Prakt. Met. Sonderband 52 (2018) 337 
iS TOM Gar 
iM ang lattice parameters of MoC and WC as compared to TiC [11]. Fig. 3b depicts the (111) peaks 
Sta Nu of TiC and (Ti,M)C. With increasing HIP time, the reaction phase peaks grow compared to 
their associated TiC peaks. This finding could be corroborated by fitting the TiC / (Ti,M)C 
doublet peaks as depicted exemplarily in Fig. 3c. The normalized integrated intensities of 
Nase the (Ti,M)C phase gı,xro were found to increase from 30, 39 to 48 % for 3.5, 6.0 and 24 h, 
RTE respectively. 
— | Otter 
Capt Boe i! area 
Shc she iGo) 
5 — (HN TIC 
| „3 : ; “nie mpm 
; ES 8 
li =F 
+ 18 accord vs BE 
ve i + 2 J N= 
1). The reaction 5 A 65 70 a. 5 5 I „8 
"ot completly 2273 4 211 
38 Consoli 
No Fig. 3: XRD analysis of M7 + 10 vol.% TiC samples HIPed for different times as well as 
aml, dec the original TiC-powder. (a) Overview of the complete scanning area, (b) details of the 
0g he phase according (111) carbide peaks and fit details of the 24 h sample. 
fon 0, tt Both methods show the same trend of a continuously growing reaction phase by increasing 
HIP time as shown in Fig. 4. However, reaction kinetic slows down towards higher HIP times. 
The growth of reaction phase is considered to be limited by the diffusion rate of reaction 
phase forming elements, such as V, W or Mo from matrix and Ti as well as C from the TiC 
particle. At lower HIP times (e.g. 3.5 and 6.0 h) most of the TiC particle surface is not 
covered by (Ti,M)C and therefore diffusional transport of Ti and C can be achieved by 
accelerated interface diffusion. With increasing HIP time, the fraction of TiC covered by 
(Ti, M)C also increases. Thus, the distance for interface diffusion elongates or even the 
slower bulk diffusion through (Ti,M)C becomes more predominant. As a result, it is 
suggested that the formation rate decreases due to slower diffusional mass transport. 
Similar results regarding reaction kinetics were found e.g. for hot extruded cold work tool 
steel with WC reinforcements [12]. 
a 
7 
30 
TIC in blue, 25 © 
nich, Ce 
8 ty nem {10 
to analyze the ce oe 5 
ducted on the — ok 5 5 
overview of the HIP time [h] 
all as the (110) 
„Jose tothe TiC Fig. 4: Comparison of reaction phase development over different HIP times as assess 
sould. thus, be via farem and gi xro. 
se. The smaler 
VC and similar 
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