CN115430710A - Rolling method of large-size molybdenum-niobium target blank - Google Patents

Abstract

The invention relates to a rolling method of a large-size molybdenum-niobium target blank, which comprises the following steps: sequentially cogging and rolling the molybdenum niobium target blank; the cogging temperature is 1100-1300 ℃. According to the invention, by adjusting parameters such as heating temperature, heat preservation time, rolling mode, pressing amount, rolling speed and the like of cogging and rolling, on the basis of the existing equipment, the cracking probability of the molybdenum-niobium target blank in the rolling process is reduced, the yield of the product is improved, and the requirement of sputtering target materials for panel display is met.

Description

Rolling method of large-size molybdenum-niobium target blank

Technical Field

The invention belongs to the technical field of target processing, and particularly relates to a rolling method of a large-size molybdenum-niobium target blank.

Background

With the development of the flat panel display industry, the requirements on wiring materials and barrier layer materials used in the flat panel display are more and more strict. As display panels are becoming larger, the trend of conductive materials from aluminum to copper is developing, and molybdenum, molybdenum alloys and copper have excellent adhesion and are beneficial to the stability of barrier layers, and therefore, molybdenum alloys are mainly used as underlayers or capping layers for copper, to control the reflectivity and to provide protection against corrosion during photolithography.

Currently, the large-sized liquid crystal panel generally uses molybdenum or molybdenum-niobium target material as the barrier layer or shielding material. Particularly, the large-size molybdenum or molybdenum-niobium target material is easy to deform after being pressed and sintered, and due to the immaturity and uncertainty of the rolling process, such as the immaturity and uncertainty of each heating number, the deformation amount of each pass rolling, the rolling speed, the cogging and rolling temperature, the corresponding heat preservation time and the like, the uncertainty in the rolling process is greatly increased, the plate surface bending is easy to occur in the rolling process, even the rolling cracking or material blocking occurs, the operation difficulty is increased, the subsequent rolling task is influenced, the loss of the plate material is overlarge to a certain extent, the yield is reduced, and even the waste product occurs.

CN113637945A discloses a rolling preparation method of a large-size molybdenum-niobium alloy target, which comprises the following steps: the method comprises the steps of proportioning, mixing and evenly mixing the alloy raw materials of the target material according to a proportion, carrying out cold isostatic pressing, bagging, vacuumizing, exhausting, hot isostatic pressing, rolling with a belt sleeve, annealing and leveling, removing the sleeve, and processing to a specified size, wherein the hot isostatic pressing temperature is 1250-1400 ℃, the temperature is kept for 2-4h, the opening temperature of the rolling with the belt sleeve is 1400-1450 ℃, the cogging deformation is 20-30%, and the temperature is reduced and the rolling is carried out until the final rolling temperature is 1250 ℃, and the pass deformation is 15-30%. The method adopts a jacket rolling mode, the rolling cogging temperature exceeds 1400 ℃, the method can cause great abrasion to a rolling mill, and the surface state of a rolled product is poor.

CN102534519A discloses a preparation method of a large-size molybdenum plate for a sputtering target of an LCD flat-panel display, which comprises the following steps: 1) Uniformly coating an anti-oxidation coating on the surface of a fine plate blank pressed and sintered by a conventional method; 2) Coating the molybdenum plate blank coated with the antioxidant coating by using a steel sheath; 3) Rolling the molybdenum plate blank coated with the steel sheath for one time, and then placing the molybdenum plate blank on a cooling bed for cooling; 4) Rolling the cooled molybdenum plate blank to a thickness of 19-24 mm (including a steel sheath); 5) Leveling the rolled molybdenum plate blank, removing the steel sheath, and cutting to obtain a semi-finished molybdenum plate; 6) And carrying out vacuum heat treatment on the semi-finished molybdenum plate to obtain the large-size molybdenum plate for the sputtering target of the LCD flat-panel display. The method has complex flow and is easy to cause resource waste through brushing the coating and rolling the strip steel by sheathing.

Therefore, how to provide a rolling method of a large-size molybdenum niobium target blank, which avoids the cracking phenomenon during the rolling of the molybdenum niobium target blank and reduces the production cost of the product at the same time is a problem to be solved urgently by technical personnel in the field.

