WO2016150194A1 - Wide ultra-thin pure silver foil strip and method for manufacturing same - Google Patents

Abstract

A wide ultra-thin pure silver foil strip and a method for manufacturing same. The manufacturing method comprises: (1) smelting, (2) making pure silver liquid to be a melt, pulling the melt at the temperature of 700-960℃ to form a silver plate with the width of 200-600mm and the thickness of 8-10mm, and rolling during the pulling process; (3) rough rolling; (4) intermediate rolling; (5) finish rolling, (6) annealing; (7) foil rolling; (8) after treatment. In the manufacturing method, the pulling step is adopted so that the fracture phenomenon of the processing material due to stamping force in cold-rolling process can be avoided, and it is ensured that longer silver plate can be obtained by the processing. In the whole rolling procedure, only rough rolling, intermediate rolling, finish rolling and foil rolling are needed, and the rolling procedure is simplified. Before foil rolling, only one annealing is needed, so that many times of oxygen-free vacuum annealing is avoided and the obtained pure silver foil strip is wide and ultra-thin.

Description

Wide-width ultra-thin pure silver foil strip and manufacturing method thereof Technical field

The invention relates to the technical field of metal foil processing, in particular to a wide-width ultra-thin pure silver foil strip and a manufacturing method thereof.

Background technique

Sterling silver is a beautiful silver-white metal with good ductility and its highest conductivity and heat transfer among all metals. Silver is commonly used to make highly sensitive physical instrument components, automation devices, rockets, submarines, computers, nuclear devices, and communication systems, all of which have a large number of contact points made of silver. Since the price of silver is relatively expensive, the cost of using silver is actually reduced, and silver is generally processed into a silver foil. The processing method of silver foil is hand-made earlier, and the hand-made process can only produce small-sized pure silver foil, which is high in production cost and cannot be made into a strip, which restricts the use range of the silver foil.

At present, there is a technology for processing silver foil by mechanical equipment. This technology usually uses a cold rolling process. For example, Chinese Patent No. CN 102861517A discloses a method for preparing a cold-rolled ultra-thin palladium-silver alloy film which is repeatedly rolled by a two-roll cold rolling mill until a cold-rolled ultra-thin palladium having a thickness of 2 μm is obtained. - Silver alloy film, which needs to be annealed after each rolling three times; electroless plating repair of the ultra-thin palladium-silver alloy film obtained by cold rolling, and the obtained cold-rolled ultra-thin palladium-silver alloy film is repaired by electroless plating No defects afterwards, high hydrogen permeability and selectivity. In the prior art, a method of manufacturing an aluminum foil by a rolling process using mechanical equipment can only produce a pure silver foil tape having a width of 160 mm or less and a thickness of 50 μm or more. Since the rolling process has many passes per stage, the number of rolling times is large, which leads to complicated process. In addition, multiple oxygen-free vacuum annealing is required, which results in limited width of the silver foil, thick foil strip thickness and low yield. The high cost per unit area of the foil material increases the production cost, thereby limiting the industrial production application of the silver foil strip.

Summary of the invention

In view of the above, the present invention provides a method for manufacturing a wide-width ultra-thin pure silver foil tape, which is simple in manufacturing method, and the pure silver foil thus obtained has a wide bandwidth and an ultra-thin.

A method for manufacturing a wide and ultra-thin pure silver foil strip, comprising the steps of:

(1) smelting pure silver material into pure silver liquid;

(2) the pure silver liquid is melted, and is drawn at 700 to 960 ° C to form a silver plate having a width of 200 to 600 mm and a thickness of 8 to 10 mm, and the rolling is performed during the drawing;

(3) rough-rolling the silver plate using a rough rolling apparatus to form a silver strip having a thickness of 2 to 3 mm;

(4) the silver strip is subjected to medium rolling using a medium rolling apparatus to form a silver strip having a thickness of 0.5 to 0.8 mm;

(5) The silver strip processed by the step (4) is subjected to finish rolling using a finishing rolling apparatus to form a silver strip having a thickness of 0.1 to 0.2 mm;

(6) annealing the silver ribbon treated by the step (5);

(7) the silver strip processed by the step (6) is subjected to foil rolling to a predetermined thickness using a foil rolling apparatus;

(8) The silver ribbon treated in the step (7) is subjected to post treatment.

