STEEL - Materials for Civil and Construction Engineers - page 120

FIGURE 3.18 Charpy V notch

specimens.

FIGURE 3.19 Charpy V notch im-
pact testing machine.

the energy required to fracture the specimen is computed. This energy is
measured in as indicated on a gauge attached to the machine.
The lateral expansion of the specimen is typically measured after the
test using a dial gauge device. The lateral expansion is a measure of the plas-
tic deformation during the test. The higher the toughness of the steel, the
larger the lateral expansion.
Figure 1.13, in Chapter 1, shows the typical energy (toughness) required
to fracture structural steel specimens at different temperatures. The figure

m # N ft # lb 1 2