After that the amount of the eutectic was measured at low magnification. The amount of Al,Cu 
and the pole phase was so calculated that the ratio of Al,Cu phase was multiplied by the measured amount of 
WC momo. eutectic. The average amount of the second phase was plotted against the three different constant 
solid/liquid interface velocities. These values can be seen in Fig. 4. 
2.2 
2.13 
Tr 
2.0 4-—— Bi 
X19 FF 
4 184 
a 17 
7 
i 1.6 + 
+ 
A LS x Af 
14 14 = 
1.3 1- 
12 + 
0.E+00 2.E-04 4.E-04 6.E-04 8.E-04 1.E-03 
| Solid/liquid interface velocity, m/s 
itely only at high 
tion, the analysis Fig. 4: Amount of the second phase vs. solid/liquid interface velocity 
ce the error im 
curacy at low 
enerated part of Determination of the primary, secondary and tertiary dendrite arm spacing 
2 second phase 
1 magnification For measurement of primary, secondary and tertiary dendrite arm spacing the polished sections of 
> analyser. The specimens were etched in 1% HF + water solution. 
zation operation Typical dendritic structures with the second phase of non-equilibrium eutectic are shown 
ell as the ALCu in Fig. 5. Influence of the cooling rate on the developed microstructure can be seen in Fig. 6. 
ted 10.34). The 
30pm | 100 pm | 
| Holes 4 
Fig. 5: Dendritic structures with the eutectic on the dendrite arm boundaries, v=2x10" m/s 
or ms 
31