Be used to make the Fe-Ni alloy and the punched electron gun parts thereof of electron gun parts
The present invention relates to be suitable for and make electron gun parts (as electron gun electrodes) material, the iron-nickel alloy that its punching performance is good.The present invention also relates to punch out the blank of this alloy, on blank, go out then and be used for the punched electron gun parts that the aperture by electron beam makes, be generally electron gun electrodes.
Fig. 1 is the viewgraph of cross-section of shadow mask type colour tube known in the art.The back side of display screen 1 scribbles can send red, green, blue trichromatic fluorescent screen 2.At neck an electron beam gun 4 that can send electron beam 3 is housed.Electron beam 3 is deflected 5 deflections of coil during scanning.Mark 6 expression shadow masks, mark 7 expression magnetic fields.
Fig. 2 (a) and (b) be respectively the skeleton view and the cross-sectional view of electrode 10 (being assemblied in an example of the punch components in the electron beam gun 4).Electrode 10 is used for quickening the electronics that sends from gun cathode.This electrode has aperture 10a, 10b and the 10c that makes with impression and punching, and these apertures allow generation electron beam red, green and blue look pass through respectively.
The electron gun parts that is used for chromoscope etc. is generally made by the non-magnetic stainless steel plate that die-cut, punching press and impression (or not having impression) thickness are about the 0.05-0.5 millimeter.
As everyone knows, non-magnetic stainless steel is a material commonly used in the electron gun of colour display tube etc.With regard to the electrode 10 of the electronics that is used for quickening sending from gun cathode, people wish for a long time that it has and approach 1 magnetic permeability (nonmagnetic a kind of measuring).Yet nearest emphasis is a low heat expansion property, rather than magnetic permeability.Along with the appearance of the improved high-performance color teletron of the height that is used for graphoscope in recent years, have been noted that microsize variation that electrod assembly causes along with thermal expansion can influence the picture quality (purity of color) of (see figure 1) on the display screen.In order to overcome this problem, the iron-nickel alloy of low bulk (particularly Fe-42%Ni alloy, i.e. 42 alloys) is as electrode materials.
Yet existing 42 alloys have the problem that forms burr.That is, when going out when having each 42 alloy electrode blank of one of aperture 10a, 10b and 10c with punch die respectively, form burr B (see figure 2) at the edge of aperture 10e (jumper bar is with the clout punching press and from the place of blank excision).The burr that forms during punching can have a negative impact to the dimensional precision (it must satisfy strict accuracy requirement) of electron gun parts.Because the reduction of proof voltage, abnormal discharge is extremely harmful to electron beam gun sometimes on the burr under high-voltage.Because the improvement day by day of chromoscope quality makes to the requirement that reduces burr on the electron gun parts more and more urgent.
So far, for example in Japanese Patent Application Publication 6-122945,6-184703,7-3400 and 7-34199 the punching performance to iron-nickel alloy improvement has been proposed.
In these applications, the content of open 6-184703 regulation sulphur is 0.002-0.05%, and is dispersed on the crystal boundary in the alloy material compound of sulphur or sulphur or intragranular.Yet percentage ratio in accordance with regulations only adds sulphur (a kind of easy cutting element) and is not enough to control the burr in the most accurate modern punch process.
Remaining open 6-184703,7-3400 and 7-34199 propose to add in alloy and strengthen element (as Ti, Nb, V, Ta, W and/or Zr), to give the fragility of higher hardness of alloy and appropriateness, to suppress the formation of burr.Yet this measure has produced owing to increasing the problem that hardness shortens Life of Punch Die and increases cost owing to these element-specific of adding.
The objective of the invention is to solve above-mentioned problems of the prior art, a kind of iron-nickel alloy that is used for electron gun parts is provided, this alloy has improved punching performance, but the life-span that does not shorten punch die does not have special elements and the increase expense yet.The present invention also provides the punched electron gun parts of being made by alloy through punching press, and (with the electron gun electrodes is representative.)。
The inventor has furtherd investigate the influence of minor constituent to the used iron-nickel alloy punching performance of electron gun parts.As a result, by controlling oxygen level and as required oxygen level and sulphur content being controlled the punching performance that has improved iron-nickel alloy within the limits prescribed, we have successfully solved the problems referred to above.The present invention does not produce the problem that shortens Life of Punch Die and increase the special elements cost.