Disclosure of Invention

The invention aims to provide a rolling method of a large-size molybdenum-niobium target blank, which avoids the cracking phenomenon of the molybdenum-niobium target blank in the rolling process, reduces the production cost and improves the yield of the target blank.

In order to achieve the technical effect, the invention adopts the following technical scheme:

the invention provides a rolling method of a large-size molybdenum-niobium target blank, which comprises the following steps: sequentially cogging and rolling the molybdenum niobium target blank;

the temperature of the above-mentioned cogging may be 1100 to 1300 ℃, for example, 1100 ℃, 1120 ℃, 1140 ℃, 1160 ℃, 1180 ℃, 1200 ℃, 1220 ℃, 1240 ℃, 1260 ℃, 1280 ℃ or 1300 ℃, but is not limited to the above-mentioned values, and other values not shown in the numerical range are also applicable.

According to the invention, by adjusting the cogging and rolling temperatures and the rolling mode, on the basis of the existing equipment, the cracking probability of the molybdenum-niobium target blank in the rolling process is reduced, the yield of the product is improved, and the requirement of the sputtering target material for flat panel display is met.

In a preferred embodiment of the present invention, the holding time for the cogging is 30 to 60min, and may be, for example, 30min, 35min, 40min, 45min, 50min, 55min, or 60min, but the holding time is not limited to the above-mentioned values, and other values not shown in the above-mentioned value range are also applicable.

The cogging speed is preferably 20 to 25m/min, and may be, for example, 20m/min, 21m/min, 22m/min, 23m/min, 24m/min, or 25m/min, but is not limited to the recited values, and other values not recited in the range of values are also applicable.

In a preferred embodiment of the present invention, the total pressing amount of the cogging may be 40% to 55%, for example, 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, or 55%, but the present invention is not limited to the above-mentioned values, and other values not shown in the numerical range are also applicable.

Preferably, the number of the cogging passes is 2 to 4, and may be, for example, 2, 3, or 4, but the present invention is not limited to the above-mentioned values, and other values not shown in the numerical range are also applicable, and preferably 3.

In the invention, if the selection of the cogging pass is not reasonable, the single-pass pressing amount is influenced, and the cogging is difficult to be rolled to a proper size.

Preferably, the pressing amount of the single pass of the cogging is 17 to 22%, for example, 17%, 18%, 19%, 20%, 21%, 22%, etc., but the number is not limited to the recited number, and other numbers not recited in the range of the number are also applicable.

In the present invention, the pressing amount of a single pass is the amount of change in thickness before and after single-pass cogging, and therefore, the total pressing amount = 1-the thickness after cogging, for example, the total pressing amount =1- (1-0.22) ³ 。

In the invention, if the pressing amount of a single pass of cogging is too low, the target blank is cracked due to large deformation of the surface layer and basically no plastic deformation of the core part; if the pressing amount of a single pass of cogging is too high and the deformation is too large, the target billet is difficult to bite, the rolling capability of the rolling mill is greatly tested, and the rolling mill is easy to damage.

As a preferable technical scheme of the present invention, the heating and heat-preserving treatment is performed after each pass of the cogging.

Preferably, the heat preservation temperature is 1120-1200 ℃, for example 1120 ℃, 1130 ℃, 1140 ℃, 1150 ℃, 1160 ℃, 1170 ℃, 1180 ℃, 1190 ℃ or 1200 ℃, but not limited to the values listed, and other values not listed in the numerical range are also applicable.

Preferably, the time of the heat-preservation treatment is 10 to 15min, for example, 10min, 11min, 12min, 13min, 14min or 15min, but the heat-preservation treatment is not limited to the recited values, and other values not recited in the numerical range are also applicable.

In the invention, the rolled steel is sent into a heating furnace for heat preservation for 10-15min after single pass rolling, the temperature of the target blank is ensured to be kept above 1100 ℃, and the phenomenon of opening of the end when the target blank is rolled by cooling is avoided.

