 11.3% or 11.5%; the content of P may be, for example, but not limited to 0.05%, 0.25% or 0.35%; the content of Zn may be, for example, but not limited to 0.01%, 0.1% or 0.2%; the content of Fe may be, for example, but not limited to 0.01%, 0.1% or 0.15%; the content of Ni may be, for example, but not limited to 0.01%, 0.05% or 0.1%; the content of Ag may be, for example, but not limited to 0.01%, 0.2% or 0.4%; the content of In and / or Bi may be, for example, but not limited to 0.01%, 0.3% or 0.4%.

[0030] It should be noted that, in the present invention, “In and / or Bi” means that it may be In, it may be Bi, or it may be In and Bi.

[0031] In the present invention, Sn can reduce the melting point of the alloy and improve the wear resistance and corrosion resistance of the solder. However, the disadvantage is that the solidification range of the Cu-Sn alloy is large and reverse segregation of tin is prone to occur.

[0032] P is easily oxidized and is an effective deoxidizer for copper alloys. It can improve the process performance of copper alloys and reduce the melting point of alloys. The disadvantage is that the brittle compound Cu3P produced by it and copper is easy to form a eutectic with the α phase, expanding the crystallization temperature range and causing segregation.

[0033] Zn has a high solubility in α solid solution, which improves alloy fluidity, narrows the crystallization temperature range, reduces reverse segregation, and significantly improves the wettability of the brazing material on the metal surface. However, the inventors have found that when the mass fraction is greater than 0.2%, it is easy to cause brittle cracking due to stress corrosion.

[0034] Fe has extremely low solubility in solid copper and is distributed in the α matrix in the form of iron-rich phase particles, which can refine grains, delay the copper recrystallization process, and improve the strength and hardness of the alloy. However, the inventors have found that when the mass fraction is greater than 0.2%, the iron-rich phase tends to aggregate at the grain boundaries, leading to hot cracking.

[0035] A small amount of Ni addition can increase the strength and toughness of the alloy, and improve the wettability and corrosion resistance of the brazing filler metal surface.

[0036] Ag can improve the weldability of copper alloys, lower the melting point and increase wettability, making welding easier, while also helping to increase the tensile strength of welded joints;

[0037] In can significantly reduce the melting point and help improve wettability, which is beneficial to improving welding performance. In addition, indium can also enhance the conductivity and corrosion resistance of the alloy, but excessive addition may cause phase separation or coarse grains, making the alloy brittle;

[0038] Bi can also effectively reduce the melting point and form a low melting point eutectic phase with the α solid solution, thereby improving weldability. At the same time, Bi also has good fluidity and wettability, which is beneficial to weld formation. However, excessive addition is prone to form hot cracks, leading to cracking of the alloy.

[0039] In particular, although adding In or Bi can play a beneficial role to a certain extent (such as reducing the melting point and improving welding performance), there is a gap compared with the effect of adding Ag element. Adding In or Bi in appropriate amounts can reduce the dependence on Ag and thus reduce costs. However, excessive addition may cause cracking of the alloy. In order to ensure that the alloy maintains a low melting point and good welding performance, in the present invention, the amount of Ag added should not be less than 0.01%.

[0040] In some optional embodiments, the phosphor bronze alloy strip has a thickness of 0.06-0.3 mm and a width of ≥600 mm.

[0041] In a second aspect, the present invention provides a method for preparing the above-mentioned phosphor bronze alloy strip, comprising the following steps:

[0042] The materials are prepared according to the mass percentage, and then smelting, casting, first homogenization annealing, milling, first cold rolling, second homogenization annealing, second cold rolling, first recrystallization annealing, third cold rolling, second recrystallization annealing, fourth cold rolling, third recrystallization annealing, fifth cold rolling and stress annealing are carried out in sequence to prepare a phosphor bronze alloy strip.

[0043] Phosphor bronze alloy has high hardness and is prone to dimensional accuracy and plate shape problems during rolling. Therefore, a full-process low-temperature multiple cold processing process is adopted to obtain alloy strips with fine and uniform structure, no component segregation, high dimensional accuracy and good plate shape. At the same time, by regulating the alloy structure, the alloy strength and elongation can be synergistically improved, and the alloy bending performance can be improved; combined with the reasonable allocation of heat treatment and rolling parameters, integrated control of alloy size and surface quality can be achieved.

