EP0641866B1 - Alloy sheet for shadow mask and method for manufacturing thereof - Google Patents

Alloy sheet for shadow mask and method for manufacturing thereof Download PDF

Info

Publication number
EP0641866B1
EP0641866B1 EP94102719A EP94102719A EP0641866B1 EP 0641866 B1 EP0641866 B1 EP 0641866B1 EP 94102719 A EP94102719 A EP 94102719A EP 94102719 A EP94102719 A EP 94102719A EP 0641866 B1 EP0641866 B1 EP 0641866B1
Authority
EP
European Patent Office
Prior art keywords
annealing
cold
less
rolling
alloy sheet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP94102719A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0641866A1 (en
Inventor
Tadashi C/O Intellectual Property Dept. Inoue
Kiyoshi C/O Intellectual Property Dept. Tsuru
Katsuhisa C/O Intellectual Pty Dept. Yamauchi
Michihito C/O Intellectual Property Dept. Hiasa
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Engineering Corp
Original Assignee
NKK Corp
Nippon Kokan Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NKK Corp, Nippon Kokan Ltd filed Critical NKK Corp
Publication of EP0641866A1 publication Critical patent/EP0641866A1/en
Application granted granted Critical
Publication of EP0641866B1 publication Critical patent/EP0641866B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
    • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
    • H01J29/06—Screens for shielding; Masks interposed in the electron stream
    • H01J29/07—Shadow masks for colour television tubes
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/08—Ferrous alloys, e.g. steel alloys containing nickel
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2229/00—Details of cathode ray tubes or electron beam tubes
    • H01J2229/07—Shadow masks
    • H01J2229/0727—Aperture plate
    • H01J2229/0733—Aperture plate characterised by the material

