摘要:
A tungsten wire containing 1 to 10% by mass of rhenium has a point which indicates a 2% elongation within a quadrangle formed by joining points with straight lines, where the values of x and y are point (20, 75), point (20, 87), point (90, 75), and point (90, 58), in this order, wherein the wire diameter of the aforementioned tungsten wire is represented by x nullm, and the elongation of the tungsten wire is 2% after electrically heating with an electrical current which is a ratio of y % to the fusion current (FC) at the wire diameter x nullm, and wherein a semi-logarithmic system of coordinates is expressed by a horizontal axis using a logarithmic scale of the aforementioned wire diameter x and a vertical axis using a normal scale of ratio y to the fusion current. According to the above-described configuration, a tungsten wire having a great elongation even under conditions of high temperature can be provided, and the tungsten wire can exhibit an excellent durability when used as component material for constituting cathode heaters and so forth, and the tungsten wire can be manufactured efficiently.
摘要:
In a heater for an indirectly-heated cathode having a double helical structure, a film which can be removed by heating at the temperature of 250.degree. to 350.degree. C. is disposed between adjacent portions in a vertical direction, of a helical core wire coated with an insulating layer. Since this film is disposed, the occurrence of cracks in the insulating layer can be prevented so that the insulating property between the heater and a cathode sleeve do not gel deteriorated and clogging of an electron beam aperture of a shadow mask can be prevented, too.
摘要:
One embodiment provides a tungsten wire containing 1 to 10% by mass of rhenium, the wire having a point indicating a 2% elongation within a quadrangle formed by joining points with straight lines, where the values of x and y are point (20, 75), point (20, 87), point (90, 75), and point (90, 58), in this order; wherein the wire diameter of the tungsten wire is represented by x μm, and the elongation of the tungsten wire is 2% after electrically heating with an electrical current which is a ratio of y % to the fusion current (FC) at the wire diameter x μm, and wherein a semi-logarithmic system of coordinates is expressed by a horizontal axis using a logarithmic scale of the wire diameter x and a vertical axis using a normal scale of ratio y to the fusion current.
摘要:
There is provided a method for fabricating an indirectly-heated cathode structure, including the steps of inserting a heater formed in a predetermined shape into a space of a mold, injecting a thermoplastic resin into the space of the mold to mold the heater by the thermoplastic resin, inserting the heater molded by the thermoplastic resin into a sleeve having a cap on its top end, connecting the sleeve and the heater by means of a support body to assemble a cathode structure, and heating the cathode structure to remove the thermoplastic resin used for molding the heater. Therefore, in an indirectly-heated cathode structure, a heater deviating from center can be prevented, and it is easy to adjust the gap between a heater, a sleeve and a cap. Thus, the heater can be positioned at a desired position inside the sleeve, thereby preventing current leakage from being generated due to a breakdown in the heater. In particular, the sleeve and the cap can be uniformly heated, thereby reducing a local difference in the thermion emitting density.