[0044] In some optional embodiments, the smelting temperature may be, for example, but not limited to, 1200° C., 1240° C. or 1280° C.;

[0045] The casting is horizontal continuous casting, the casting temperature may be, for example, but not limited to, 1165° C., 1200° C. or 1250° C., and the casting speed may be, for example, but not limited to, 120 mm / min, 130 mm / min or 140 mm / min;

[0046] The first homogenization annealing is performed in a bell furnace, the annealing temperature may be, but not limited to, 650° C., 700° C. or 730° C., the holding time may be, but not limited to, 8.5 h, 9 h or 10 h, and the annealing atmosphere is a protective atmosphere.

[0047] The first homogenization annealing can eliminate casting stress and component segregation of the strip obtained by horizontal continuous casting and prevent cracking during rough rolling.

[0048] In some optional embodiments, the specifications of the Su Sohu ingot are: width ≥ 630 mm, thickness ≥ 190 mm.

[0049] In some optional embodiments, the strip blank after the first homogenization annealing is milled, and for example, 0.5 mm can be milled off each side of the strip blank. The specific operation technique is not limited, and methods familiar to those skilled in the art can be used.

[0050] In some optional embodiments, the deformation processing rate of the first cold rolling may be, for example, but not limited to, 60%, 65% or 70%, and a multi-pass small deformation process is adopted, with the rolling ratio of each pass controlled at 10-15%, to finally obtain the target thickness;

[0051] The second homogenization annealing is performed in a bell furnace, the annealing temperature may be, but not limited to, 600° C., 650° C. or 700° C., the holding time may be, but not limited to, 7 h, 8 h or 9 h, and the annealing atmosphere is a protective atmosphere.

[0052] The second homogenization annealing is performed to homogenize the alloy composition and reduce the hardness of the plate.

[0053] In some optional embodiments, the deformation processing rate of the second cold rolling may be, for example, but not limited to, 65%, 70% or 80%, and a multi-pass small deformation process is adopted, and the rolling ratio of each pass is controlled at 10-15%, and finally the target thickness is obtained;

[0054] The first recrystallization annealing is performed in a bell furnace, the annealing temperature may be, but not limited to, 400°C, 500°C or 550°C, the holding time may be, but not limited to, 5h, 6h or 8h, and the annealing atmosphere is a protective atmosphere.

[0055] The first recrystallization annealing is performed to refine the crystals, reduce the hardness of the plate and control the plate shape.

[0056] In some optional embodiments, the step of cutting off the edge of the alloy is further included between the second cold rolling and the first recrystallization annealing to prevent edge defects from affecting the surface quality of the plate, and the cutting thickness can be 5 to 10 mm.

[0057] In some optional embodiments, the deformation processing rate of the third cold rolling can be, for example, but not limited to, 60%, 70% or 75%, and a multi-pass small deformation process is adopted, and the rolling ratio of each pass is controlled at 10-15%, and finally the target thickness is obtained;

[0058] The second recrystallization annealing is performed in a bell furnace. The annealing temperature may be, but is not limited to, 350° C., 400° C. or 500° C., the holding time may be, but is not limited to, 4 h, 5 h or 6 h, and the annealing atmosphere is a protective atmosphere.

[0059] In some optional embodiments, brushing and pickling are also included between the second recrystallization annealing and the fourth cold rolling to remove impurities and oxide layer on the surface of the alloy to avoid affecting the subsequent finishing rolling, thereby obtaining a plate and strip with high surface quality and good plate shape.

[0060] In the present invention, the brushing and pickling parameters include: grinding current of 18-27A, grinding brush speed of 800-950 rpm, and pickling rate of 25-38 m / min.

[0061] In some optional embodiments, the deformation processing rate of the fourth cold rolling can be, for example, but not limited to, 40%, 45% or 50%, and a multi-pass small deformation process is adopted, and the rolling ratio of each pass is controlled at 10-15%, and finally the target thickness is obtained;

[0062] The third recrystallization annealing is carried out in a vertical annealing furnace. The annealing temperature may be, for example, but not limited to 450°C, 500°C or 550°C. The annealing speed may be, for example, but not limited to 12m / min, 16m / min or 20m / min. Cooling is carried out in a protective atmosphere. The cooling speed may be, for example, but not limited to 60°C / s, 70°C / s or 75°C / s.

