Ductile SiMo Iron
By increasing the Silicon and Molybdenum content of SG Iron, the heat resistance and strength at high temperatures is increased.
Physical properties depend on temperatures; typical values are detailed in the table below:
C=3.2-3.8%, Si=4.0-5.0%, S < 0.02%, Mg=0.03-0.07%, Mo=0.5-1.5%
| Temperature oC | Tensile Strength N/mm2 | 0.2% Proof Stress N/mm2 | Modulus of Elasticity N/m x 104 | Hardness BHN |
|---|---|---|---|---|
| 23 | 550 | 480 | 14.8 | (200-240) |
| 300 | 480 | 395 | 14 | |
| 500 | 350 | 270 | 12 | |
| 800 | 50 | 30 | 2.5 |
The main application for SiMo is in Automotive Exhaust and Turbocharger Systems, but it is suitable for any high temperature application where both strength and ductility are required.
Machineability is similar to that of EN-GJS-500-7.
Guideline Figures for Maximum Manifold and Exhaust Gas Temperatures
| Material Grade | Max. Manifold Temperature °C | Max. Exhaust Gas Temperature °C |
|---|---|---|
| EN-GJS-400-15 | 700 | 770 |
| EN-GJS-SiMo (0.5% Mo) | 750 | 820 |
| EN-GJS-SiMo (1.0% Mo) | 780 | 820 |
| EN-GJS-SiMoNi | 795 | 835 |
| Ni Resist D-5S | 870 | 950 |