Specifically, the invention provides a kind of iron-nickel alloy that is used for electron gun parts.This alloy comprises the Fe and the unavoidable impurity of 30-55% weight Ni, 0.5% weight or Si still less, 1.5% weight or Mn still less, 0.2% weight or Al still less, 0.005-0.020% weight O, 0.020% weight or S still less and surplus.The present invention also provides the punched electron gun parts made from above-mentioned iron-nickel alloy.The typical case of this electron beam gun punch components is an electron gun electrodes.
By oxygen level being controlled in the suitable scope, also contain an amount of sulphur (if necessary) simultaneously, can obtain having the iron-nickel alloy of good stamping performance.Oxygen exists with the inclusion form in the material mostly, and it has the effect that improves the material punching performance.Particularly, in punching operation, near the stress during shear deformation the punch die edge is increased to material always to begin till the fracture.This fracture preferentially takes place at the inclusion place, and the total content of inclusion is high more, just easy more fracture of material.Therefore, after the material punching press, fracture surface is higher than very, and the burr that produces is littler than regular situation.The compound of sulphur or sulphur is on the crystal boundary that is distributed in the alloy material or intragranular, and the result has improved its cutting ability.
Yet, add the erosion resistance that sulphur can reduce iron-nickel alloy, sometimes even cause in the assembling process of electron beam gun or produce the problem of corrosion in the storage process of material.In this case, suggestion is controlled at sulphur content below 0.002%.
Therefore, if only require in the present invention or major requirement raising punching performance that then sulphur content should be 0.002-0.020%, and in the time must considering to reduce erosion resistance, sulphur content should be lower than 0.002%.
Fig. 1 is the cross-sectional view of shadow mask type colour tube.
Fig. 2 (a) is the skeleton view of electron gun electrodes (example of punch components of the present invention), and Fig. 2 (b) is the cross-sectional view of being done along A-A ' line among Fig. 2 (a).
Fig. 3 is the Photomicrograph of explanation by the burr situation of punching press generation.(a) is the Photomicrograph of sample in the embodiment of the invention among the figure, (b) is the Photomicrograph of sample in the Comparative Examples.The both represents the pressworkability of these materials.
Explain now the reason that adds described number range alloying element according to the present invention.
(Ni): nickel is an important element that determines the iron-nickel alloy thermal expansivity. If the content of nickel is lower than 30% or be higher than 55%, because thermal coefficient of expansion is too high, this alloy is inapplicable. Therefore, the content of nickel is limited between the 30-55%.
(Si): mainly as deoxidier, it marginally appears in the field trash of iron-nickel alloy silicon. There is a small amount of silicon to exist better with the solid solution form, because it makes the iron-nickel alloy sclerosis and is easier to punching press. Silicon is unfavorable above 0.5% content, because can make the hardness of this alloy too high, and the life-span of shortening punch die. Therefore, the content of silicon is 0.5% or lower. Because above-mentioned reason, the content of silicon is preferably 0.005-0.5%.
(Mn): add manganese and generally be in order to promote deoxidation and to improve the hot-working character of alloy material. Therefore manganese forms MnO and MnS field trash, and by usually producing the Mn-Si-O field trash with pasc reaction. As silicon, manganese also makes iron-nickel alloy hardness increase. Therefore, it can improve the punching performance of alloy effectively. Yet, be unfavorable above 1.5% manganese, because it makes the hardness of alloy too high, thereby the life-span of shortening punch die. Therefore the content with manganese is controlled at 1.5% or lower, and considers that from improving the punching performance aspect content of 0.1-1.5% suits.
(Al): adding aluminium generally is for deoxidation. Therefore aluminium forms Al certainly2O
3Field trash. Aluminium also can make the iron-nickel alloy sclerosis, and effectively improves punching performance. Should avoid making the content of aluminium to surpass 0.2%, because this can make the hardness of alloy too high unfavorable to punch die. The content of aluminium is preferably 0.005-0.2%.
(O): it is generally acknowledged that oxygen is a kind of harmful element, so be that deoxidation is to containing below 0.005% oxygen to the conventional iron-nickel alloy that is used for electron gun parts. Yet, have now found that oxygen content is 0.005% or when more, has improved the punching performance of alloy. Because the oxygen more than 0.020% can make the break surface of punch components coarse, so oxygen content is limited between the 0.005-0.020%.
(S): as the open 6-184703 of patent application disclosed, sulphur was a kind of element that can improve the alloy punching performance, and was 0.002% or shows its effect more for a long time at content.When sulphur adds fashionable (as in the present invention) with oxygen, the sulphur content more than 0.020% can make fracture surface too coarse.Therefore, when only requirement or major requirement improve punching performance, sulphur content is defined as 0.002-0.020%.On the other hand, sulphur is again a kind of element that reduces alloy corrosion resistance.Sulphur content is that the alloy more than 0.002% produces the problem of corrosion sometimes, as when when transport in the water route or when being stored in the storehouse of nearly water.In this case, sulphur content is defined in below 0.002%.
