A separate table indicates some of the grades that have been grouped together.
Steel Types (AISI) | Density | Modulus | Expansion | Conductivity | Specific Heat | Resistivity | |
. | . | 20oC | 400oC | . | . | . | . |
Ferritic stainless steels | |||||||
410S | 7700 | 220 | 195 | 10.5 | 30 | 460 | 0.60 |
430 | 7700 | 220 | 195 | 10.0 | 25 | 460 | 0.70 |
444 | 7700 | 220 | 195 | 10.4 | 23 | 430 | 0.8 |
Martensitic and precipitation hardening stainless steels | |||||||
410 | 7700 | 215 | 190 | 10.5 | 30 | 460 | 0.60 |
440 | 7700 | 215 | 190 | 10.4 | 15 | 430 | 0.8 |
630 | 7800 | 200 | 170 | 10.9 | 16 | 500 | 0.71 |
Austenitic stainless steels | |||||||
304 | 7900 | 200 | 172 | 16.0 | 15 | 500 | 0.73 |
316 | 8000 | 200 | 172 | 16.0 | 15 | 500 | 0.75 |
‘6%Mo’ | 8000 | 195 | 166 | 16.5 | 14 | 500 | 0.85 |
Duplex stainless steels | |||||||
‘2205’ | 7800 | 200 | N/A | 13.0 | 15 | 500 | 0.8 |
AISI | EN Grades Covered |
410S | 1.4000 |
430 | 1.4016 |
444 | 1.4521 |
410 | 1.4006, (410), 1.4005, (416), 1.4021, (420) |
440 | 1.4112, (440B), 1.4122, 1.4125, (440C) |
630 | 1.4542, (17/4 PH) |
304 | 1.4301, (304), 1.4305, (303), 1.4306, (304L), 1.4307, (304L), 1.4541, (321), 1.4550, (347) |
316 | 1.4401, (316), 1.4404, (316L) |
‘2205’ | 1.4462, (2205) |
‘6%Mo’ | 1.4547, (254SMO) |
‘Density’
The units are kg/m3 and are assumed to be for ambient temperature only.
‘Modulus’
This is the ‘elastic’ or ‘Young’s’ modulus. Sometimes expressed as ‘E’. Values at ‘ambient’ 20°C and 400°C only are shown. The units are kN/mm2
BS EN 10088-1 has values in 100-degree steps up to 300, 400 or 500°C, depending on the steel ‘family’ involved.
‘Expansion’
The thermal expansion figures shown are an average between 20°C and 100°C only. BS EN 10088-1 has values shown as averages between 20 and 100, 200,300,400 and 500 °C, depending on the steel ‘family’ involved.
The units are ‘ 10-6 x K-1 ‘. This represents the increase, (or decrease), in length that a 1 metre length of material will expand, (or contract), if the temperature is changed by 1 degree Kelvin, (which can be taken as 1 degree Centigrade for practical purposes).
So a value of ’10’ indicates that a 1 metre length of steel expands by 0.000010 metres, (0.010mm), if the temperature rises from 20 to 21 °C.
‘Conductivity’
The thermal conductivity values are for 20°C only. The units are W/m.K.
This represents the amount of heat, in watts, that is conducted by the material, where there is a temperature difference of 1-degree Kelvin. (This represents a one-metre cube of material, with a 1-degree temperature difference on opposite faces)
‘Specific Heat’
This is shown in BS EN 10088-1 as ‘Specific thermal capacity’ at 20°C. The units are J/kg.K, i.e. ‘Joules per kilogram x degrees K’
‘Resistivity’
The units of ‘electrical resistivity’ are ‘ohm.mm2/m’ and are shown at 20°C, as shown in BS EN 10088-1. These units are the same as ‘micro-ohm.m’.