| 摘要 |
PURPOSE:To make it possible to obtain sufficient performance by relatively-low- temperature and short-time procession without the need for power removal by changing an amorphous boron coating layer, applied to the surface of a diaphragm base made of titanium, into a hard film. CONSTITUTION:The surface of diaphragm base 4 made of titanium is applied with amorphous boron to form a coating layer of it. Diaphragm base 4 having the amorphous boron coating layer like this is contained in vacuum container 7. Alkali earth metal powder 6 is also placed in vacuum container 7, which is evacuated and heated. When magnesium powder is used as earth metal powder 6, container 7 is filled with magnesium vapor at a heating temperature of about 1,000 deg.C. Then, the amorphous coating layer has the gap of amorphous boron powder filled with boron atoms carried by the magnesium vapor and changes into boron film 15 of glass. In titanium layer 1, boron atoms are diffused and boron diffused layer 3 is formed on the surface of titanium layer 1. |