[0063] In some optional embodiments, the deformation processing rate of the fifth cold rolling can be, for example, but not limited to, 40%, 45% or 50%, and a multi-pass small deformation process is adopted, and the rolling ratio of each pass is controlled at 10-15%, and finally the target thickness is obtained;

[0064] In particular, through the above-mentioned multiple low-temperature recrystallization annealing + multiple small deformation rolling treatments, the alloy can obtain a microstructure with fine and uniform grains, inhibit component segregation, and synergistically improve the mechanical, electrical and bending forming properties of the alloy, while obtaining higher dimensional accuracy, plate shape and surface quality.

[0065] The stress annealing temperature may be, for example, but not limited to, 250° C., 280° C. or 300° C., and the annealing speed may be, for example, but not limited to, 8 m / min, 9 m / min or 10 m / min.

[0066] In particular, stress relief annealing can reduce the residual stress of the strip, which is conducive to obtaining a better plate shape.

[0067] In some optional embodiments, the stress annealing further includes stretch bending straightening, with an unwinding tension of 18-20N, a winding tension of 35-70N, and an inlet extension of 0.01-0.2%.

[0068] The present invention is further described below by means of specific examples and comparative examples. However, it should be understood that these examples are only used for more detailed description and should not be construed as limiting the present invention in any form.

[0069] It should be noted that in the following embodiments and comparative examples, pre-rough rolling refers to the first cold rolling, rough rolling refers to the second cold rolling, intermediate rolling refers to the third cold rolling, pre-finishing rolling refers to the fourth cold rolling, and finishing rolling refers to the fifth cold rolling.

[0070] Embodiment 1:

[0071] The alloy compositions are shown in Table 1.

[0072] Electrolytic copper, tin ingot, electrolytic nickel, iron wire (1 mm in diameter), 15% Cu-P master alloy, zinc ingot, 10% Cu-Ag master alloy, 5% Cu-In master alloy and 5% Cu-Bi master alloy are added to the alloy raw materials in order according to the mass ratio of the components. After the metals are completely melted, they are stirred to make the metal melts evenly mixed.

[0073] Melting and casting: weigh the raw materials according to the alloy composition ratio, mix them, and then perform melting and horizontal continuous casting in sequence. The melting temperature is 1270℃, the casting temperature is 1200℃, the normal casting speed is 130mm / min, and the strip is processed;

[0074] First homogenization annealing: The strip obtained by horizontal continuous casting is placed in a bell furnace for homogenization annealing at a temperature of 700°C for 9 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0075] Milling: mill the strip after the first homogenization annealing, milling 0.5mm on both sides of the strip. The specific operation method is not limited, and the method familiar to those skilled in the art can be used;

[0076] Pre-rough rolling: cold rolling the alloy strip after milling, with a deformation rate of 65%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 12%, to finally obtain the target thickness;

[0077] The second homogenization annealing is to place the plate obtained by pre-rough rolling in a bell furnace for homogenization annealing at a temperature of 650°C for 8 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0078] Rough rolling: cold rolling the plate obtained by the second homogenization annealing, with a deformation processing rate of 72%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 12%, to finally obtain the target thickness;

[0079] Rough cutting: the plate obtained by rough rolling is roughly cut, and 8mm is cut off on one side;

[0080] For the first recrystallization annealing, the rough-cut plate is placed in a bell furnace for recrystallization annealing at a temperature of 500°C for 7 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0081] Medium rolling: cold rolling the alloy sheet after the first recrystallization annealing, with a deformation processing rate of 73%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 12%, to finally obtain the target thickness;

[0082] Second recrystallization annealing: the strip obtained by intermediate rolling is placed in a bell furnace for second recrystallization annealing at a temperature of 450°C for 5 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0083] Brush pickling, grinding current is 20A, grinding brush speed is 900 rpm, pickling rate is 30m / min;

[0084] Pre-finish rolling: cold rolling the strip after brush pickling, with a deformation rate of 50%, using a multi-pass small deformation process, and the rolling ratio of each pass is controlled at 12%, and finally the target thickness is obtained;

[0085] The third recrystallization annealing is to put the strip obtained by pre-finishing rolling into a vertical annealing furnace for continuous annealing at a temperature of 500°C and a continuous annealing speed of 18 m / min. The strip is cooled by a mixed gas of hydrogen and nitrogen at a cooling speed of 70°C / s.

