Comparison of auxiliary cathode and conventional plasma nitriding of gamma-TiAl alloy

被引：9
作者：
Ahmadi, M. [1 ]
Hosseini, S. R. [1 ]
Hadavi, S. M. M. [1 ]
机构：
[1] Maleke Ashtar Univ Technol, Dept Mat Engn, Esfahan 83145115, Iran
来源：
VACUUM | 2016年 / 131卷
关键词：
Gamma titanium aluminide; Surface modification; Plasma nitriding; Hallow cathode effect; TITANIUM ALUMINIDES; STEEL; TI-6AL-4V; HYDROGEN; BEHAVIOR; OXYGEN; TIME; AL;
D O I：
10.1016/j.vacuum.2016.06.006
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
Effect of auxiliary cathode (ACN) and conventional plasma nitriding (CPN) processes on surface modification of gamma-TiAl has been investigated. Both processes were done at temperature of 800 degrees C under gas ratio of N-2/H-2 = 1. The process duration was selected to be 3, 6 and 9 h for ACN, while it was 10, 20 and 30 h for CPN. Characterizations of the microstructure, phases, elemental distribution and hardness were performed using FESEM, XRD, GDOES, RBS and microhardness tests. Ti(2)AIN and TiN phases were detected as the main nitride compounds in both processes. Passive oxide films disrupted diffusion of nitrogen atoms in CPN process; hence a narrow nitrided zone was formed due to this surface oxidation. Higher ion intensity and oxidation protection emphasized the ACN process. The thicker and more uniform compound layers with more surface hardness were achieved using the auxiliary cathode. About 70% of nitriding process time was saved by ACN, in comparison with the CPN process. (C) 2016 Elsevier Ltd. All rights reserved.
引用
收藏
页码：89 / 96
页数：8
相关论文
共 31 条
[1]   Effect of workpiece geometry on the uniformity of nitrided layers [J].
Alves, C ;
da Silva, EF ;
Martinelli, AE .
SURFACE & COATINGS TECHNOLOGY, 2001, 139 (01) :1-5
[2]  
Appel F, 2011, GAMMA TITANIUM ALUMINIDE ALLOYS: SCIENCE AND TECHNOLOGY, P1, DOI 10.1002/9783527636204
[3]   METALLOGRAPHY OF GAMMA-TITANIUM ALUMINIDES [J].
BAESLACK, WA ;
MCQUAY, PA ;
LEE, DS ;
FLETCHER, ED .
MATERIALS CHARACTERIZATION, 1993, 31 (04) :197-207
[4]   Tribological properties of duplex plasma oxidised, nitrided and PVD coated Ti-6Al-4V [J].
Cassar, G. ;
Banfield, S. ;
Wilson, J. C. Avelar-Batista ;
Housden, J. ;
Matthews, A. ;
Leyland, A. .
SURFACE & COATINGS TECHNOLOGY, 2011, 206 (2-3) :395-404
[5]   Ion nitriding of titanium aluminides with 25-53 at.% Al .1. Nitriding parameters and microstructure characterization [J].
Chu, CL ;
Wu, SK .
SURFACE & COATINGS TECHNOLOGY, 1996, 78 (1-3) :211-218
[6]  
de Sousa R.R.M., 2011, J METALL, V2012, P1
[7]  
Dionysio M.O., 2010, SURF COAT TECH, V204, P3623
[8]  
Doering R., 2008, HDB SEMICONDUCTOR MA
[9]   Oxygen, hydrogen, and deuterium effects on plasma nitriding of metal alloys [J].
Figueroa, CA ;
Weber, S ;
Czerwiec, T ;
Alvarez, F .
SCRIPTA MATERIALIA, 2006, 54 (07) :1335-1338
[10]   Oxygen Effects in Plasma Nitriding of Ferrous Alloys [J].
Figueroa, Carlos A. ;
Weber, Sylvain ;
Czerwiec, Thierry ;
Alvarez, Fernando .
PLASMA PROCESSES AND POLYMERS, 2007, 4 :S732-S735
1234