In a preferred embodiment of the present invention, the rolling temperature is 1150-1250 ℃, for example 1150 ℃, 1160 ℃, 1170 ℃, 1180 ℃, 1190 ℃, 1200 ℃, 1220 ℃, 1240 ℃ or 1250 ℃, but the rolling temperature is not limited to the above-mentioned values, and other values not listed in the range of values are also applicable.

Preferably, the holding time for the rolling is 10-20min, for example, 10min, 12min, 14min, 16min, 18min or 20min, but the rolling is not limited to the recited values, and other values not recited in the numerical range are also applicable.

The rolling speed is preferably 40 to 50m/min, and may be, for example, 40m/min, 42m/min, 44m/min, 46m/min, 48m/min, or 50m/min, but is not limited to the values listed, and other values not listed in the numerical range are also applicable.

In the invention, the rolling speed is higher than the cogging speed, and the subsequent rolling speed is required to be higher than the cogging speed in order to ensure that the temperature of the target billet does not drop too much in the whole rolling process because the length of the target billet in the subsequent rolling process is larger than that in the cogging process.

In a preferred embodiment of the present invention, the total rolling reduction is 35% to 50%, for example, 35%, 37%, 40%, 42%, 44%, 46%, 48%, or 50%, but the present invention is not limited to the above-mentioned values, and other values not listed in the numerical range are also applicable.

In a preferred embodiment of the present invention, the rolling passes are 2 to 6, preferably 4.

In the invention, the total rolling pass is set according to the thickness required by the product, but not more than six passes.

Preferably, the rolling reduction in a single pass of the rolling is 10% to 15%, for example 10%, 11%, 12%, 13%, or 15%, but is not limited to the recited values, and other values not recited within the range of values are equally applicable.

In the present invention, the rolling reduction per single pass is the amount of change in thickness before and after single pass rolling, so the total rolling reduction = 1-thickness after rolling.

In the invention, if the reduction of a single pass of rolling is too low, the rolling passes are too many, and the processing efficiency is influenced; if the pressing amount of a single pass of rolling is too high, the target blank is difficult to bite, the rolling force is easy to exceed the limit, and equipment is easy to damage.

As a preferable technical scheme of the invention, the heating and heat preservation treatment is carried out after every two times of rolling.

Preferably, the heat-insulating treatment temperature is 1150-1200 ℃, for example 1150 ℃, 1160 ℃, 1170 ℃, 1180 ℃, 1190 ℃ or 1200 ℃, but not limited to the values listed, and other values not listed in the numerical range are also applicable.

Preferably, the time of the heat-preservation treatment is 10 to 20min, for example, 10min, 12min, 14min, 16min, 18min or 20min, but the heat-preservation treatment is not limited to the recited values, and other values not recited in the numerical range are also applicable.

In the invention, in the rolling process, the target blank is sent into a heating furnace for heat preservation for 10-20min after every two times, the temperature of the target blank is ensured to be kept above 1100 ℃, and the side edge of the target blank is prevented from generating inward-expanding cracks in the rolling process.

As a preferable technical scheme of the invention, the molybdenum-niobium target blank is obtained by hot isostatic pressing and capsule removal.

Preferably, the molybdenum niobium target blank has a length of 1000 to 1500mm, for example 1000mm, 1100mm, 1200mm, 1300mm, 1400mm or 1500mm, but the values are not limited to the recited values, and other values not recited in the range of values are also applicable.

Preferably, the width of the molybdenum niobium target blank is 250-400mm, for example 250mm, 300mm, 350mm or 400mm, but not limited to the recited values, and other values not recited in the range of values are also applicable.

Preferably, the thickness of the molybdenum niobium target blank is 100-150mm, for example, 100mm, 110mm, 120mm, 130mm, 140mm or 150mm, but the thickness is not limited to the recited values, and other values not recited in the range of values are also applicable.

In the invention, the length of the large-size molybdenum-niobium target blank is more than 1000mm, the width is more than 250mm, and the thickness is more than 100mm.

