Microhardness variation in relation to carbide development in heat treated Cr3C2-NiCr thermal spray coatings

被引:120
作者
Matthews, S [1 ]
Hyland, M [1 ]
James, B [1 ]
机构
[1] Univ Auckland, Dept Chem & Mat Engn, Auckland, New Zealand
关键词
aging; isothermal heat treatment; cermets; hardness; thermal spray coatings;
D O I
10.1016/S1359-6454(03)00254-4
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Cr3C2-NiCr thermal spray coatings have been extensively used to mitigate high temperature wear. During deposition compositional degradation occurs through dissolution of the carbide phase into the matrix. High temperature exposure leads to transformations in the microstructure, which influences the coating microhardness. While such developments have been investigated in short-term trials, no systematic long-term investigations of the microhardness variation as a function of microstructural development have been presented. In this work, high velocity sprayed Cr3C2-NiCr coatings were heat treated at 900 degreesC for up to 60 days in air and argon. With treatment, matrix phase supersaturation was reduced, while widespread carbide nucleation and growth generated an expansive carbide skeletal network. An initial softening of the coatings occurred through matrix phase refinement, the subsequent hardness recovery was a function of carbide development. Treatment in air generated further hardness increases as a result of internal oxidation. (C) 2003 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:4267 / 4277
页数:11
相关论文
共 24 条
[1]  
Akimoto K., 1995, THERMAL SPRAY CURREN, P313
[2]  
[Anonymous], THERM SPRAY 2002 P I
[3]   A model for the hardness of cemented carbides [J].
Engqvist, H ;
Jacobson, S ;
Axén, N .
WEAR, 2002, 252 (5-6) :384-393
[4]   Multilayer coatings by continuous detonation system spray technique [J].
Fagoaga, I ;
Viviente, JL ;
Gavin, P ;
Bronte, JM ;
Garcia, J ;
Tagle, JA .
THIN SOLID FILMS, 1998, 317 (1-2) :259-265
[5]  
FELBECK DK, 1968, PRENTICE HALL SERIES
[6]   Microstructural examination of HVOF chromium carbide coatings for high-temperature applications [J].
Guilemany, JM ;
Nutting, J ;
LlorcaIsern, N .
JOURNAL OF THERMAL SPRAY TECHNOLOGY, 1996, 5 (04) :483-489
[7]  
GUILEMANY JM, 1997, THERMAL SPRAY UNITED, P717
[8]  
GURLAND J, 1984, PRACTICAL APPL QUANT, P65
[9]   Precipitation phenomenon in nanostructured Cr3C2-NiCr coatings [J].
He, JH ;
Lavernia, EJ .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2001, 301 (01) :69-79
[10]   Thermal stability of nanostructured Cr3C2-NiCr coatings [J].
He, JH ;
Ice, M ;
Schoenung, JM ;
Shin, DH ;
Lavernia, EJ .
JOURNAL OF THERMAL SPRAY TECHNOLOGY, 2001, 10 (02) :293-300