Definitions

  • the present invention relates to an alloy sheet for making a shadow mask used for color cathode ray tube and method for manufacturing thereof, in particular to an alloy sheet containing Fe, Ni and Cr having high press-formability and method for manufacturing thereof.
  • Recent up-grading trend of color television toward high definition TV has employed Fe-Ni alloy containing 34 to 38wt.% Ni as the alloy for making a shadow mask to suppress color-phase shift.
  • Fe-Ni alloy containing 34 to 38wt.% Ni as the alloy for making a shadow mask to suppress color-phase shift.
  • conventional Fe-Ni alloy has considerably lower thermal expansion coefficient. Accordingly, a shadow mask made of conventional Fe-Ni alloy raises no problem of color-phase shift coming from the thermal expansion of shadow mask even when an electron beam heats the shadow mask.
  • An alloy ingot is prepared by continuous casting process or ingot-making process.
  • the alloy ingot is subjected to slabbing, hot-rolling, cold-rolling, and annealing to produce an alloy sheet.
  • the alloy sheet for making a shadow mask is then processed usually in the following steps to form shadow mask.
  • the alloy sheet is photo-etched to form passage-holes for the electron beam on the alloy sheet for making a shadow mask.
  • the alloy sheet for making a shadow mask perforated by etching is hereinafter referred to as "flat mask”.
  • the flat mask is subjected to annealing.
  • the annealed flat mask is pressed into a curved shape of cathode ray tube.
  • the press-formed flat mask is assembled to a shadow mask which is then subjected to blackening treatment.
  • alloy sheet for shadow mask prepared by the process including first cold-rolling, recrystallization annealing and finish cold-rolling, which is annealed before press-forming after perforated by etching develops problems such as poor shape-fix ability, cracking on the alloy sheet and blurred periphery of the pierced hole during press-forming, which is a significant disadvantage of manufacturing a cathode ray tube.
  • the prior art was proposed in JP-A-3-267320 (the term JP-A- referred to herein signifies unexamined Japanese patent publication), where a method to decrease the strength of the conventional Fe-Ni alloy and solve the problems is provided.
  • said art is referred to as prior art 1.
  • the prior art 1 employs first cold-rolling, recrystallization annealing, finish cold-rolling and softening annealing.
  • the finish cold-rolling is performed at a reduction ratio of 5 to 20%, and the temperature of the softening annealing is less than 800°C.
  • the prior art 1 produces a sheet having sufficiently low strength to give good press-formability with the 0.2% proof stress of 9.5 kgf/mm 2 (10 kgf/mm 2 or less) at 200°C.
  • the prior art 2 was proposed in JP-B-64-52024, where a method to reduce a plane anisotropy as mechanical property is provided.
  • the prior art 2 employs the process including cold-rolling followed by recrystallization annealing repeated twice or more, and cold-rolling to increase hardness.
  • finish cold-rolling before finish recrystallization annealing is performed at the reduction ratio of 40 to 80%.
  • the plate for shadow mask has excellent uniform formability during press-forming resulting in a small deformation of etched-hole and free form the irregular gloss and stringer defect when the plate is etched, annealed and press-formed.
  • the prior art 1 does not satisfy the quality required to perform a favorable warm press-forming, though the strength is lowered to the level suitable for press-forming under the above described annealing condition.
  • the alloy sheet for shadow mask prepared by the prior art was found to gall a die and to generate cracks at the edge of shadow masks.
  • the above described alloy sheet for making a shadow mask often develops a quality problem of blurred periphery of pierced hole after press-forming, as the plane anisotropy of the alloy is large.
  • EP-A-0 552 800 discloses an alloy sheet for a shadow mask in which the degrees of the planes ⁇ 211 ⁇ , ⁇ 210 ⁇ and ⁇ 331 ⁇ are controlled. Not disclosed is the degree of mixed grain for austenite grains or the average austenite grain size.
  • the object of the present invention is to provide an alloy sheet for making a shadow mask having excellent corrosion resistance and high press-formability, which developes no crack nor blurred periphery of pierced hole during press-forming and does not generate a color phase shift when used for cathode ray tubes and method for manufacturing thereof.
  • the present invention provides an alloy sheet as defined in claims 1 and 4. Preferred embodiments are given in the dependent claims.
  • the present invention also provides a method for manufacturing an alloy sheet defined in claims 9 and 13. Preferred embodiments are given in the dependent claims.
  • the inventors made extensive study to develop a Fe-Ni alloy sheet and Fe-Ni-Cr alloy sheet for shadow mask having high press-formability and suppressing partial color phase shift and found that the desired press-formability is obtained while suppressing the above mentioned color phase shift by adjusting the chemical composition, austenite grain size, degree of mixed grains for austenite grains, and crystal orientation of the Fe-Ni alloy sheet for making a shadow mask within a specified range.
  • Presence of B and O within a specified range enhances growth of crystal grains during the annealing before press-forming.
  • the growth of crystal grains yields the austenite grain having specified size, which gives shape fix ability during press-forming.
  • the presence of Si and N within a specified range supresses the galling of dies and improves the fitness to die during press-forming.
  • the control of gathering degree of ⁇ 211 ⁇ plane on the alloy sheet after annealing before press-forming within a specified range suppresses the generation of crack on material during press-forming.
  • the hot-rolled strip is subjected to hot-rolled sheet annealing at a specific temperature before cold-rolling.
  • Both cold-rolling and finish cold-rolling control their reduction ratio, and the annealing before press-forming controls the condition within each specified range.
  • the average austenite grain size and gathering degree of ⁇ 331 ⁇ , ⁇ 210 ⁇ and ⁇ 211 ⁇ plane on the surface of alloy sheet are adjusted within specified range.
  • once or twice of cold-rolling after the annealing of hot-rolled sheet are conducted under a reduction ratio within a specified range.
  • This invention has been derived based on the findings described above.
  • the reason of specifying the chemical composition, austenite grain size and degree of mixed grain for austenite grains after annealing before press-forming, and the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane of the Fe-Ni alloy sheet and Fe-Ni-Co-Cr alloy sheet surface for making shadow mask of the present invention within the range above described is clarified in the following.
  • the Fe-Ni alloy sheet for making a shadow mask is necessary to have the upper limit of average thermal expansion coefficient as approximately 2.0 x 10 -6 /°C in the temperature range of 30 to 100°C.
  • the thermal expansion coefficient depends on the content of Ni in the alloy sheet.
  • the Ni content which satisfies the above limitation of average thermal expansion coefficient is 34 to 38 wt.%. Consequently, the Ni content should be limited to 34 to 38wt.%. More preferably, the Ni content to decrease average thermal expansion coefficient is 35 to 37 wt.%, and most preferably 35.5 to 36.5 wt.%.
