Page 260 - Fiber Fracture

FRACTURE OF SUPERFINE METALLIC WIRES 243

INTRODUCTION

Wiredrawing has a long history. In the past, wiredrawing, which was a significant
processing technique, was kept secret; consequently, there are few reports giving detailed
explanations of the technique. At present, the Deutsches Museum in Munich exhibits dies
and pictures which illustrate the wiredrawing operation since the 15th century (Fig. 1)
as well as Japanese pictures which illustrate the wiredrawing operation (Fig. 2; Naka-
mura and Wada, 1980), providing us some information on the wiredrawing environment.
Wiredrawing has shifted from being powered by man, to oxen or horses, waterwheels and
finally electric motors, resulting in great strides in productivity.
Recently, the application of the wiredrawing technique for superfine wires has
predominantly been in the fields of precision equipment, semiconductors and printing
machines. This is because new products with enhanced functions, including light, thin,
short and small wearable equipment, have been developed at the request of wire users,
and wire suppliers are reaping the benefits of an expanded market and increased value of
their wires. However, various problems, such as the extremely high manufacturing cost
of superfine wires, remain unsolved. Until now, the techniques and knowledge in this
field have been considered to be corporate know-how. Therefore, few papers or reports
on the wiredrawing technique have been published.

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Fq 1. Wiredrawing operation and an old die rn 15th century (Deutsches Museum in Munich)