As a preferable embodiment of the present invention, the rolling method includes the steps of:

(1) After hot isostatic pressing, removing the sheath to obtain a first molybdenum niobium target blank;

(2) Heating the first molybdenum niobium target blank in the step (1) to 1100-1300 ℃, preserving heat for 30-60min, and cogging at a speed of 20-25m/min, wherein the total pressing amount is 40% -55%; the cogging pass is 2-4 times, the pressing amount of a single pass is 17% -22%, and after each pass, the molybdenum niobium target blank is heated to 1120-1200 ℃ and is kept for 10-15min to obtain a second molybdenum niobium target blank;

(3) Heating the second molybdenum niobium target blank in the step (2) to 1150-1250 ℃, preserving heat for 10-20min, and rolling at the speed of 40-50m/min, wherein the total pressing amount is 35% -50%; the rolling passes are 2-6 times, the pressing amount of a single pass is 10% -15%, and after every two passes, the molybdenum niobium target blank is heated to 1150-1200 ℃ and is kept warm for 10-20min, so that the molybdenum niobium target blank is obtained.

The numerical ranges set forth herein include not only the recited values but also any values between the recited numerical ranges not enumerated herein, and are not intended to be exhaustive or otherwise clear from the intended disclosure of the invention in view of brevity and clarity.

Compared with the prior art, the invention has the following beneficial effects:

the rolling method provided by the invention comprises the steps of cogging and rolling which are sequentially carried out, and the cracking probability of the molybdenum-niobium target blank in the rolling process is reduced on the basis of the existing equipment by adjusting the heating temperature, the heat preservation time, the rolling mode, the pressing amount, the rolling speed and other parameters of cogging and rolling, so that the yield of the product is improved, and the requirement of a sputtering target material for flat panel display is met; the preparation method does not need complex process conditions, and has low production cost and wide applicability.

Detailed Description

For the purpose of facilitating an understanding of the present invention, the following examples are set forth herein. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitation of the present invention.

Example 1

The embodiment provides a rolling method of a large-size molybdenum-niobium target blank, which comprises the following steps:

(1) Hot isostatic pressing, after removing the sheath, polishing each edge of the target blank, and removing the pits to obtain a first molybdenum-niobium target blank with the length of 1200mm, the width of 300mm and the thickness of 120mm;

(2) Heating the first molybdenum niobium target blank in the step (1) to 1200 ℃, preserving heat for 50min, and cogging at a speed of 23m/min, wherein the total cogging pressing amount is 52.5%; the cogging pass is 3 times, the pressing amount of a single pass is 22%, and after each pass, the molybdenum niobium target blank is sent into a heating furnace to be heated to 1150 ℃ and is kept for 12min to obtain a second molybdenum niobium target blank;

(3) Heating the second molybdenum niobium target blank in the step (2) to 1200 ℃, preserving heat for 15min, and rolling at the speed of 45m/min, wherein the total rolling reduction is 47.8%; the rolling passes are 4 times, the pressing amount of a single pass is 15%, and after every two passes, the molybdenum niobium target blank is sent into a heating furnace to be heated to 1170 ℃ and is kept warm for 15min, so that the molybdenum niobium target blank is obtained.

Example 2

The embodiment provides a rolling method of a large-size molybdenum-niobium target blank, which comprises the following steps:

(1) Hot isostatic pressing, after removing the sheath, polishing each edge of the target blank, and removing the pits to obtain a first molybdenum-niobium target blank with the length of 1000mm, the width of 300mm and the thickness of 100mm;

(2) Heating the first molybdenum niobium target blank in the step (1) to 1100 ℃, preserving heat for 60min, and cogging at the speed of 25m/min, wherein the total cogging pressing amount is 42.8%; the cogging pass is 3 times, the pressing amount of a single pass is 17%, and after each pass, the molybdenum niobium target blank is sent into a heating furnace to be heated to 1120 ℃ and is subjected to heat preservation for 15min to obtain a second molybdenum niobium target blank;

(3) Heating the second molybdenum niobium target blank in the step (2) to 1150 ℃, preserving heat for 20min, and rolling at the speed of 40m/min, wherein the total rolling reduction is 46.9%; the rolling passes are 6, the pressing amount of a single pass is 10%, and after every two passes, the molybdenum niobium target blank is sent into a heating furnace to be heated to 1150 ℃ and is subjected to heat preservation for 20min to obtain the molybdenum niobium target blank.

