Plasma CVD of hard coatings Ti(CNO) using metallo-organic compound Ti(OC3H7)(4)

The use of the metallo-organic compound Ti(OC3H7)(4) with auxiliary heating plasma CVD (MOPCVD) of hard coatings Ti(CNO) is reported. The harmful effe ct of chlorine on the film properties and on the PCVD equipment could be av oided in this way. The deposition rate decreased from 2.4 to 1.2 mum/h when the oven temperature ranged from 120 to 420 degreesC, and the maximum micr ohardness value of the Ti(CNO) coatings can reach 16 000 MPa. The coatings were analyzed with SEM and XRD. The coatings showed the typical columnar st ructure. The XRD analysis revealed that the d(200)-values of the Ti(CNO) fi lms decreased from 0.2130 to 0.2123 nm with increasing the oven temperature . The chemical composition of the films was measured by XPS. The films were mainly composed of titanium, carbon, nitrogen and oxygen. The bonding ener gies of Ti2p3/2 and Ti2p1/2 of the Ti(CNO) films were 458.70 and 463.75 eV, respectively The cutting tests have shown that the average lifetime of phi 65 mm HSS drills coated with the MOPCVD-Ti(CNO) was 7.3 times as long as t hat of uncoated ones; the average lifetime of phi 65 x 5 mm HSS milling cut ter coated increased by a factor of 8. (C) 2000 Elsevier Science S.A. All r ights reserved.