Composition beyond the mentioned component then is unavoidable impurity and iron.Impurity described here is meant general contained impurity, comprises carbon, phosphorus and copper.These impurity have adverse influence to expansion character, and itself is unfavorable for punching performance.Yet in fact they form very little non-metallic inclusion, as P
2O
5And Cu
2S, these inclusiones all can improve punching performance.The total content of these impurity elements should be between 10-2000ppm.
The inventor has studied each component of iron-nickel alloy to making the used alloy punching Effect on Performance of electron gun parts.The research of being done discloses: by oxygen level being controlled at suitable scope (from general in the art general knowledge, this scope is seemingly excessive) in, simultaneously also allow to contain an amount of sulphur (if necessary), can obtain having the iron-nickel alloy of good stamping performance.Oxygen exists with the inclusion form in the material mostly, can improve the punching performance of material.In punching operation, near the stress during shear deformation the punch die edge is increased to material always to begin till the fracture.This fracture preferentially is that the inclusion place takes place, and the total content of inclusion is high more, just easy more fracture of material.Therefore, fracture surface is higher than very after the material punching press, and the burr that produces is littler than regular situation.The compound of sulphur or sulphur is on the crystal boundary that is distributed in the alloy material or intragranular, and the result has improved its cutting ability.
The manufacturing processed of alloy is as follows: to scale each constituent materials is melted together, make the iron-nickel alloy ingot.With the alloy pig homogenizing annealing, hot rolling, annealing and cold rolling repeatedly then is until final thickness.After carrying out last annealing, be made into the punched blank that thickness is about the 0.05-0.5 millimeter.On punch press, this blank is carried out punching press (can be with or without coining manipulation) and make electron gun parts.
Now the present invention is further illustrated in conjunction with following embodiment and Comparative Examples.
Embodiment 1
In vacuum tightness is 1.33 * 10
-3-13.3Pa (10
-5-10
-1Torr) in the vacuum induction melting stove, each constituent materials is melted together, make every heavy 6 kilograms Fe-Ni alloys ingot of main iron content and 42% nickel.Is mixing such as high pure electrolytic copper, press working steel sheet steel waste material, sulphur free-cutting steel, rimming steel waste material, electrolytic nickel, electrolytic manganese in different ratios with various raw materials, so that change the content of sulphur, oxygen etc. in the alloy material.
With each steel ingot homogenizing annealing, then at 1200 ℃ of sheet materials that are rolled into 4 mm thick.With this sheet material annealing, pickling, be cold-rolled to 1.5 mm thick.Again this sheet material is lighted annealing, the sheet material of cold rolling one-tenth 0.4 mm thick.At last, sheet material in a vacuum in 750 ℃ of annealing 1 hour, is obtained sample.
Measure punching performance as follows, promptly going out 10 diameters with 30 tons of punch presses on each sample is that 0.4 millimeter, spacing are 3 millimeters aperture, measures the maximum ga(u)ge of the burr that punching press produces and the fracture surface ratio of maximum height and stamping surface then.Table 1 has been listed the chemical constitution of each embodiment and Comparative Examples alloy material, maximum ga(u)ge and the maximum height and the fracture surface ratio of sample burr.Described term " burr thickness " is meant from the outer end of the jagged burr unilateral observation burr in hole from the distance (projecting length) of punching hole periphery." height of burr " is meant from the outer end of aperture cross-sectional view burr from the distance (projecting length) of punching hole bottom surface." fracture surface is than (%) " is defined as:
(fracture surface thickness/sheet metal thickness) * 100
Table 1
| Numbering | Chemical constitution (% weight) | Burr maximum ga(u)ge (μ m) | Burr maximum height (μ m) | Fracture surface is than (%) | The fracture surface state |
| Ni | Si | Mn | Al | O | S | Fe |
| 1 2 3 4 5 6 7 | 40.8 41.8 41.2 41.2 40.9 41.0 41.2 | 0.05 0.03 0.02 0.01 0.02 0.06 0.04 | 0.46 0.42 0.47 0.51 0.39 0.45 0.45 | 0.010 0.007 0.004 0.001 0.006 0.009 0.012 | 0.007 0.009 0.012 0.017 0.008 0.006 0.007 | 0.003 0.003 0.003 0.003 0.007 0.011 0.018 | Surplus surplus surplus surplus surplus surplus surplus | 15 13 12 9 11 13 11 | 5 5 3 2 2 2 2 | 25.5 26.0 25.7 29.3 27.7 25.8 26.6 | Good good good |
| 8 9 10 11 12 13 | 41.4 40.7 41.0 41.3 40.9 41.4 | 0.27 0.19 0.15 0.01 0.01 0.01 | 0.50 0.41 0.48 0.17 0.34 0.22 | 0.046 0.061 0.035 0.001 0.001 0.001 | 0.003 0.004 0.004 0.023 0.011 0.025 | 0.001 0.002 0.005 0.003 0.031 0.024 | Surplus surplus surplus surplus surplus surplus | 58 38 34 10 11 8 | 14 12 12 2 2 2 | 8.4 10.1 16.7 29.2 28.1 31.5 | Well not OK bad |
Fig. 3 is the punching hole Photomicrograph of taking from burr one side.(a) is the Photomicrograph of sample in the one embodiment of the invention among the figure, (b) is the Photomicrograph of sample in the Comparative Examples.