  • Ni content to satisfy the upper limit of the average thermal expansion coefficient is 34 to 38 wt.%, and most preferably in a range of 35 to 38 wt.%.
  • the alloy includes over 1.0 to 7wt.% Co the range of Ni content to satisfy the above described condition of average thermal expansion coefficient is 27 to 38 wt.%, and the average thermal expansion coefficients of Fe-Ni-Co-Cr alloy and Fe-Ni-Cr aloy are further reduced by limiting Ni content to 30 to 33 wt.% and Co to 3 to 6 wt.%.
  • Chromium improves the corrosion resistance of alloy, but increases thermal expansion coefficient. Chromium content of less than 0.05% gives no effect of improvement in corrosion resistance. On the other hand, when the Cr content exceeds 3wt.%, the alloy can not provide the average thermal expansion coefficient specified by the present invention. Therefore, the lower limit and the upper limit of Cr content are specified as 0.05 wt.% and 3.0 wt.%, respectively.
  • the average austenite grain size which is requested from the reason of improving shape fix ability, suppressing the generation of crack on alloy sheet during press-forming and of preventing the blurred periphery of pierced hole after press-forming is 15 to 45 ⁇ m for warm press-forming. Grain size of less than 15 ⁇ m gives poor shape fix ability and generates cracks on alloy sheet. Grain size above 45 ⁇ m, however, generates cracks and blurred periphery of pierced hole after press-forming. Consequently, the average austenite grain size is specified as 15 to 45 ⁇ m.
  • the control of gathering degree of ⁇ 211 ⁇ plane on alloy sheet within a specified range while maintaining the above described average austenite grain size is essential as described later.
  • the control of O and B content of specified level or less is necessary.
  • the control of Si and N content of specified level or less is necessary. The following is the description of the content of such elements.
  • Oxygen is one of the inevitable impurities. Increased content of O increases the non-metallic oxide inclusion within the alloy, which inclusion suppresses the growth of crystal grains during the annealing before press-forming, particularly in the temperature range of 740 to 900°C for 40min. or less. If the content of O exceeds 0.0030 wt.%, then the growth of crystal grains described above is considerably suppressed, and no austenite grain size aimed in this invention is obtained. Consequently, the upper limit of O content is specified to 0.0030% and the lower limit is specified to 0.0001%.
  • Boron also increases the gathering degree of ⁇ 211 ⁇ plane after annealing, which causes the crack on a skirt of material. Boron content above 0.0030 wt.% significantly enhances the suppression of grain growth, and the austenite grain size aimed in the present invention can not be obtained. Also the blurred periphery of pierced hole during press-forming occurs, and the gathering degree of ⁇ 211 ⁇ plane exceeds the upper limit specified in the present invention. Based on these findings, the upper limit of B content is defined as 0.0030 wt.%.
  • Silicon is used as the deoxidizer during ingot-making of the alloy.
  • Si content exceeds 0.10 wt.%, an oxide film of Si is formed on the surface of alloy during the annealing before press-forming.
  • the oxide film degrades the fitness to dies during press-forming and results in the galling of dies with alloy sheet. Consequently, the upper limit of Si content is specified as 0.10 wt.%. Less Si content further improves the fitness of dies and alloy sheet.
  • the lower limit is specified to 0.001%.
  • Nitrogen is an element unavoidably entering into the alloy during ingot-making process. Nitrogen content of more than 0.0030 wt.% induces the concentration of N on the surface of alloy during the annealing before press-forming. The concentrated N on the surface of alloy degrades the fitness to dies during press-forming and induces galling of dies with the alloy sheet. Consequently, the upper limit of N content is specified as 0.0030 wt.% and the lower limit is specified to 0.0001%.
  • An alloy for shadow mask of the present invention contains specific amount of O, B, Si, and N in its Fe-Ni-Cr and Fe-Ni-Co-Cr basic composition, and has an average austenite grain size of 15 to 45 ⁇ m after annealing before press-forming, and has degree of mixed grain for austenite grains of 50% or less, and has 20% or less, 35% or less, 20% or less of the gathering degree of ⁇ 211 ⁇ , ⁇ 331 ⁇ , ⁇ 210 ⁇ plane, respectively. Most preferably, the composition further contains 0.0001 to 0.0040 wt.% C, 0.001 to 0.35 wt.% Mn, and 2.0 ppm or less H.
  • control of chemical composition and of average austenite grain size after annealing before press-forming within the range specified in the present invention suppresses the galling of dies with alloy during press-forming and gives a superior shape fix ability.
  • the inventors studied the relation between the crack generation and the crystal grain orientation during press-forming by changing the crystal grain orientation of the alloy sheet in various directions using the alloy sheets having chemical composition and average austenite grain size in the range specified in the present invention, and found that an effective condition to suppress the crack generation on the alloy material is to control the gathering degree of ⁇ 211 ⁇ plane at or less than a specific value, as well as to control the average austenite grain size after the annealing before press-forming at or less than a specific level.
  • Fig. 1 shows the relation among crack generation on alloy sheet during press-forming, gathering degree of ⁇ 211 ⁇ plane, and average austenite grain size for alloy sheet having chemical composition specified in the present invention.
  • the gathering degree of ⁇ 211 ⁇ plane is determined from the relative X-ray diffraction intensity ratio of (422) diffraction plane of alloy sheet after the annealing before press-forming divided by the sum of relative X-ray diffraction intensity ratio of (111), (200), (220), (311), (331), (420), and (422) diffraction planes.
  • the measurement of gathering degree of ⁇ 211 ⁇ plane was carried by measuring the diffraction of ⁇ 422 ⁇ plane which has equivalent orientation with ⁇ 211 ⁇ plane.
  • the relative X-ray diffraction intensity ratio is defined as the value of X-ray diffraction intensity observed on each diffraction plane divided by the theoretical X-ray diffraction intensity of that diffraction plane.
  • the relative X-ray diffraction intensity ratio of (111) diffraction plane is determined from the X-ray diffraction intensity of (111) diffraction plane divided by the theoretical X-ray diffraction intensity of (111) diffraction plane.
  • the measurement of the gathering degree of ⁇ 331 ⁇ and ⁇ 210 ⁇ plane was carried by measuring the relative X-ray diffraction intensity ratio of (331) diffraction plane and (420) diffraction plane (which have the equivalent factor with ⁇ 211 ⁇ plane) divided by the sum of relative X-ray intensity ratio of seven diffraction planes from (111) to (422) described above, respectively.
  • Fig. 1 clearly shows that the case where average austenite grain size is 15 to 45 ⁇ m and where the gathering degree of ⁇ 211 ⁇ plane is 20% or less does not generate crack on alloy sheet during press-forming and does not induce blurred periphery of the pierced hole, which fact indicates the excellent effect of the present invention.
  • the invention specifies the gathering degree of ⁇ 211 ⁇ plane as 20% or less as the condition to suppress crack generation on the alloy sheet.
