Prakt. Met. Sonderband 52 (2018) 129 
3. Results and Discussion 
3.1. MICROSTRUCTURE 
Ufacyy 
168 ll 3.1.1 METALLOGRAPHIC INVESTIGATIONS 
in 
Teatm 
is 8 The hardness measurements (HV1) of all specimens were performed on the 
fr metallographic cross sections. The hardness of the initial condition (as-cast) was found to 
be HV1 = 544. The annealing of the sample at 700 °C for 2 h, at 800 °C for 20 h and at 
900 °C for 20 h successively decreases the hardness that hints to a more homogenous 
HECHANIC microstructure with an even better ductility. The hardness after annealing at 900 °C for 
A 20h decreased up to HV1=483. Fig. 1 shows microstructure of different specimens after 
heat treatment. One recognizes different areas with segregations and relatively coarse 
phases. These constituents could not be dissolved even during the long time annealing at 
900 °C. The annealed areas shown at higher magnification present a phase with a fan-like 
nding by shape. After the heat treatment at higher temperature (900 °C), this phase tends to be 
fim, ye coarser than after the heat treatment at 800 °C (Fig. 1c and Fig. 1e). 
stg 
Samples were 
and etched jy 
Second-phage 
Tet from Leica 
metallographic 
vestigated by 
m electron and 
BM Was Used. 
m. The SEM ; 
DM Was carried 
eter Siemens 
‘gations were 
n. The surface 
€ 10 beam of 
Pt on the flat 
jae Fig. 1: OM images of different specimens of Al20Fe20Ni20Ti20V20 after heat treatment at 
oe a) 700 °C for 2h; b) 800 °C for 20 h; c) detail form b; d) 900 °C for 20 h; e) detail form d 
haps 3 45 SEM AND XRD INVESTIGATIONS 
oe nae First SEM results show a rather complex microstructure consisting of two main phases 
asphere. : (solid solution and coarse V-rich phase) and two other phases in only small volume 
ured Maer fractions (Cu- and Cu-Ti-rich phases), which may dissolve during a proper annealing 
treatment (Fig. 2a und Fig. 2b). In addition to the coarse V-rich phase, very fine particles 
can be seen in the matrix. Furthermore, regular precipitations are visible this coarse phase 
(Fig. 2c and 2d). Fig. 3 shows the EDS element mappings with V and Cu distribution which 
uniquely identify V- rich phase (Fig. 3b) as well as some isolated particle of Cu-rich phase 
(Fig. 3c). Moreover, it can be seen that near the coarse particles vanadium has been 
completely removed from the matrix. EDS results averaged over a large areas of the alloy