In the above method, the smelting apparatus may employ commercially available equipment commonly used in the art, such as a crucible melting furnace. The temperature of the smelting is such that the solid silver material is melted into a liquid, that is, the temperature is controlled not lower than the melting point. The temperature of the smelting in the present invention is not particularly limited and may be, for example, but not limited to, 1150 to 1180 °C. In the smelting process, when the pure silver material is all turned into silver liquid, a heat preservation stage can be implemented. There is no special requirement for the heat preservation time, for example, 1 to 2 hours.

The melt refers to a molten state, an amorphous state, which is generally a "soft" state in which liquid silver is not fully solidified and cooled. Rolling is facilitated in this state. The formation of a melt of pure silver liquid can be carried out in a crystallizer.

Compared with the simple cold rolling in the prior art, the pulling in the present application can avoid the phenomenon of fracture of the processed material caused by the pressing force in the cold rolling process, thereby ensuring that the silver plate obtained by the processing is longer, generally Several kilometers are even longer. The temperature to be pulled should be at a temperature required to maintain at least pure silver as a melt, preferably but not limited to 700 to 960 °C. The rate of pulling is preferably 2 to 3 m/h. The rolling used in the drawing process is hot rolling, and the relevant process parameters of the hot rolling can be carried out using process parameters well known to those skilled in the art.

The pass rate of the rough rolling is preferably 35 to 50%, and the pass rate is preferably successively decreased throughout the rough rolling process. Rough rolling equipment has no stringent requirements, such as a commercially available two-roll roughing mill.

The pass processing rate of the medium rolling is preferably 30 to 50%, and the pass processing rate is preferably successively decreased throughout the middle rolling process. There are no stringent requirements for medium rolling equipment, such as the commercially available four-roll mill.

The pass processing rate of the finish rolling is preferably 25 to 35%, and the pass processing rate is preferably successively decreased throughout the middle rolling process. There are no stringent requirements for medium rolling equipment, such as the commercially available six-high finishing mill.

The annealing temperature is preferably 550 to 580 °C. The processes associated with the annealing operation, such as the annealed medium and the annealing time, can be performed according to conventional annealing techniques and will not be described herein.

The pass rate of the foil rolling is preferably 25 to 40%. There are no stringent requirements for foil rolling equipment, such as commercially available high-precision foil mills. The rolling rate of the foil rolling is preferably 50 to 200 m/min. The thickness of the foil roll is designed to the thickness of the desired product, and the thickness achieved by the method of the present invention can be as large as 0.01 mm, which is thinner than in the prior art.

Post-treatment mainly includes surface treatment and subsequent slitting, packaging, and the like. The surface treatment can include passivating and cleaning the surface in order from first to last. Passivation and cleaning can be carried out using surface treatment techniques conventional in the art. Due to space limitations, it is not detailed.

Another aspect of the invention provides a wide-width ultra-thin pure silver foil strip having a width and an ultra-thin thickness.

A pure silver foil tape obtained by the above production method has a width of 200 to 600 mm and a thickness of 0.01 to 0.05 mm.

Due to its large width and small thickness, the amount of silver used per unit area of the foil strip is greatly reduced, which greatly saves costs.

The method for producing a pure silver foil tape of the present invention employs a pulling step which can avoid the phenomenon of fracture of the processed material due to the pressing force in the cold rolling process, thereby ensuring a longer silver plate obtained by the processing. The whole rolling process only needs rough rolling, medium rolling, finishing rolling and foil rolling, and the rolling process is relatively simple; only one annealing is required before the rolling, which avoids the numerous anaerobic vacuum annealing in the prior art. The process of the invention is simple, and the obtained pure silver foil has a wide bandwidth and an ultra-thin. In addition, the processing accuracy of the entire manufacturing method is also high.

detailed description

The technical solution of the present invention will be further described below in conjunction with the embodiments.