  • Fig. 2 shows the relation between the frequency of blurred periphery of the pierced hole and degree of mixed grain for austenite grains after press-forming using an alloy sheet having chemical composition, average austenite grain size and the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane within the range specified in the present invention.
  • the figure indicates that the degree of mixed grain for austenite grains more than 50% increases the frequency of blurred periphery of pierced hole. Consequently, the degree of mixed grain for austenite grains to suppress generation of blurred periphery of the pierced hole after press-forming is specified as 50% or less.
  • the control of gathering degrees of ⁇ 331 ⁇ plane and ⁇ 210 ⁇ plane after annealing before press-forming is important, which is described before.
  • the gathering degrees of ⁇ 331 ⁇ and ⁇ 210 ⁇ plane exceeds 35% and 20% after annealing before press-forming, respectively, partial color-phase shift will occur. Consequently, this invention specifies the degrees of ⁇ 331 ⁇ plane and ⁇ 210 ⁇ plane as 35% or less and 20% or less, respectively.
  • the method to keep the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane after annealing before press-forming at or less than 35%, 16%, and 20% is to adopt the alloy sheet manufacturing condition which prevent aggregation of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane during the steps of solidification, hot-rolling, cold-rolling, and annealing of this alloy sheet as far as possible.
  • the hot-rolled strip is subjected to annealing of hot-rolled sheet, cold-rolling, recrystallization annealing, finish cold-rolling, stress relief annealing, annealing before press-forming, press-forming, and blackening.
  • adequate annealing of hot-rolled sheet after hot-rolling is effective to prevent gathering of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane.
  • the gathering degree of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane can be kept at or less than the level specified in this invention.
  • the present invention specifies the annealing temperature of hot-rolled sheet as 810 to 890°C which provides the gathering degree of ⁇ 331 ⁇ plane of 35% or less, degree of ⁇ 210 ⁇ plane of 20% or less, and degree of ⁇ 211 ⁇ plane of 20% or less.
  • the effect of annealing of hot-rolled sheet in the present invention is performed when the hot-rolled alloy strip is fully recrystallized before the annealing of hot-rolled sheet.
  • the uniform heat treatment of the slab after slabbing is not preferable. For example, when a uniform heat treatment is carried at a temperature of 1200°C or more for a period of 10 hours or more, at least one of the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane exceeds the range specified in the present invention. Therefore, such a uniform heat treatment must be avoided.
  • the optimization of all conditions in the cold-rolling, annealing, finish cold-rolling, stress-relief annealing, and annealing before press-forming are required to assure the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane and the degree of mixed grain for austenite grains to be in the range specified in this invention.
  • the optimization of conditions of cold-rolling and annealing is important to control the gathering degree of mixed grain for austenite grains after annealing before press-forming.
  • Fig. 3 shows the relation between the reduction ratio of cold-rolling and the degree of mixed grain for austenite grains after annealing before press-forming.
  • this is the graph showing the relation between the degree of mixed grain for austenite grains and the reduction ratio of first cold-rolling of the alloy sheet prepared from hot-rolled strip which was subjected to the process including the annealing of hot-rolled sheet in the temperature range of 810 to 890°C, first cold-rolling at the reduction ratio of 73 to 97%, recrystallization, finish cold-rolling at the reduction ratio of 14 to 29%, and stress-relief annealing in the temperature range of 450 to 540°C for 0.5 to 300 sec., followed by the annealing in the temperature range of 740 to 900°C for 2 to 40min. before press-forming.
  • Fig. 3 indicates that the reduction ratio of cold-rolling of 81 to 94% gives the degree of mixed grain for austenite grains of 50% or less when the process of intermediate cold-rolling and annealing are conducted only once. On the other hand, the reduction ratio of cold-rolling of less than 81% or more than 94% gives the degree of mixed grain for austenite grains of more than 50%.
  • the present invention specifies the reduction ratio of cold-rolling as 81 to 94% to secure the degree of mixed grain for austenite grains at or below 50% for single cycle of cold-rolling and annealing.
  • Fig. 4 is a graph showing a relation between the reduction ratio of cold-rolling and a degree of mixed grain for austenite grains when the process of intermediate cold-rolling and annealing is performed twice.
  • this is the graph showing the relation between the degree of mixed grain for austenite grains and the reduction ratios of first cold-rolling and second cold-rolling of the alloy sheet prepared from hot-rolled strip which was subjected to the process including the annealing of hot-rolled sheet in the temperature range of 810 to 890°C, first cold-rolling at the reduction ratio of 35 to 60%, recrystallization annealing, second cold-rolling at the reduction ratio of 75 to 97%, recrystallization annealing, finish cold-rolling at the reduction ratio of 14 to 29%, and stress relief annealing in the temperature range of 450 to 540°C for 0.5 to 300 sec., followed by annealing in the temperature range of 740 to 900°C for 2 to 40 min. which annealing time (T) satisfying
  • the degree of mixed grain for austenite grains gives satisfactory value when the reduction ratio of second cold-rolling is 81 to 94 % and the reduction ratio of first cold-rolling is 40 to 55%.
  • the present invention specifies the reduction ratio of first cold-rolling as 40 to 55% and that of second cold-rolling as 81 to 94% for the case of two cycles of cold-rolling and annealing.
  • the recrystallization annealing after first and second cold-rolling is preferably carried at 810 to 840°C for 0.5 to 3min. Even when the annealing temperature exceeds the recrystallization temperature, the annealing at the temperature of 810°C or less induces the formation of mixed grains, and the degree of mixed grain for austenite grains increases after the annealing before press-forming.
  • the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane becomes 35% or less, 20% or less, and 20% or less, respectively.
  • the resulted characteristics are: 15 - 45 ⁇ m of average austenite grain size; 50% or less of degree of mixed grain for austenite grains; 35% or less of gathering degree of ⁇ 331 ⁇ plane; 20% or less of gathering degree of ⁇ 210 ⁇ plane; and 20% or less of gathering degree of ⁇ 211 ⁇ plane, after the annealing before press-forming.
  • the reduction ratio of finish cold-rolling is less than 14% or more than 29%, at least one of the above described characteristics which are the feature of the present invention becomes out of the scope of the present invention. Consequently, the reduction ratio of finish cold-rolling is specified as 14 to 29%.
  • the optimization of the condition of annealing before press-forming is also important to obtain the value of average austenite grain size, degree of mixed grain for austenite grains.
