Stringers are filaments of

slag Slag is a by-product of smelting ( pyrometallurgical) ores and used metals. Broadly, it can be classified as ferrous (by-products of processing iron and steel), ferroalloy (by-product of ferroalloy production) or non-ferrous/ base metals (by ...

left in

wrought iron Wrought iron is an iron alloy with a very low carbon content (less than 0.08%) in contrast to that of cast iron (2.1% to 4%). It is a semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight), which give it a wood-like "grain" ...

after the production process. In their correct proportions their presence is beneficial, as they help to control the

ductility Ductility is a mechanical property commonly described as a material's amenability to drawing (e.g. into wire). In materials science, ductility is defined by the degree to which a material can sustain plastic deformation under tensile str ...

of the finished product, but when the proportion of slag is too high, or when the filaments run at right angles to the direction of tension, they can cause weakness.

Manufacture

Wrought iron is no longer made. The particles of slag present in the iron after preparation by

puddling A puddle is a small accumulation of liquid on a surface. Puddle or Puddles may also refer to: * Puddle, Cornwall, hamlet in England * ''Puddle'' (video game) * Puddle (M. C. Escher), a woodcut by M. C. Escher * Weld puddle, a crucial part of the ...

were drawn into long fibres during the forging or rolling process. The proportion of slag was intended to be about 3%, but the process was difficult to control and examples with up to 10% slag were produced.

Applications

Stays made from puddled iron bar were used as a cheaper alternative to

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish ...

for joining the inner and outer firebox plates of steam locomotives. The incorporated stringers gave flexibility akin to stranded wire rope and stays made of the material were therefore resistant to snapping in service. Wrought iron

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

s made from iron bar typically contained stringer filaments running the length of the rivet, but filaments at right angles to the tension, particularly beneath the head, caused weakness.

References

{{DEFAULTSORT:Stringer (Slag) Metallurgy Iron

Manufacture

Applications

See also

References