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2.5. Temperature development characteristics
The temperature development characteristics of a range
of stainless steel cross-sections with section factors Am/V
varying from around 200–700 m−1 were studied experimentally
[10], where Am is the surface area of the member per
unit length and V is the volume of themember per unit length.
Stainless steel has a lower specific heat than carbon steel (approximately
500 J/kg K compared to 600 J/kg K) which tends
to increase the rate of temperature development. It also has a
lower resultant emissivity than carbon steel, which tends to reduce
the rate of temperature development. The relative importance
of two effects has not yet been examined in detail, but
initial studies [6,18] have indicated that, for a given section factor,
the rate of temperature development in stainless steel sections
is lower than in carbon steel sections. The coefficient of
thermal expansion of austenitic stainless steel is approximately
50% larger than that of carbon steel, which may result in additional
loads being induced into structural elements due to restraint
from other (stiffer) parts of the structure. A detailed examination
of the results of the temperature development tests
and the effects of thermal expansion is currently underway.