Example 3

The embodiment provides a rolling method of a large-size molybdenum-niobium target blank, which comprises the following steps:

(1) Hot isostatic pressing, namely after removing the sheath, polishing each edge of the target blank, and removing the pits to obtain a first molybdenum-niobium target blank with the length of 1500mm, the width of 400mm and the thickness of 150mm;

(2) Heating the first molybdenum niobium target blank in the step (1) to 1300 ℃, preserving heat for 30min, and cogging at the speed of 20m/min, wherein the total cogging pressing amount is 48.8%; the cogging pass is 3 times, the pressing amount of a single pass is 20%, and after each pass, the molybdenum niobium target blank is sent into a heating furnace to be heated to 1200 ℃ and is kept warm for 10min to obtain a second molybdenum niobium target blank;

(3) Heating the second molybdenum niobium target blank in the step (2) to 1250 ℃, preserving heat for 10min, and rolling at the speed of 50m/min, wherein the total rolling reduction is 42.7%; the rolling passes are 4 times, the pressing amount of a single pass is 13%, and after every two passes, the molybdenum-niobium target blank is sent into a heating furnace to be heated to 1200 ℃ and is kept for 10min to obtain the molybdenum-niobium target blank.

Example 4

This example provides a method for rolling a large molybdenum niobium target blank under the same conditions as in example 1 except that the reduction amount in a single pass of step (2) is 12%.

Example 5

This example provides a method for rolling a large molybdenum niobium target blank under the same conditions as in example 1 except that the reduction amount in the single pass of step (2) is 30%.

Example 6

This example provides a rolling method of a large-size molybdenum niobium target blank, which is the same as example 1 except that the molybdenum niobium target blank is not sent to a heating furnace for heat preservation after each pass in step (2).

Example 7

This example provides a rolling method of a large molybdenum niobium target blank, which is the same as that of example 1 except that the rolling in step (3) is heated to 1100 ℃.

Example 8

This example provides a rolling method of a large molybdenum niobium target blank, which is the same as that of example 1 except that the step (3) is rolled and heated to 1350 ℃.

Example 9

This example provides a rolling method of a large-sized molybdenum niobium target blank, which is the same as that of example 1 except that the rolling is performed at a speed of 23m/min in step (3).

Example 10

This example provides a rolling method of a large-sized molybdenum niobium target blank, which is the same as that of example 1 except that the rolling is performed at a speed of 60m/min in step (3).

Example 11

This example provides a rolling method of a large molybdenum-niobium target blank, which is the same as that of example 1 except that the reduction amount in a single pass of step (3) is 25%.

Example 12

This example provides a rolling method of a large-size molybdenum niobium target blank, which is the same as example 1 except that the molybdenum niobium target blank is not sent to the heating furnace for heat preservation after every two passes in step (3).

Comparative example 1

This comparative example provides a rolling process for a large molybdenum niobium target billet, the conditions being the same as in example 1 except that the cogging in step (2) was heated to 1000 ℃.

Comparative example 2

This comparative example provides a rolling process for a large molybdenum niobium target billet, under the same conditions as in example 1 except that the cogging in step (2) was heated to 1400 ℃.

The molybdenum niobium target blanks rolled in the above examples and comparative examples were subjected to the tests of the density, the presence or absence of cracks in the target blanks, and the internal structure of C-Scan flaw detection, and the results are shown in table 1. The density detection method comprises the following steps: measuring the density by an Archimedes drainage method; detecting whether the appearance of the target blank has cracks by naked eyes; the C-Scan flaw detection method comprises the following steps: and (4) carrying out C-Scan flaw detection by adopting an ultrasonic flaw detection detector.