  • Fig. 5 shows the relation among average austenite grain size, degree of mixed grain for austenite grains, gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane after annealing before press-forming, and temperature (T, °C) and time (t , min.) of annealing before press-forming under the conditions of hot-rolled sheet annealing, cold-rolling and annealing, and the reduction ratio of finish cold-rolling within the range specified in the present invention.
  • the condition to obtain satisfactory values of average austenite grain size, degree of mixed grain for austenite grains, and gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane is specified in the present invention as T : 740 to 900°C, t : 2 to 40 min., and T ⁇ -123 log t + 937.
  • the stress relief annealing in the present invention is important to control the gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane in the succeeding annealing before press-forming.
  • the stress relief annealing should be conducted at 450 to 540°C for 0.5 to 300 sec. to demonstrate the enough effect aimed in the present invention.
  • annealing before press-forming in the present invention may be applied before photo-etching. In that case, desired photo-etching quality is ensured only when the condition of annealing before press-forming is kept within the range specified in this invention.
  • the continuous cast slabs were subjected to scarfing, then heated at 1100°C for 3 hrs in a heating furnace and hot-rolled to obtain hot-rolled strips.
  • the hot-rolled strips were subjected to a process including annealing of hot-rolled sheet at 860°C, first cold-rolling at the reduction ratio of 93%, recrystallization annealing at 810°C for 1 min.
  • the process further includes finish cold-rolling at the reduction ratio of 21%, stress-relief annealing at 530°C for 1 min. to obtain alloy sheets having 0.25mm thickness.
  • the alloy sheets obtained by the above described method were put to various experiments described below.
  • the materials of No. 1 to No. 21 correspond to the alloys of No. 1 to No. 21. Said hot-rolled strips which were fully recrystallized after hot-rolling were selected.
  • the alloy sheets of materials No. 1 through No. 3, No. 5 through No. 21 were formed into flat masks by etching and then they were subjected to annealing before press-forming under the condition specified in Table 2 and to press-forming.
  • the press-formed sheets were tested to determine the shape fix ability, fitness to dies, crack generation on material, and frequency of blurred periphery of pierced hole based on the evaluation criteria given in Table 4.
  • the materials were investigated for the corrosion resistance after stress relief annealing based on the evaluation criteria given in Table 4. Table 2 Material No.
  • the flat masks after etching described above were found to have no blurred perifery of pierced hole and have sufficient etching performance.
  • Their average austenite grain size, degree of mixed grain for austenite grains, tensile properties (n value, r value, and elongation) and gathering degree of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane were determined after annealing before press-forming.
  • the gathering degree of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane was determined by X-ray diffraction method which was described before. The result is shown in Table 3.
  • the alloy sheet of material No. 4 was subjected to stress relief annealing under the condition described above, annealing before press-forming under the condition given in Table 2, and to etching to form a flat mask followed by press-forming.
  • the characteristics of the material were determined by the same methods applied to other materials. Partial color-phase shift was determined after blackening the press-formed shadow mask, assembling the mask into the cathode ray tube, and irradiating electron beam onto the cathode ray tube for a specified period.
  • Table 4 shows the result of experiments of press-formablity (shape-fix ability, fitness to die, crack generation on alloy sheet, blurred periphery of pierced hole), partial color-phase shift and corrosion resistance (generation of spot rust; number/100 cm 2 ).
  • press-formablity shape-fix ability, fitness to die, crack generation on alloy sheet, blurred periphery of pierced hole
  • partial color-phase shift and corrosion resistance generation of spot rust; number/100 cm 2 .
  • materials No. 1 through No. 13 and material No. 13-1 having chemical composition, gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane, average austenite grain size, and degree of mixed grain for austenite grains within the range specified in the present invention, show high press-formability without inducing partial color-phase shift and have corrosion resistance better than material No. 16 described later.
  • Material No. 4 was etched after annealing before press-forming, and the flat mask prepared from the material induced no blurred periphery of pierced hole and showed satisfactory etching performance.
  • Material No. 13-1 which includes more Co than other materials showed characterlistics as excellent as others.
  • material No. 14 gives Si content of 0.12 wt.% and material No. 16 gives N content of 0.0035 wt.%, which are more than the upper limit of the present invention, and raises problem of fitness to dies.
  • Material No. 15 gives O content of 0.0035 wt.%, which is more than the upper limit of the present invention and also gives average austenite grain size (referred to simply as “average grain size” hereafter) of 13 ⁇ m, which is less than the lower limit of this invention, results in a poor shape fix ability, induces crack generation on alloy sheet, gives degree of mixed grain for austenite grains (referred to simply as "degree of mixed grain” hereafter) above the upper limit of the present invention and results in blurred periphery of pierced hole to raise problem of press-formability.
  • Cr is not added to material No. 16, which shows cosrrosion resistance much inferior to those of the examples of the present invention.
  • Material No. 17 and No. 18 give B content of 0.0035 wt.% and 0.0033 wt.%, respectively, which are more than the upper limit of the present invention and give average grain sizes of 12 ⁇ m and 14 ⁇ m, respectively, which are less than the lower limit of the present invention, 15 ⁇ m, resulting in poor shape fix ability. Also degrees of mixed grain of material No. 17 and No. 18 are 56% and 63%, respectively, which are more than the upper limit of the present invention, inducing blurred periphery of the pierced hole. The gathering degrees of ⁇ 211 ⁇ plane of the materials are 30% and 34%, which are more than the upper limit of the present invention, 20%, inducing cracks on the alloy sheet, and raise problems of press-formability.
  • materials No. 19 show the degree of mixed grain of 21%, which are more than the upper limit of the present invention, 20%.
  • Material No. 20 show the gathering degree of ⁇ 331 ⁇ plane of 38%, which are more than the upper limit of the present invention, 38%. Both materials give partial color phase shift, causing quality problems of screen.
  • Material No. 21 shows average grain size of 52 ⁇ m, which is more than the upper limit of the present invention, 45 ⁇ m, to generate crack on the alloy sheet and induces blurred periphery of the pierced hole, which results in press-formability problem.
  • Material No. 19 show the degree of mixed grain of 21%, which are more than the upper limit of the present invention, 20%.
  • Material No. 20 show the gathering degree of ⁇ 331 ⁇ plane of 38%, which are more than the upper limit of the present invention, 38%. Both materials give partial color phase shift, causing quality problems of screen.