Embodiment 1 In this example, the manufacturing method sequentially includes the following steps:

(1), smelting: the pure silver material is put into the crucible melting furnace for melting, the melting temperature is 1150 ° C, and the temperature is kept for 2 hours;

(2), pulling: the pure silver liquid is controlled by the crystallizer at the melt temperature, and is drawn and solidified at 960 ° C into a silver strip with a width of 200 mm, the strip thickness is 8 mm, and the pulling speed is 2 meters per hour;

(3), rough rolling: using a two-roll rough rolling mill to roll the silver strip into a silver strip with a thickness of 2 mm, the pass processing rate is successively decreased, and the processing rate is 35% to 50%;

(4) Medium rolling: a 2 mm silver strip is rolled into a 0.5 mm silver strip using a four-roll mill, and the pass processing rate is 30%, which is successively decreased;

(5) Finish rolling: a 0.5 mm silver strip is rolled into a 0.1 mm silver strip using a six-roll finishing mill, and the pass processing rate is 25%, which is successively decreased;

(6), trimming annealing: edge-annealing of the finish-rolled silver strip, annealing temperature 550 ° C;

(7), foil rolling: using a high-precision foil rolling unit for foil rolling of 0.1mm silver strip, the rolling thickness is determined according to product design requirements, the minimum can reach 0.01mm. The pass processing rate is 25%%, and the multi-pass, small-pass indentation rolling is used, and the oil is lubricated and cooled. Rolling speed of 50 meters per minute;

(8), passivation: surface passivation treatment of the formed foil strip to prevent oxidation;

(9), cleaning and slitting: surface cleaning of the foil strip product, removing oil and other impurities on the surface of the product, and then cutting according to the actual use width;

(10), packaging: finished product packaging into the warehouse.

Example 2

In this example, the manufacturing method sequentially includes the following steps:

(1), smelting: the pure silver material is put into the crucible melting furnace for melting, the melting temperature is 1180 ° C, and the temperature is kept for 1 hour;

(2), pulling: the pure silver liquid is controlled by the crystallizer at the melt temperature, and is drawn and solidified at 960 ° C into a silver strip with a width of 600 mm, the strip thickness is 10 mm, and the pulling speed is 3 meters per hour;

(3), rough rolling: using a two-roll rough rolling mill to roll the silver strip into a silver strip with a thickness of 3 mm, the pass processing rate is successively decreased, and the processing rate is 50%;

(4) Medium rolling: a 3 mm silver strip is rolled into a 0.8 mm silver strip using a four-roll mill, and the pass processing rate is 50%, which is successively decreased;

(5) Finishing rolling: a 0.8 mm silver strip is rolled into a 0.2 mm silver strip using a six-roll finishing mill, and the pass processing rate is 35%, which is successively decreased;

(6), trimming annealing: edge-annealing of the finish-rolled silver strip, annealing temperature 580 ° C;

(7), foil rolling: using a high-precision foil rolling mill for the 0.2mm silver strip for foil rolling, the rolling thickness is determined according to product design requirements, the minimum can reach 0.01mm. The pass processing rate is 40%, and the multi-pass, small-pass indentation rolling is used, and the oil is lubricated and cooled. Rolling speed of 200 meters per minute;

(8), passivation: surface passivation treatment of the formed foil strip to prevent oxidation;

(9), cleaning and slitting: surface cleaning of the foil strip product, removing oil and other impurities on the surface of the product, and then cutting according to the actual use width;

(10), packaging: finished product packaging into the warehouse.

