Sintering of Ti(C,N)-WC/Mo2C-(Ta,Nb)C-Co/Ni Cermets Investigated by CO and N2 Outgassing

Metals

Viktoria Schwarz¹  Fabio Scagnetto¹  Walter Lengauer¹ 

[1] Institute for Chemical Technologies and Analytics, Vienna University of Technology, A-1060 Vienna, Austria;

关键词: titanium carbonitride;    Ti(C,N);    composite;    cermet;    mass spectrometry (MS);    sintering;    nitrogen;    sintering atmosphere;   

DOI  :  10.3390/met9040427

来源: DOAJ

【 摘 要 】

Cermets of the type Ti(C,N)-WC/Mo₂C-(Ta,Nb)C-Co/Ni with changing [Mo]/([Mo] + [W]) ratio were subjected to an investigation of outgassing of CO and N₂ upon sintering. Quantification of CO and N₂ was performed by gas calibration, measurement of masses 12 (¹²C), 14 (¹⁴N) and 28 (²⁸CO and ²⁸N₂), as well as C, N, O analysis of the samples before and after sintering. The formation of CO occurs at lower temperatures than that of N₂, both gases being completely evolved already at solid-state sintering conditions. If pre-alloyed powders are employed in the starting formulation, the amount of evolved gases is substantially reduced, because part of the formation of mixed hard phases is anticipated. Changing binder composition from Co:Ni = 1:1 to 2:1 and 3:1 does not change the outgassing characteristics, while different batches of nominally the same Ti(C,N) powder can have significant influence. Mass spectrometry is a most valuable in situ tool for getting insight into the metallurgical reactions occurring upon sintering. These reactions result in the typical microstructure and influence the properties of cermets.

【 授权许可】

Unknown