  • Material No. 21 shows average grain size of 52 ⁇ m, which is more than the upper limit of the present invention,
  • Fe-Ni-Cr alloy sheet and Fe-Ni-Co-Cr alloy sheet for shadow mask having high press-forming quality, screen quality and corrosion resistance are prepared by adjusting the chemical composition, gathering degrees of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane, average grain size, and degree of mixed grain within the range specified in the present invention.
  • the hot-rolled strips of alloys No. 1 through No. 13 and No. 13-1 which were used in Example 1 were subjected to annealing of hot-rolled sheet under the temperature condition given in Table 5, cold-rolling at the reduction ratio in Table 5 (if the column of CR 1 is blank, it indicates that single cold-rolling was carried applying the reduction ratio given in CR 2 ; if both columns of CR 1 and CR 2 are filled, it indicate that two cold-rollings were carried applying the reduction ratio given in each column).
  • the materials were treated by recrystallization annealing at 810°C for 1min., finish cold-rolling at the reduction ratio of cold-rolling given in Table 5, stress relief annealing at 530°C for 0.5sec., to obtain alloy sheets of materials No. 22 through No. 47 each having 0.25mm of thickness.
  • the alloy sheets of materials No. 40 and No. 43 were subjected to stress relief annealing under the condition described above and to annealing before press-forming under the condition given in Table 5 and to etching, then they were formed to flat masks and were press-formed. The characteristics of these materials were determined by the same method applied to other materials.
  • materials No. 31 through No. 47 have chemical composition within the range specified in the present invention and have the conditions of annealing of hot-rolled sheet, reduction ratio of first and second cold-rolling, finish cold-rolling, annealing before press-forming (temperature: T, °C, time: t, min.), gathering degree of ⁇ 331 ⁇ , ⁇ 210 ⁇ , and ⁇ 211 ⁇ plane, average grain size, and degree of mixed grain within the range specified in the present invention. So the materials No. 31 through No. 47 show high press-formability without inducing partial color-phase shift. Materials No. 40 and No. 43 were etched after the annealing before press-forming. The flat masks prepared from the materials No. 40 and No. 43 showed no blurred periphery of the piercedhole and gave sufficient etching performance.
  • Material No. 47 including Co also shows the excellent characteristics.
  • materials No. 32, No. 35 through No. 37, No. 39, No. 43 through No. 45 and No. 47 were treated by two cold-rollings where the reduction ratio of first cold-rolling, CR 1 , was 40 to 55%, and they gave less (more preferable) degree of mixed grain than that of the materials of single cold-rolling (materials No. 31, No. 33, No. 34, No. 38, No. 40 through No. 42, No. 46).
  • materials No. 22 was subjected to annealing of hot-rolled sheet at 800°C, which is less than the lower limit of the present invention, 810°C
  • material No. 23 was subjected to annealing of hot-rolled sheet at 900°C, which is more than the upper limit of the present invention. Both materials have the gathering degrees of ⁇ 210 ⁇ and ⁇ 211 ⁇ plane more than the upper limit of the present invention.
  • Material No. 22 gives partial color-phase shift which causes a problem of screen quality
  • Material 23 gives cracking on the alloy sheet which gives a problem of press-formability.
  • Material No. 24 is subjected to one cold-rolling at the reduction ratio of 95%, which is more than the upper limit of the present invention, 94%, and material No. 25 was subjected to one cold-rolling at the reduction ratio of 80%, which is less than the lower limit of the present invention, 81%. Both materials give degrees of mixed grain of 59% and 55%, respectively, which are more than the upper limit of the present invention, that induce blurred periphery of the pierced hole to raise problem of press-formability.
  • Material No. 26 was subjected to the one cold-rolling at the reduction ratio of 40%, which is more than the upper limit of the present invention, 29%, and material No. 27 was subjected to the one cold-rolling at the reduction ratio of 12%, which is less than the lower limit of the present invention, 14%.
  • Material No. 26 gives average grain size of 13 ⁇ m, which is less than the lower limit of the present invention, 15 ⁇ m, inducing a problem of the shape fix ability to generate cracking on the alloy sheet.
  • Material No. 27 gives a degree of mixed grain of 60%, which is more than the upper limit of the present invention, 50%, inducing blurred periphery of pierced hole.
  • Maerial No. 28 was subjected to the annealing before press-forming at 920°C, which is more than the upper limit of the present invention, 900°C
  • material No. 29 was subjected to the annealing before press-forming for 50 min., which is more than the upper limit of the present invention, 40 min., and as for material No. 30, annealing temperature (T) does not satisfy the equation of(T ⁇ - 123logt + 937) .
  • Material No. 28 gives average grain size of 48 ⁇ m, which is more than the upper limit of the present invention, 45 ⁇ m, inducing a problem of blurred periphery of the pierced hole.
  • Material No. 28 also gives the gathering degree of ⁇ 211 ⁇ plane of 25%, which is more than the upper limit of the present invention, 20%, inducing cracking on the alloy sheet.
  • Material No. 29 gives the gathering degree of ⁇ 331 ⁇ plane of 38%, which is more than the upper limit of the present invention, 35%, inducing cracking on the alloy sheet and partial color phase shift.
  • Material No. 30 gives average grain size of 13 ⁇ m, which is less than the lower limit of the present invention, 15 ⁇ mm, inducing a problem of shape fix ability. Material No. 30 also gives the gathering degree of ⁇ 211 ⁇ plane of 26%, which is more than the upper limit of the present invention, 20%, inducing cracking on the alloy sheet.
  • control of the conditions of annealing of hot-rolled sheet, cold-rolling, reduction ratio of finish cold-rolling, and annealing before press-forming within the range specified in the present invention is as important as the chemical composition to be in the range specified in the present invention to provide the press-formability and screen quality intended by the present invention.
  • the flat masks obtained from Fe-Ni-Cr and Fe-Ni-Co-Cr alloy sheets having press-formability required by the present invention without generating partial color-phase shift show no blurred periphery of the pierced hole and give sufficient etching performance.
  • Example 1 and Example 2 the case that the gathering degree of ⁇ 211 ⁇ plane exceeds 20% and/or that average grain size is outside the scope of this invention provides low value of elongation, n value, and r value after annealing before press-forming compared with the preferred embodiment of the present invention.
  • these values are presumably decreased inducing crack generation during press-forming.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Sheet Steel (AREA)
  • Heat Treatment Of Steel (AREA)
  • Electrodes For Cathode-Ray Tubes (AREA)
EP94102719A 1993-08-27 1994-02-23 Alloy sheet for shadow mask and method for manufacturing thereof Expired - Lifetime EP0641866B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP213001/93 1993-08-27
JP5213001A JP2871414B2 (ja) 1993-08-27 1993-08-27 プレス成形性に優れたシャドウマスク用合金薄板およびその製造方法

