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| Category | Type | Steel grade | Standard | Country |
|---|---|---|---|---|
| Grades | Special Alloy | K640 | GBT | China |
Chemical composition%of the ladle analysis of gradeK640
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | Ni(％) | W(%) | Co(%) |
|---|---|---|---|---|---|---|---|---|
| 0.45-0.55 | Max 1 | Max 1 | Max 0.04 | Max 0.04 | 24.5-26.5 | 9.50-11.5 | 7.00-8.00 | Balance |
| Proof strength Rp0.2(MPa) | Tensile strength Rm(MPa) | Impact energy KV(J) | Elongation at fracture A(%) | Reduction in cross section on fracture Z(%) | As-Heat-Treated Condition | Brinell hardness(HBW) |
|---|---|---|---|---|---|---|
| 872(≥) | 521(≥) | 33 | 24 | 23 | Solution and Aging,Annealing,Ausaging,Q+T,etc | 214 |
| Property | Density kg/dm3 | Temperature T °C/F | Specific heat J/kgK | Thermal conductivity W/mK | Electric resistance µΩ·cm | Modulus of elasticity kN/mm2 | Expansion rate |
|---|---|---|---|---|---|---|---|
| 724(≥) | 643(≥) | 14 | 32 | 33 | Solution and Aging,Annealing,Ausaging,Q+T,etc | 332 | |
| Temp. °C/°F | Creep strain limit (10000h) (Rp1,0)N/mm2 | Creep rupture strength (10000h) (Rp1,0)N/mm2 | |||||
| 342 | 773 | 561 |
| Product type | Products | Dimension | Processes | Deliver Status |
|---|---|---|---|---|
| Plates/Sheets | Plates/Sheets | 0.08-200mm(T)*W*L | Forging,hot rolling and cold rolling | Annealed,Solution and Aging,Q+T,ACID-WASHED,Shot Blasting |
| Steel Bar | Round Bar,Flat Bar,Square Bar | Φ8-1200mm*L | Forging,hot rolling and cold rolling,Cast | Black,Rough Turning,Shot Blasting, |
| Coil/Strip | Steel Coil/Steel Strip | 0.03-16.0x1200mm | Cold-Rolled&Hot-Rolled | Annealed,Solution and Aging,Q+T,ACID-WASHED,Shot Blasting |
| Pipes/Tubes | Seamless Pipes/Tubes,Welded Pipes/Tubes | OD:6-219mm x WT:0.5-20.0mm | Hot extrusion,Cold Drawn,Welded | Annealed,Solution and Aging,Q+T,ACID-WASHED |