| 摘要 |
<p>PCT No. PCT/DE95/00449 Sec. 371 Date Sep. 27, 1996 Sec. 102(e) Date Sep. 27, 1996 PCT Filed Apr. 1, 1995 PCT Pub. No. WO95/32317 PCT Pub. Date Nov. 30, 1995A tool is made in a coating vessel, depositing upon the base tool body of a hard metal or cermet, a coating by chemical vapor deposition by admitting to the vessel a reactive gas mixture capable of forming a composition selected from the group which consists of aluminum oxide and of titanium and zirconium carbide, nitride and carbonitride, and of mixtures thereof at a chemical vapor deposition pressure and temperature; and interrupting the chemical vapor deposition by a multiplicity of times by replacing the reactive gas mixture with a nonreactive gas mixture containing components selected from the group which consists of argon, hydrogen, nitrogen and mixtures thereof, lowering a pressure in the vessel to a plasma chemical vapor deposition pressure of 10 to 1000 Pa, effecting a glow discharge at the body with the body being cathodically connected at a negative D.C. voltage of 200 to 1000 volts for a period of 1 to 30 minutes, to effect plasma chemical vapor deposition coating between chemical vapor deposition coating with the reactive mixture.</p> |
