Ductile-to-Brittle Transition Temperature (DBTT)
Engineering definition, metallurgical mechanisms, standard testing specifications, and manufacturing guidelines for closed-die forgings up to 50 kg.
Quick AnswerFeatured
The critical temperature threshold below which a body-centered cubic (BCC) metal loses its plastic ductility and fractures in a sudden, brittle cleavage manner.
Technical Explanation & Metallurgical Principles
Body-centered cubic (BCC) steels (like carbon steels A105 and low-alloy steels) experience a sharp drop in impact energy as temperature drops. Austenitic stainless steels (FCC) do not exhibit a DBTT and remain ductile down to absolute zero.
Key Engineering Specifications & Parameters
| Technical Parameter / Metric | Engineering Benchmark / Value |
|---|---|
| ASTM A105 DBTT | Typically between -10°C and -29°C |
| ASTM A350 LF2 DBTT | Engineered below -46°C (-50°F) via fine-grain practice |
| SS 304L/316L DBTT | None (FCC lattice maintains ductility at -196°C) |
Application at Jayesh Forge (Rajkot Plant)
We produce ASTM A350 LF2 normalized forgings with aluminum-killed fine grain melting to guarantee low DBTT for arctic and LNG service.
Related Materials, Standards & Products
Related Metallurgical & Testing Terms
Charpy V-Notch Impact Test (CVN)
A standardized dynamic test that measures the kinetic energy absorbed by a notched 10x10mm specimen when fractured by a swinging pendulum hammer at specified temperatures.
Austenite (Gamma-Iron Phase)
The face-centered cubic (FCC) solid solution of carbon in gamma-iron, stable in unalloyed steels between 912°C and 1394°C, and stabilized at room temperature in 300-series stainless steels.
Ferrite (Alpha-Iron Phase)
The body-centered cubic (BCC) crystalline form of iron, stable at room temperature in unalloyed steels, exhibiting magnetic behavior and low carbon solubility.
Questions Regarding Ductile-to-Brittle Transition Temperature (DBTT)
Their face-centered cubic (FCC) crystal structure features 12 active slip systems that operate freely even at liquid nitrogen temperatures (-196°C).
Request a Forging Quote with Ductile-to-Brittle Transition Temperature (DBTT) Compliance
Our Rajkot metallurgy desk is ready to review your technical drawings, testing protocols, and delivery schedules for custom closed-die forgings strictly up to 50 kg.