Page 274 - Fiber Fracture

FRACTURE OF SUPERFINE METALLIC WIRES 257

(a)6pass(+5.8 mm-45.5 mm)
-g 200
z 5:
a
v
b
jtj 100 ?!
*P 30 ..I
M
20 9
1
2 10 O
0 OT
0 100 200 300 400
Drawing length(mm)

(c) 8 pass (45.1 mm-44.8 mm)

P -7

Fig. 18. AE signal and drawing stress during clad wiredrawing (a = 20").

(Fig. 22). The surfaces of both Cu and NbTi contained many dimples. Furthermore, the
interfacial adhesive condition between Cu and NbTi was relatively good.
The number of broken filaments among approximately 300 filaments was only 1
to 6 in the Cu-NbTi multifilament superconducting wire during the drawing process,