From table 1 and Fig. 3 as can be known, the sample in all embodiment of the invention, all the sample than Comparative Examples is little for the maximum ga(u)ge of its burr and the biggest ground, and the burrization when this shows punching press has obtained obvious suppression.In addition, sample of the present invention has higher fracture surface ratio and better punching performance than Comparative Examples 8 and 10 samples.The fracture surface of Comparative Examples 11 and 12 (oxygen level or sulphur content all surpass the upper limit of the scope of the invention) is too coarse.Because oxygen level and sulphur content all surpass set upper limit of the present invention, so the fracture of sample is too coarse in the Comparative Examples 13, therefore, also are inappropriate.
Therefore, the present invention can provide the electron gun parts of being made by a kind of iron-nickel alloy, this alloy can be controlled at the burr maximum ga(u)ge below 15 millimeters during punching press, the burr maximum height is controlled at below 5 millimeters, the fracture surface ratio is controlled in 25%, simultaneously fracture surface is remained on slick good state.
Embodiment 2
In order to confirm to reduce the improvement effect of sulphur content to several alloys of making by embodiment 1 similarity method, carry out 24 hours salt spray test at 35 ℃ with 5% salts solution, observe whether corrosion to take place.The results are shown in Table 2.
Table 2
| Numbering | Chemical constitution (% weight) | Burr maximum ga(u)ge (μ m) | Burr maximum height (μ m) | Fracture surface is than (%) | The fracture surface state | Salt spray coupon results |
| Ni | Si | Mn | Al | O | S | Fe |
| 1 5 6 7 | 41.1 40.8 40.9 41.4 | 0.04 0.03 0.01 0.01 | 0.45 0.42 0.46 0.39 | 0.009 0.007 0.003 0.001 | 0.008 0.010 0.013 0.018 | 0.001 0.001 0.001 0.001 | Surplus surplus surplus surplus | 22 18 16 15 | 8 6 4 4 | 20.2 21.0 22.4 23.1 | Carefully | Carefully |
| 8 9 12 13 | 41.4 40.7 41.0 42.2 | 0.27 0.01 0.03 0.04 | 0.50 0.48 0.45 0.36 | 0.046 0.001 0.010 0.008 | 0.003 0.026 0.008 0.009 | 0.001 0.001 0.003 0.005 | Surplus surplus surplus surplus | 58 14 15 12 | 14 3 5 4 | 8.4 23.7 25.7 26.3 | Good job carefully | Corrosion corrosion carefully |
During salt spray test, sulphur content be reduced to 0.001% and oxygen level be controlled at the scope of the invention and corrosion do not take place to D with interior alloy A, also keep simultaneously higher fracture surface than and punching performance preferably.Sulphur content is respectively 0.003% and 0.005% alloy G and H corrosion has then taken place.Alloy E and F are used for contrast.Alloy E is equivalent to suppress among the embodiment 1 alloy 8 of oxygen level, and it shows bigger burr maximum ga(u)ge and maximum height value.The excessive alloy F of oxygen level then has too coarse fracture surface.
From above-mentioned description as can be known, the iron-nickel alloy of the present invention that is used for electron gun parts has obviously improved punching performance.They can solve the problems such as electron beam gun proof voltage reduction that the undesired discharge because of burr on the punching press edge causes, and the electron gun parts that can the production dimensional precision significantly improves, to satisfy the needs of large-size high-quality chromoscope development in recent years.