TABLE 1

As can be seen from table 1, the following,

(1) The molybdenum-niobium target blank obtained by the rolling method provided by the embodiment 1-3 of the invention has the density of more than 98%, has no crack on the appearance, and has no abnormal defect in the internal structure of the C-Scan flaw detection;

(2) As can be seen from the comparison between the embodiment 1 and the embodiments 6 and 12, when the target blank is not subjected to heating and heat preservation treatment in each pass of rolling process in cogging or rolling, the target blank is cracked, and abnormal defects are found in internal tissues of the C-Scan flaw detection;

(3) As can be seen from comparison between example 1 and examples 7-8, when the rolling heating temperature is too low, the target blank has higher hardness and higher deformation difficulty, so that the target blank cracks; when the rolling heating temperature is too high, the target blank material is in a recrystallization state, the plasticity of the target blank material is reduced, and cracks can also appear in the target blank;

(4) As can be seen from the comparison between example 1 and comparative examples 1-2, when the cogging heating temperature is too low, the hardness of the target blank is high, the deformation difficulty is high, the target blank is difficult to bite, and severe cracking occurs; when the cogging heating temperature is too high, the target blank material is in a recrystallized state, and the strongly deformed cell boundary structure may contain crack nuclei, resulting in cracking of the target blank.

The applicant declares that the above description is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and it should be understood by those skilled in the art that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention disclosed herein fall within the scope and disclosure of the present invention.

Claims (10)

1. A rolling method of a large-size molybdenum-niobium target blank is characterized by comprising the following steps: sequentially cogging and rolling the molybdenum niobium target blank;

the cogging temperature is 1100-1300 ℃.

2. The rolling method according to claim 1, characterized in that the holding time for the cogging is 30-60min;

preferably, the cogging speed is 20-25m/min.

3. Rolling process according to claim 1 or 2, characterised in that the total reduction in cogging is between 40% and 55%;

preferably, the number of the cogging passes is 2-4;

preferably, the reduction amount of a single pass of the cogging is 17% -22%.

4. The rolling method according to claim 3, wherein each pass of the cogging is followed by a heat-holding treatment;

preferably, the temperature of the heating and heat preservation treatment is 1120-1200 ℃;

preferably, the time of the heating and heat preservation treatment is 10-15min.

5. A rolling method according to any one of claims 1 to 4, characterised in that the rolling temperature is 1150-1250 ℃;

preferably, the heat preservation time of the rolling is 10-20min;

preferably, the rolling speed is 40-50m/min.

6. Rolling process according to any one of claims 1 to 5, characterised in that the total reduction of the rolling is between 35% and 50%.

7. A rolling process according to any one of claims 1 to 6, characterized in that the rolling passes are between 2 and 6;

preferably, the reduction of a single pass of the rolling is 10% to 15%.

8. The rolling method according to claim 7, wherein a heat-retention treatment is performed after every two passes of the rolling;

preferably, the temperature of the heating and heat preservation treatment is 1150-1200 ℃;

preferably, the time of the heating and heat preservation treatment is 10-20min.

9. The rolling method according to any one of claims 1 to 8, wherein the molybdenum niobium target blank is obtained by hot isostatic pressing and capsule removal;

preferably, the molybdenum niobium target blank has a length of 1000-1500mm;

preferably, the width of the molybdenum niobium target blank is 250-400mm;

preferably, the thickness of the molybdenum niobium target blank is 100-150mm.

10. Rolling process according to any one of claims 1 to 9, characterised in that it comprises the following steps:

(1) After hot isostatic pressing, removing the sheath to obtain a first molybdenum niobium target blank;

(2) Heating the first molybdenum niobium target blank in the step (1) to 1100-1300 ℃, preserving heat for 30-60min, and cogging at a speed of 20-25m/min, wherein the total pressing amount is 40% -55%; the cogging pass is 2-4 times, the pressing amount of a single pass is 17% -22%, and after each pass, the molybdenum niobium target blank is heated to 1120-1200 ℃ and is kept for 10-15min to obtain a second molybdenum niobium target blank;

(3) Heating the second molybdenum niobium target blank in the step (2) to 1150-1250 ℃, preserving heat for 10-20min, and rolling at the speed of 40-50m/min, wherein the total pressing amount is 35% -50%; the rolling passes are 2-6 times, the pressing amount of a single pass is 10% -15%, and after every two passes, the molybdenum niobium target blank is heated to 1150-1200 ℃ and is kept warm for 10-20min, so that the molybdenum niobium target blank is obtained.