[0086] Finish rolling: cold rolling the strip after the third recrystallization annealing, with a deformation processing rate of 50%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 12%, to finally obtain the target thickness;

[0087] Stress relief annealing: the strip obtained by finish rolling is subjected to stress relief annealing, the annealing temperature is 280°C, and the annealing speed is 9m / min;

[0088] Stretch bending straightening, unwinding tension 19N, winding tension 60N, inlet extension 0.1%.

[0089] Embodiment 2:

[0090] The alloy compositions are shown in Table 1.

[0091] Electrolytic copper, tin ingot, electrolytic nickel, iron wire (1 mm in diameter), 15% Cu-P master alloy, zinc ingot, 10% Cu-Ag master alloy, 5% Cu-In master alloy are added to the alloy raw materials in order according to the mass ratio of the components. After the metals are completely melted, they are stirred to make the metal melts evenly mixed.

[0092] Melting and casting: weigh the raw materials according to the alloy composition ratio, mix them, and then perform melting and horizontal continuous casting in sequence. The melting temperature is 1200℃, the casting temperature is 1165℃, the normal casting speed is 120mm / min, and the strip is processed;

[0093] First homogenization annealing: The strip obtained by horizontal continuous casting is placed in a bell furnace for homogenization annealing at a temperature of 650°C for 10 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0094] Milling: mill the strip after the first homogenization annealing, milling 0.5mm on both sides of the strip. The specific operation method is not limited, and the method familiar to those skilled in the art can be used;

[0095] Pre-rough rolling: cold rolling the alloy strip after milling, with a deformation rate of 70%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 15%, to finally obtain the target thickness;

[0096] The second homogenization annealing is to place the plate obtained by pre-rough rolling in a bell furnace for homogenization annealing at a temperature of 600°C for 9 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0097] Rough rolling: cold rolling the plate obtained by the second homogenization annealing, with a deformation processing rate of 80%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 15%, and finally obtaining the target thickness;

[0098] Rough cutting: the plate obtained by rough rolling is roughly cut, and 5mm is cut on one side;

[0099] The first recrystallization annealing, the rough cut plate is placed in a bell furnace for recrystallization annealing, the annealing temperature is 400 ° C, the temperature is kept for 8 hours, and the protective atmosphere is a mixture of hydrogen and nitrogen;

[0100] Medium rolling: cold rolling the alloy plate after the first recrystallization annealing, with a deformation processing rate of 75%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 15%, and finally obtaining the target thickness;

[0101] Second recrystallization annealing: the strip obtained by intermediate rolling is placed in a bell furnace for second recrystallization annealing at a temperature of 350°C for 6 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0102] Brush pickling, grinding current is 18A, grinding brush speed is 800 rpm, pickling rate is 25m / min;

[0103] Pre-finish rolling: cold rolling the strip after brush pickling, with a deformation rate of 48%, using a multi-pass small deformation process, and each pass rolling ratio controlled at 15%, and finally obtaining the target thickness;

[0104] The third recrystallization annealing is to put the strip obtained by pre-finishing rolling into a vertical annealing furnace for continuous annealing at a temperature of 450°C and a continuous annealing speed of 12 m / min. The strip is cooled by a mixed gas of hydrogen and nitrogen at a cooling speed of 60°C / s.

[0105] Finish rolling: cold rolling the strip after the third recrystallization annealing, with a deformation processing rate of 48%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 15%, to finally obtain the target thickness;

[0106] Stress relief annealing: the strip obtained by finish rolling is subjected to stress relief annealing at a temperature of 250°C and an annealing speed of 8 m / min;

[0107] Stretch bending straightening, unwinding tension 18N, winding tension 35N, inlet extension 0.01%.

[0108] Embodiment 3:

[0109] The alloy compositions are shown in Table 1.

[0110] Electrolytic copper, tin ingot, electrolytic nickel, iron wire (1 mm in diameter), 15% Cu-P master alloy, zinc ingot, 10% Cu-Ag master alloy, 5% Cu-In master alloy and 5% Cu-Bi master alloy are added to the alloy raw materials in order according to the mass ratio of the components. After the metals are completely melted, they are stirred to make the metal melts evenly mixed.

