Deposition of hard crystalline Al2O3 coatings by bipolar pulsed dc PACVD

被引：72

作者：

Taschner, C

Ljungberg, B

Alfredsson, V

Endler, I

Leonhardt, A

机构：

[1] Inst Festkorper & Werkstofforsch Dresden, DE-01171 Dresden, Germany

[2] AB SAndvik Coromant, SE-12680 Stockholm, Sweden

[3] Univ Lund, SE-22100 Lund, Sweden

来源：

SURFACE & COATINGS TECHNOLOGY | 1998年 / 108卷 / 1-3期

关键词：

PACVD; Al2O3;

D O I：

10.1016/S0257-8972(98)00561-1

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

A bipolar pulsed d.c. PACVD technique was used to deposit crystalline Al2O3 coatings onto WC/Co cemented carbide cutting inserts and onto steel substrates using a gas mixture of AlCl3, H-2, O-2 and Ar. Different deposition conditions were tested, substrate temperatures (T-s) between 500 and 700 degrees C and a gas mixture ratio O/AlCl3 in the range from 2 to 20. At T(s)greater than or equal to 600 degrees C transparent crystalline coatings of the gamma-Al2O3 phase were obtained having the best crystallinity for O/AI ratio of 4 and 6. At a substrate temperature of 700 degrees C and an O/AlCl3 ratio of 2, alpha-Al2O3 or a mixture of alpha- and gamma-Al2O3 phases was formed. The microhardness HV[0.02] of the crystalline coatings was found to be in the range 19-23 GPa. The gamma-Al2O3 layers appeared in most cases transparent with smooth surfaces. The wear properties of Al2O3-coated cutting inserts produced by the PACVD method were evaluated and compared with a thermal CVD kappa-Al2O3 coating in a machining test in a ball bearing steel. From the test results it could be concluded that the PACVD Al2O3 coatings showed wear properties very similar to the thermal CVD kappa-Al2O3 coatings. (C) 1998 Elsevier Science S.A. All rights reserved.

引用

页码：257 / 264

页数：8

共 12 条

[1] New PACVD-hard material layers for wear protection of high-speed steel [J].