Brittleness
A material is brittle if, when subjected to stress, it breaks without significant deformation (strain). Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a snapping sound. Many steels become brittle at low temperatures (see ductile-brittle transition temperature), depending on their composition and processing.
CROSS SECTION mm² |
MATERIAL | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
ALUMINIUM | MILD STEEL | COPPER | STAINLESS STEEL* | |||||||||
W/R MJ/W |
W/R MJ/W |
W/R MJ/W |
W/R MJ/W |
|||||||||
2.5 | 5.6 | 10 | 2.5 | 5.6 | 10 | 2.5 | 5.6 | 10 | 2.5 | 5.6 | 10 | |
4 | - | - | - | - | - | - | - | - | - | - | - | - |
10 | 564 | - | - | - | - | - | 169 | 542 | - | - | - | - |
16 | 146 | 454 | - | 1,120 | - | - | 56 | 143 | 309 | - | - | - |
25 | 52 | 132 | 283 | 211 | 913 | - | 22 | 51 | 98 | 940 | - | - |
50 | 12 | 28 | 52 | 37 | 96 | 211 | 5 | 12 | 22 | 190 | 460 | 940 |
100 | 3 | 7 | 12 | 9 | 20 | 37 | 1 | 3 | 5 | 45 | 100 | 190 |
Table 2 : Physical characteristics of typical materials used in LPS components
QUANTITY | MATERIAL | |||
---|---|---|---|---|
Aluminium | Mild Steel | Copper | Stainless Steel | |
ρο(Ωm) | 29 x 10-9 | 120 x 10-9 | 17,8 x 10-9 | 700 x 10-9 |
α(1/K) | 4,0 x 10-3 | 6,5 x 10-3 | 3,92 x 10-3 | 0,8 x 10-3 |
γ(kg/m³) | 2 700 | 7 700 | 8 920 | 8 000 |
θs(°C) | 658 | 1 530 | 1 080 | 1 500 |
C s (J/kg) | 397 x 103 | 272 x 103 | 209 x 103 | - |
Cw (J/kgK) | 908 | 469 | 385 | 500 |
*Austenitic non-magnetic