Publications (2)

Publication Number Publication Date
EP0641866A1 EP0641866A1 (en) 1995-03-08
EP0641866B1 true EP0641866B1 (en) 1997-07-23

Family

ID=16631845

Family Applications (1)

Application Number Title Priority Date Filing Date
EP94102719A Expired - Lifetime EP0641866B1 (en) 1993-08-27 1994-02-23 Alloy sheet for shadow mask and method for manufacturing thereof

Country Status (5)

Country Link
EP (1) EP0641866B1 (zh)
JP (1) JP2871414B2 (zh)
KR (1) KR970003642B1 (zh)
CN (1) CN1039544C (zh)
DE (1) DE69404403T2 (zh)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000017394A (ja) * 1998-04-30 2000-01-18 Dainippon Printing Co Ltd カラ―ブラウン管用シャドウマスク
DE19821299A1 (de) * 1998-05-13 1999-11-18 Abb Patent Gmbh Anordnung und Verfahren zum Erzeugen von Warmband
FR2811684B1 (fr) * 2000-07-13 2002-08-30 Imphy Ugine Precision Bande en alliage fe-ni ou fe-ni-co ou fe-ni-co-cu a decoupabilite amelioree
JP2002038239A (ja) * 2000-07-24 2002-02-06 Yamaha Metanikusu Kk 磁気歪制御型合金板及びこれを用いたカラーブラウン管用部品並びに磁気歪制御型合金板の製造方法
JP6186043B1 (ja) * 2016-05-31 2017-08-23 日本冶金工業株式会社 Ｆｅ−Ｎｉ−Ｃｒ合金、Ｆｅ−Ｎｉ−Ｃｒ合金帯、シーズヒーター、Ｆｅ−Ｎｉ−Ｃｒ合金の製造方法及びシーズヒーターの製造方法
CN112322993A (zh) * 2020-11-19 2021-02-05 苏州钿汇金属材料有限公司 一种超薄铁镍合金材料及其制造方法
CN113215494B (zh) * 2021-05-07 2022-01-28 西安钢研功能材料股份有限公司 一种航空用因瓦合金板材的制备方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61113747A (ja) * 1984-11-07 1986-05-31 Nippon Mining Co Ltd シヤドウマスク材
JPS61113746A (ja) * 1984-11-07 1986-05-31 Nippon Mining Co Ltd シヤドウマスク材
DE3636815A1 (de) * 1985-11-12 1987-05-14 Nippon Mining Co Schattenmaske und verfahren zur herstellung von schattenmasken
JPS63259054A (ja) * 1987-04-16 1988-10-26 Nippon Mining Co Ltd シヤドウマスク
JPH03197645A (ja) * 1989-12-26 1991-08-29 Nippon Mining Co Ltd リードフレーム材
JPH0610323B2 (ja) * 1990-04-21 1994-02-09 東洋鋼鈑株式会社 低熱膨張型シャドウマスク用素材およびその製造法
EP0561120B1 (en) * 1992-01-24 1996-06-12 Nkk Corporation Thin Fe-Ni alloy sheet for shadow mask and method for manufacturing thereof
US5308723A (en) * 1992-01-24 1994-05-03 Nkk Corporation Thin metallic sheet for shadow mask