[0111] Melting and casting: weigh the raw materials according to the alloy composition ratio, mix them, and then perform melting and horizontal continuous casting in sequence. The melting temperature is 1280℃, the casting temperature is 1250℃, the normal casting speed is 140mm / min, and the strip is processed;

[0112] First homogenization annealing: The strip obtained by horizontal continuous casting is placed in a bell furnace for homogenization annealing at a temperature of 730°C for 8.5 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0113] Milling: mill the strip after the first homogenization annealing, milling 0.5mm on both sides of the strip. The specific operation method is not limited, and the method familiar to those skilled in the art can be used;

[0114] Pre-rough rolling: cold rolling the alloy strip after milling, with a deformation rate of 60%, using a multi-pass small deformation process, with the rolling ratio of each pass controlled at 10%, and finally obtaining the target thickness;

[0115] The second homogenization annealing is to place the plate obtained by pre-rough rolling in a bell furnace for homogenization annealing at a temperature of 700°C for 7 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0116] Rough rolling: cold rolling the plate obtained by the second homogenization annealing, with a deformation processing rate of 65%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 10%, and finally obtaining the target thickness;

[0117] Rough cutting: the plate obtained by rough rolling is roughly cut, and 10mm is cut off on one side;

[0118] The first recrystallization annealing, the rough cut plate is placed in a bell furnace for recrystallization annealing, the annealing temperature is 550 ° C, the temperature is kept for 5 hours, and the protective atmosphere is a mixture of hydrogen and nitrogen;

[0119] Medium rolling: cold rolling the alloy sheet after the first recrystallization annealing, with a deformation processing rate of 60%, using a multi-pass small deformation process, with the rolling ratio of each pass controlled at 10%, and finally obtaining the target thickness;

[0120] Second recrystallization annealing: the strip obtained by intermediate rolling is placed in a bell furnace for secondary recrystallization annealing at a temperature of 500°C for 4 hours in a protective atmosphere of a mixture of hydrogen and nitrogen.

[0121] Brush pickling, grinding current is 27A, grinding brush speed is 950 rpm, pickling rate is 38m / min;

[0122] Pre-finish rolling: cold rolling the strip after brush pickling, with a deformation rate of 40%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 10%, to finally obtain the target thickness;

[0123] The third recrystallization annealing is to put the strip obtained by pre-finishing rolling into a vertical annealing furnace for continuous annealing at a temperature of 550°C and a continuous annealing speed of 20 m / min. The strip is cooled by a mixture of hydrogen and nitrogen at a cooling speed of 75°C / s.

[0124] Finish rolling: cold rolling the strip after the third recrystallization annealing, with a deformation processing rate of 40%, using a multi-pass small deformation process, and controlling the rolling ratio of each pass at 10%, to finally obtain the target thickness;

[0125] Stress relief annealing: the strip obtained by finish rolling is subjected to stress relief annealing at a temperature of 300°C and an annealing speed of 10 m / min;

[0126] Stretch straightening, unwinding tension 20N, winding tension 70N, inlet extension 0.2%.

[0127] Embodiment 4:

[0128] The difference from Example 1 is that Bi element is not added, but a small amount of Ag element and In element are added, with the added amount being Ag 0.01% and In 0.01%.

[0129] Embodiment 5:

[0130] The difference from Example 1 is that no In element is added, but a small amount of Ag and Bi elements are added, with the added amounts being 0.01% Ag and 0.01% Bi.

[0131] Comparative Example 1:

[0132] The difference from Example 1 is that the Sn element is added below the range, and the added amount is 9%.

[0133] Comparative Example 2:

[0134] The difference from Example 1 is that no P element is added.

[0135] Comparative Example 3:

[0136] The difference from Example 1 is that an excessive amount of Zn element is added, and the added amount is 0.4%.

[0137] Comparative Example 4:

[0138] The difference from Example 1 is that no Zn element is added.

[0139] Comparative Example 5:

[0140] The difference from Example 1 is that an excessive amount of Fe element is added, and the added amount is 0.4%.

[0141] Comparative Example 6:

[0142] The difference from Example 1 is that no Ni element is added.

[0143] Comparative Example 7:

[0144] The difference from Example 2 is that Ag and In elements are not added.

