Effect of TiC content on the carbide particle growth of NbC-Ni cemented carbide

The current study reports the influence of TiC addition on carbide particle growth of NbC-Ni cemented carbides. Microstructural analysis after liquid phase sintering in vacuum at 1420 °C for 40 min showed a decrease in NbC grain size as TiC content increased, associate to a change in NbC carbide mor...

Full description

Saved in:
Bibliographic Details
Published in:International journal of refractory metals & hard materials 2022-06, Vol.105, p.105826, Article 105826
Main Authors: da Costa Morais, Luara, Beneduce, Flavio, Magnabosco, Rodrigo, da Silva, André Luiz Nunis
Format: Article
Language:English
Subjects:
Cemented carbide
Cemented carbides
Chemical composition
DICTRA® simulation
Grain size
Liquid phase sintering
Liquid phases
Microstructural analysis
Niobium carbide
Phase composition
Titanium carbide
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The current study reports the influence of TiC addition on carbide particle growth of NbC-Ni cemented carbides. Microstructural analysis after liquid phase sintering in vacuum at 1420 °C for 40 min showed a decrease in NbC grain size as TiC content increased, associate to a change in NbC carbide morphology from rounded to equiaxed. Chemical composition from EDS analysis revealed a mixed carbide (Nb,Ti)C formation, with a gradient of Ti in carbide region for samples with TiC above 15%. Dictra® simulations of spherical particles immersed in Ni matrix evidenced a retardation in carbide dissolution and a decrease in the volume dissolved as TiC is added. It was also noted that liquid phase composition for 140 min showed less Nb in liquid phase available for reprecipitation during cooling process, promoting carbide particle growth inhibition. Ti profiles from Dictra® and carbide composition from EDS suggest a thin Ti rich layer formation in carbide/binder interface, which can be related to the carbide particle growth inhibition mechanism. TiC addition promote an increase in hardness and toughness values, and the highest values for both properties was found for 7%TiC-NbC-12%Ni composition (mass percent). •TiC addition promoted grain size reduction in NbC-Ni cemented carbide sintering at 1420 °C.•A mixed (Nb,Ti)C carbide is formed when TiC is added up to 30%.•A decrease in Nb content in liquid region is observed as TiC is added by DICTRA® simulations results.•The hardness and fracture toughness of NbC-based cemented carbides can be improved by TiC addition to the starting powder.
ISSN:0263-4368
2213-3917
DOI:10.1016/j.ijrmhm.2022.105826