Example 3

In this example, the manufacturing method sequentially includes the following steps:

(1), smelting: the pure silver material is put into the crucible melting furnace for melting, the melting temperature is 1165 ° C, and the heat is kept for 1.5 hours;

(2), pulling: the pure silver liquid is controlled by the crystallizer at the melt temperature, and is drawn and solidified at 960 ° C into a silver strip with a width of 400 mm, the strip thickness is 9 mm, and the pulling speed is 2.5 meters per hour;

(3), rough rolling: using a two-roll rough rolling mill to roll the silver strip into a silver strip with a thickness of 2.5 mm, the processing rate of the pass is successively decreased, and the processing rate is 40%;

(4), medium rolling: using a 2.5-inch silver belt of a four-roll mill to roll into a 0.65mm silver belt, the pass processing rate is 40%, which is successively decreased;

(5) Finishing: The 0.65mm silver strip is rolled into a 0.15mm silver strip using a six-roll finishing mill, and the pass processing rate is 30%, which is successively decreased;

(6), trimming annealing: trimming and annealing the finish rolled silver strip, the annealing temperature is 550-580 degrees;

(7), foil rolling: using a high-precision foil rolling mill for foil rolling of 0.15mm silver strip, the rolling thickness is determined according to product design requirements, the minimum can reach 0.01mm. The pass processing rate is 30%, and the multi-pass, small-pass indentation rolling is used, and the oil is lubricated and cooled. Rolling speed of 120 meters per minute;

(8), passivation: surface passivation treatment of the formed foil strip to prevent oxidation;

(9), cleaning and slitting: surface cleaning of the foil strip product, removing oil and other impurities on the surface of the product, and then cutting according to the actual use width;

(10), packaging: finished product packaging into the warehouse.

Example 4

In this example, the manufacturing method sequentially includes the following steps:

(1), smelting: the pure silver material is put into the crucible melting furnace for melting, the melting temperature is 1165 ° C, and the temperature is kept for 2 hours;

(2), pulling: the pure silver liquid is controlled by the crystallizer at the melt temperature, and is drawn and solidified at 960 ° C into a silver strip with a width of 600 mm, the strip thickness is 8 mm, and the pulling speed is 2.5 meters per hour;

(3), rough rolling: using a two-roll rough rolling mill to roll the silver strip into a silver strip with a thickness of 2 mm, the pass processing rate is successively decreased, and the processing rate is 40%;

(4) Medium rolling: a 2 mm silver strip is rolled into a 0.5 mm silver strip using a four-roll mill, and the pass processing rate is 40%, which is successively decreased;

(5) Finish rolling: a 0.5 mm silver strip is rolled into a 0.1 mm silver strip using a six-roll finishing mill, and the pass processing rate is 30%, which is successively decreased;

(6), trimming annealing: edge-annealing of the finish-rolled silver strip, annealing temperature 565 ° C;

(7), foil rolling: using a high-precision foil rolling unit for foil rolling of 0.1mm silver strip, the rolling thickness is determined according to product design requirements, the minimum can reach 0.01mm. The pass processing rate is 30%, and the multi-pass, small-pass indentation rolling is used, and the oil is lubricated and cooled. Rolling speed of 120 meters per minute;

(8), passivation: surface passivation treatment of the formed foil strip to prevent oxidation;

(9), cleaning and slitting: surface cleaning of the foil strip product, removing oil and other impurities on the surface of the product, and then cutting according to the actual use width;

(10), packaging: finished product packaging into the warehouse.

The manufacturing method of the present invention has the following advantages:

1. The width of the pure silver foil strip is large, and the pure silver foil strip with the width of 200mm or more and 600mm or less can be produced at one time. The length of the foil strip can reach several kilometers and above at a time;

2, the thickness of pure silver foil tape is greatly reduced, the thickness can be as low as 10um ~ 50um, and the precision is high, the foil tape thickness tolerance is less than 3%;

3. The amount of silver used per unit area of the foil strip is greatly reduced. Taking the thickness of the 15um foil as an example, the amount of silver used per square meter is only 157.5g, and the amount of silver used for the foil of 50um thickness is 524.5g;

4. Silver is the best electrical and thermal conductor among all metals. The ultra-thin wide-format silver foil makes the amount of silver per unit area of pure silver foil tape drop drastically, which brings about a significant drop in production costs and greatly expands. The use of silver foil tapes has an irreplaceable position in the technical field where the requirements for ductility, heat dissipation and electrical conductivity are extremely high, such as electronics, IT, LED lighting, special cables, aerospace, etc. Widely used in civil home decoration, handicrafts and other industries.