[0145] Comparative Example 8:

[0146] The difference from Example 1 is that an excessive amount of In element is added, and the added amount is 0.5%.

[0147] Comparative Example 9:

[0148] The difference from Example 1 is that an excessive amount of Bi element is added, and the added amount is 0.5%.

[0149] Comparative Example 10:

[0150] The difference from Example 1 is that no Ag element is added.

[0151] Comparative Example 11:

[0152] The difference from the embodiment is that there is no first homogenization annealing and pre-rough rolling, and the strip obtained from the horizontal continuous casting is directly cold rolled after milling, with a deformation amount of 90.2%.

[0153] Comparative Example 12:

[0154] The difference from Example 1 is that the primary recrystallization annealing temperature is 600° C. (>550° C.).

[0155] Comparative Example 13:

[0156] The difference from Example 1 is that there is no pre-finishing rolling and the third recrystallization annealing, the strip is deformed by 73% through intermediate rolling and then subjected to secondary recrystallization annealing, and then directly to finishing rolling with a deformation of 74%.

[0157] Table 1 Alloy composition formula of the embodiment and comparative example

[0158]

[0159]

[0160] The alloys of the above embodiments and comparative examples were tested, and the results are shown in Table 2.

[0161] Table 2 Alloy properties and organizational structure of the embodiments and comparative examples

[0162]

[0163]

[0164] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A phosphor bronze alloy strip, characterized in that: Calculated by mass percentage, it includes: Sn 11% to 11.5%, P 0.05% to 0.35%, Zn 0.01% to 0.2%, Fe 0.01% to 0.15%, Ni 0.01%-0.1%, Ag 0.01%-0.4%, In and / or Bi 0.01% to 0.4%, and the balance is Cu.

2. The method for preparing the phosphor bronze alloy strip according to claim 1, characterized in that: The following steps are involved: The materials are prepared according to the mass percentage, and then smelting, casting, first homogenization annealing, milling, first cold rolling, second homogenization annealing, second cold rolling, first recrystallization annealing, third cold rolling, second recrystallization annealing, fourth cold rolling, third recrystallization annealing, fifth cold rolling and stress annealing are carried out in sequence to prepare a phosphor bronze alloy strip.

3. The preparation method according to claim 2, characterized in that: The smelting temperature is 1200-1280°C; The casting is horizontal continuous casting, the casting temperature is 1165-1250°C, and the casting speed is 120-140 mm / min; The first homogenization annealing is carried out in a bell furnace, the annealing temperature is 650-730° C., the holding time is 8.5-10 hours, and the annealing atmosphere is a protective atmosphere.

4. The preparation method according to claim 2, characterized in that: The deformation processing rate of the first cold rolling is 60% to 70%; The second homogenization annealing is carried out in a bell furnace, the annealing temperature is 600-700° C., the insulation time is 7-9 hours, and the annealing atmosphere is a protective atmosphere.

5. The preparation method according to claim 2, characterized in that: The deformation processing rate of the second cold rolling is 65% to 80%; The first recrystallization annealing is carried out in a bell furnace, the annealing temperature is 400-550° C., the holding time is 5-8 hours, and the annealing atmosphere is a protective atmosphere.

6. The preparation method according to claim 2, characterized in that: The step of cutting off the alloy edge is also included between the second cold rolling and the first recrystallization annealing.

7. The preparation method according to claim 2, characterized in that: The deformation processing rate of the third cold rolling is 60% to 75%; The second recrystallization annealing is carried out in a bell furnace, the annealing temperature is 350-500° C., the holding time is 4-6 hours, and the annealing atmosphere is a protective atmosphere.

8. The preparation method according to claim 2, characterized in that: Brushing and pickling are also performed between the second recrystallization annealing and the fourth cold rolling to remove impurities and oxide layers on the alloy surface.

9. The preparation method according to claim 2, characterized in that: The deformation processing rate of the fourth cold rolling is 40% to 50%; The third recrystallization annealing is carried out in a vertical annealing furnace at a temperature of 450-550° C. and an annealing speed of 12-20 m / min. Cooling is carried out in a protective atmosphere at a cooling speed of 60-75° C. / s.

10. The preparation method according to claim 2, characterized in that: The deformation processing rate of the fifth cold rolling is 40% to 50%; The stress annealing temperature is 250-300° C., and the annealing speed is 8-10 m / min.

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