電子ビーム溶接の溶込み深さに関する研究(第4報)
溶融部からの電子量と溶込み深さの関係
1977 年 46 巻 10 号 p. 721-727
詳細
1977 年 46 巻 10 号 p. 721-727
It can be supposed that there are many particles emitted from molten metal during electron beam welding and that amount of these particles depends largely upon the state of molten metal. In order to detect the penetration depth or state of fusion zone, we tried to capture those particles, especially electrons using copper electrodes, named probes, disposed near molten metal and negatively biased with respect to specimen. Comparison between probe current and penetration depth or state of spouting vapor was carried out. Results obtained are summerized as follows;
1) Energy of most electrons captured by probe is very small, less than 1 eV.
2) Probe current consists of a DC component and AC components of various frequencies.
3) The DC component relates closely to macroscopic penetration depth.
4) Probe current also relates closely to vapor spouting from molten metal, so that probe current represents macroscopic state of fusion zone.
5) An AC component of frequency range between 50 and 100 Hz. corresponds to ripple line or solidification line of fusion zone of metal and displays movement of molten metal.
