Dual-phase steels
Usage
Hot-rolled dual-phase steels are predominantly used in the manufacture of passenger car and commercial vehicle wheels (wheel discs). In order to reduce weight at the same time as increasing service life, maximum use is made of the typical properties of these materials, namely great forming and hardening potential at the same time as high strength and good weldability.
Salzgitter Flachstahl delivers steel grades DP550 and DP600 in accordance with the Stahl-Eisen-Werkstoffblatt’ (Iron and steel material sheet) 097-1.
Standards
| Grade | Material no. | DE | FK1) | |
| SEW 097 Part 1 | VDA239-100 | |||
| DP550 | - | - | D | |
| DP600 | 1.0936 | DD33X | HR330Y580T-DP | D |
Chemical composition in percent by weight [%] (Heat analysis)
| Grade | C | Si | Mn | P | S | N | Al | Cu + Cr1) + Ni |
| max. | max. | max. | max. | max. | max. | |||
| DP550 | 0.1 | 0.15 | 1.40 | 0.07 | 0.008 | 0.009 | 0.020 - 0.060 | 1.00 |
| DP600 | 0.1 | 0.15 | 1.40 | 0.07 | 0.008 | 0.009 | 0.020 - 0.060 | 1.00 |
Mechanical properties
| Grade | Yield point Rp0,2 | Tensile strength [%] | Min. total elongation [%] | Nominal thickness | Rollable width |
| MPa | MPa | LO = 5,65 √SO | mm | mm | |
| DP550 | 300 - 400 | 530 - 620 | 24 | 3.00 - 6.00 | 900 - 1,500 |
| DP600 | 330 - 470 | 580 - 670 | 24 | 3.00 - 6.00 | 900 - 1,500 |
Welding
Provided the general technical rules are observed, these steel grades are highly suitable for welding and can be welded both manually and using automatic equipment without pre-heating. In order to achieve the basic material’s general properties for welding seams, suitable welding additives must be used and the appropriate welding conditions selected. When determining the welding conditions, particular care should be taken to set an acceptable limit for the thermal input.
Condition of delivery, scope of testing and certificate
For delivery and testing, the provisions of SEW 097 apply. Other test units can be agreed.