|
Descripción
|
|
|---|---|
| INTRODUCTION In the recent few decades, although there have been relevant advances in new forming techniques, machining is still a predominant industrial activity [1]. However, the components of traditional tool materials, based on WC-Co, are considered critical raw materials; thus, both industry and academy are actively searching alternative compositions to fulfill its requirements. In this context, iron matrix cermets with TiCN-based hard phases are gaining considerable attention for their unique combination of physical and mechanical properties, in spite of the poor interfacial cohesion between the metallic phase and the ceramic particles. To overcome such limitations, the addition of alloying elements such as Ni and C aims to improve the wetting behaviour between both phases during the liquid phase sintering while hindering the ceramic particles growth [2]. METHODS In this work, the influence of both carbon additions and metallic phase fraction on the microstructure, densification and mechanical properties of Ti(C,N)-based cermets, has been evaluated. Materials were produced with a Ti(C,N) content ranging between 70 and 80 vol %, in a Fe-Ni alloy matrix with 0.5 to 1 wt% carbon. Ready-to-press granules were produced by colloidal techniques to prepare aqueous suspensions of particles followed by spray-dry. Granules were pressed in a uniaxial die and sintered in vacuum at 1450 °C for 2 h. The main cermets parameters such as phase distribution, densification or hardness were studied by means of image analysis of scanning electron micrographs and nanoindentation measurements. In addition, its mechanical performance evaluated was three-point-bending tests up to 800 °C, on smooth and notched specimens. RESULTS It has been shown that the flexural strength of Ti(C,N)-Fe cermets can improve significantly with the addition of 1 vol% carbon, and this observation was maintained in all the temperature range tested, from RT to 800 °C. On the contrary, the higher content of the ceramic phase (80 vol% vs 70 vol%) can lead to an increase in both hardness and elastic modulus, owing to the presence of stiffer elements. However, the highest values fracture toughness, with values ranging between ?12 and ?15 MPa m1/2, were observed for cermets containing a higher percentage of metallic binder, whilst the addition of extra carbon additions seems to have no influence on this property. References [1] Y. Peng, H. Miao, Z. Peng, Development of TiCN-based cermets: Mechanical properties and wear mechanism, Int. J. Refract. Met. Hard Mater. 39 (2013) 78?89. doi:10.1016/j.ijrmhm.2012.07.001. [2] M. Dios, I. Kraleva, Z. González, P. Alvaredo, B. Ferrari, E. Gordo, R. Bermejo, Mechanical characterization of Ti(C,N)-based cermets fabricated through different colloidal processing routes, J. Alloys Compd. 732 (2018) 806?817. doi:10.1016/j.jallcom.2017.10.274. | |
|
Internacional
|
Si |
|
Nombre congreso
|
EUROMAT 2019 |
|
Tipo de participación
|
960 |
|
Lugar del congreso
|
Estocolmo |
|
Revisores
|
Si |
|
ISBN o ISSN
|
0000-0000 |
|
DOI
|
|
|
Fecha inicio congreso
|
01/09/2019 |
|
Fecha fin congreso
|
06/08/2019 |
|
Desde la página
|
1987 |
|
Hasta la página
|
1987 |
|
Título de las actas
|
EUROMAT 2019 Conference Procedings |