Also Published As

Publication number Publication date
KR970003642B1 (ko) 1997-03-20
JP2871414B2 (ja) 1999-03-17
DE69404403T2 (de) 1997-12-18
CN1099431A (zh) 1995-03-01
CN1039544C (zh) 1998-08-19
KR950006012A (ko) 1995-03-20
EP0641866A1 (en) 1995-03-08
DE69404403D1 (de) 1997-08-28
JPH0762496A (ja) 1995-03-07

Similar Documents

Publication Publication Date Title
EP0561120B1 (en) Thin Fe-Ni alloy sheet for shadow mask and method for manufacturing thereof
JP2596210B2 (ja) 焼鈍時の密着焼付き防止法、ガス放散性に優れたシャドウマスク用Ｆｅ―Ｎｉ合金およびその製造法
US4724012A (en) Material for in-tube components and method of manufacturing it
EP0552800B1 (en) Thin metallic sheet for shadow mask
EP0641866B1 (en) Alloy sheet for shadow mask and method for manufacturing thereof
EP0627494B1 (en) Alloy sheet for shadow mask and method for manufacturing thereof
US5522953A (en) Method of manufacturing an alloy sheet
US5562783A (en) Alloy sheet for shadow mask
EP0626461B1 (en) Iron-nickel alloy sheet for shadow mask
JP2567159B2 (ja) 黒化処理性に優れたＦｅ−Ｎｉ系シャドウマスク材
US5637161A (en) Method of producing an alloy sheet for a shadow mask
JP2870399B2 (ja) 加工性に優れたカラー受像管用Ｆｅ−Ｎｉ系合金薄板およびＦｅ−Ｎｉ−Ｃｏ系合金薄板
US20020117241A1 (en) Method of manufacturing Fe-Ni alloy material for pressed flat mask
US5456771A (en) Thin Fe-Ni alloy sheet for shadow mask
US20040238076A1 (en) Fe-ni based alloy for shadow mask raw material excellent in corrosion resistance and shadow mask material
US6600259B1 (en) Fe-Ni alloy with excellent magnetic properties for semi-tension mask, semi-tension mask of the alloy, and color picture tube using the mask
JP3353321B2 (ja) プレス成形性に優れたシャドウマスク用Ｆｅ−Ｎｉ合金薄板の製造方法及びプレス成形性に優れたシャドウマスク用Ｆｅ−Ｎｉ合金薄板
JPH0657384A (ja) プレス成形性に優れたシャドウマスク用Ｆｅ−Ｎｉ合金薄板およびＦｅ−Ｎｉ−Ｃｏ合金薄板およびその製造方法
JP2970316B2 (ja) 黒化処理性に優れたシャドウマスク用Ｆｅ−Ｎｉ系合金薄板およびＦｅ−Ｎｉ−Ｃｏ系合金薄板
JP3042273B2 (ja) 耐銹性に優れたＩＣリードフレーム用Ｆｅ−Ｎｉ 系合金薄板の製造方法
JP3326897B2 (ja) シャドウマスク用Ｆｅ−Ｎｉ系合金薄板
JP3079897B2 (ja) プレス成形性に優れたカラー受像管用Ｆｅ−Ｎｉ系合金薄板およびＦｅ−Ｎｉ−Ｃｏ系合金薄板とその製造方法
JPH09137220A (ja) 電子部材用Ｆｅ−Ｎｉ系合金薄板およびその製造方法
JP2909299B2 (ja) 高精細シャドウマスク用材料、同マスク材料およびその製造方法
JPH07243004A (ja) 磁気特性に優れたカラー受像管用Ｆｅ−Ｎｉ系合金薄板 およびＦｅ−Ｎｉ−Ｃｏ系合金薄板およびその製造方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19940223

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 19950814

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REF Corresponds to:

Ref document number: 69404403

Country of ref document: DE

Date of ref document: 19970828

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19990225

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19990301

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20000223

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20000223

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20001201

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20070208

Year of fee payment: 14

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20081031

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20080229