Molybdenum alloy and X-ray tube using the molybdenum alloy rotating anode target, X-ray tube and molten crucible
In the past, as a molybdenum (Mo) alloy to improve high temperature strength, it is known that TZM alloy is composed of 0.5wt % Ti, 0.07wt % Zr, 0.05wt % C, and the rest is Mo. TZM alloy has excellent high temperature strength due to the high melting point of molybdenum as the main component. This characteristic is used in the fields requiring high temperature strength characteristics such as the melting crucible used in the melting of rotating anode targets of X-ray tubes and metals.
However, when the TZM alloy is used to rotate the anode target of the X-ray tube, the impurities oxygen, carbon, hydrogen and so on in the alloy are vaporized, and the so-called vacuum degree in the X-ray tube is reduced and the characteristics of the X-ray tube are reduced. Similarly, even for molten crucibles, inappropriate situations can occur in which the so-called gas components emitted in the melting contaminate the melt. In this way, for example, in the environment used at high temperatures above 800 ℃, or even above 1200 ℃, the so-called inappropriate situation caused by the gas composition in the alloy occurs.
X-ray tubes are used in X-ray inspection devices in various fields, such as CT inspection devices for medical purposes and non-destructive inspection devices for carry-on baggage inspection. The X-ray tube can detect the X-rays generated by the beam surface by making the axis (rotation axis) and the rotating anode with the beam surface of the rotating anode target to rotate at a high speed of about 6000 ~ 10000rpm while irradiating the electron beam. In recent years, it is hoped that the X-ray inspection device can have high output and high clarity. In order to achieve high output and high clarity, it is considered to make the rotating anode target large. The diameter of the general rotating anode target is about 40 ~ 100mm. Make it more than 100mm in diameter and carry out large-scale. When large-scale, the rotating anode target becomes heavier during the assembly process, and a large load is applied when it is fixed to the shaft.