Since the numerical ranges of the various process parameters involved in the present invention are not fully exemplified in the above embodiments, those skilled in the art can fully imagine that the present invention can be implemented by any numerical value falling within the above numerical range. It is of course also intended to include any combination of specific values within a range of values. Here, For the sake of consideration, embodiments that give specific values within a certain one or more numerical ranges are omitted, and this should not be considered as an insufficient disclosure of the technical solutions of the present invention.

The Applicant declares that the present invention illustrates the detailed process equipment and process flow of the present invention by the above embodiments, but the present invention is not limited to the above detailed process equipment and process flow, that is, does not mean that the present invention must rely on the above detailed process equipment and The process can only be implemented. It should be apparent to those skilled in the art that any modifications of the present invention, equivalent substitution of the various materials of the products of the present invention, addition of auxiliary components, selection of specific means, and the like, are all within the scope of the present invention.

Claims (10)

A method for manufacturing a wide ultra-thin pure silver foil strip, comprising the steps of: (1) smelting pure silver material into pure silver liquid; (2) the pure silver liquid is melted, and is drawn at 700 to 960 ° C to form a silver plate having a width of 200 to 600 mm and a thickness of 8 to 10 mm, and the rolling is performed during the drawing; (3) rough-rolling the silver plate using a rough rolling apparatus to form a silver strip having a thickness of 2 to 3 mm; (4) the silver strip is subjected to medium rolling using a medium rolling apparatus to form a silver strip having a thickness of 0.5 to 0.8 mm; (5) The silver strip processed by the step (4) is subjected to finish rolling using a finishing rolling apparatus to form a silver strip having a thickness of 0.1 to 0.2 mm; (6) annealing the silver ribbon treated by the step (5); (7) the silver strip processed by the step (6) is subjected to foil rolling to a predetermined thickness using a foil rolling apparatus; (8) The silver ribbon treated in the step (7) is subjected to post treatment. The method according to claim 1, wherein the temperature of the smelting in the step (1) is from 1150 to 1180 ° C, and the holding time in the smelting process is from 1 to 2 h. The manufacturing method according to claim 1, wherein the pulling rate in the step (2) is 2 to 3 m/h. The manufacturing method according to claim 1, wherein the pass rolling processing rate of the rough rolling in the step (3) is 35 to 50%; Preferably, the rough rolling equipment is a two-roll roughing mill. The manufacturing method according to claim 1, wherein the pass processing rate of the medium rolling in the step (4) is 30 to 50%; Preferably, the medium rolling equipment is a four-high mill. The manufacturing method according to claim 1, wherein the finishing rate of the finishing rolling in the step (5) is 25 to 35%; Preferably, the finishing equipment is a six-high finishing mill. The manufacturing method according to claim 1, wherein the annealing temperature in the step (6) is 550 to 580 ° C; Preferably, the trimming is performed prior to the annealing. The manufacturing method according to claim 1, wherein the pass rate of the foil rolling in the step (7) is 25 to 40%; Preferably, the rolling speed of the foil rolling is 50 to 200 m / min; Preferably, the foil rolling equipment is a high precision foil rolling mill. The manufacturing method according to claim 1, wherein the post-processing in the step (8) comprises first passivating and cleaning the surface from first to last; Preferably, the cleaning further comprises slitting and cutting. A pure silver foil tape obtained by the production method according to claim 1, which has a width of 200 to 600 mm and a thickness of 0.01 to 0.05 mm.