Short answer: Quenched and tempered steel is a low-alloy plate hardened by rapid quench then tempered to combine high yield strength with good toughness, used in cranes and heavy structures, with the base in our Carbon Steel Supplier page and the heat treatment in our Heat Treatment Steel Guide.
At a Glance
What Quenched and Tempered Steel Is
QT steel is heated to austenite, quenched to form martensite, then tempered to regain toughness. The result is a high-strength plate (S355QL up to S960QL, A514) with good low-temperature impact. The heat treatment behind it is in our Heat Treatment Steel Guide.
Notes communes
S355QL suits general high-strength structures, S690QL serves crane booms and lifting gear, and A514 is common in North American heavy equipment. The comparison below lists typical yields.
| Grade | Yield | Use |
|---|---|---|
| S355QL | 355 MPa | Structures |
| S690QL | 690 MPa | Cranes |
| A514 | 690 MPa | Heavy equipment |
Soudage et fabrication
QT steel needs controlled heat input and often preheat to avoid softening the heat-affected zone; the rules are in our Metal Welding Guide and certified testing in our Third-Party Inspection Guide.
Where It Is Used
Typical duty is mobile cranes, bridges, mining frames and pressure parts, with the structural context in our Metal for Construction Guide and the transport view in our Metal for EV Guide.
Specifying and Sourcing
State grade, thickness, dimensions and any impact requirement; compare forms in our Steel Plate Buyers Guide, plan quantity with our MOQ and Lead Time Guide and price with our Price Quotation Guide.
Get a Quote
Tell HXSCO your requirements and we will respond with a competitive quote and lead time.
Questions fréquemment posées
Hardened by quenching then tempered for strength plus toughness.
S690QL roughly doubles the yield for lighter structures.
Yes but with controlled heat input and often preheat.
A North American high-strength QT grade near 690 MPa yield.
Give grade, thickness, size and impact temperature.
Source QT Steel
HXSCO supplies quenched and tempered plate S355QL, S690QL and A514 with impact testing. Send grade, thickness and quantity for a quote.