Alphabetical Index
Chemical Composition
Keyword Search
AFNOR Steels
AISI/SAE Steels
BS Steels
DIN Steels
Wr.Nr. (Mat.No.) Steels
Calculated Diagrams
CCT Diagrams
TTA Diagrams
TTE Diagrams
TTT Diagrams
TTP Diagrams
TTS Diagrams
Alloy Steels
Carbon Steels
Carburizing Steels
Cast Irons
Chromium Steels
Cold Work Tool Steels
High Speed Steels
Hot Work Tool Steels
Low Carbon Steels
Microalloyed Steels
Molybdenum Steels
New Diagrams
Nitriding Steels
Plastic Mould Steels
PM Steels
Stainless Steels
Steel Companies
Structural Steels
Tools Steels
Vanadium Steels
Welding Steels
White Cast Irons
Help
Home
0.20C-0.28Si-1.25Mn-25 ppm B Steel
Steel name: 0.20C-0.28Si-1.25Mn-25 ppm B
Diagram No.: 5144
Type of diagram: CCT
Chemical composition in weight %: 0.20% C, 0.28% Si, 1.25% Mn, 0.015% P, 0.008% S, 0.15% Cr, 0.044% Al, 25 ppm B
Steel group: Boron steels, low alloyed steels
Note: Boron exerts a large influence on mechanical properties of steel through microstructural control. It increases the hardenability of steel by retarding the heterogeneous nucleation of ferrite at the austenite grain surfaces and the decomposition kinetics of austenite to ferrite transformation are governed by its location and chemical state. To understand the effect of boron (~ 25 ppm) on microstructural evolution and change in continuous cooling transformation (CCT) diagram , a systematic study has been carried out using Gleeble thermo-mechanical simulator in unalloyed (C: 0.05 wt%; Mn: 0.2 wt%) and low alloyed (C: 0.2 wt%; Mn: 1.2 wt%: Cr: 0.15 wt%) steels. CCT diagrams, plotted for the onset and end of pearlitic, bainitic and martensitic reactions, consisted essentially of two C-curves and a remarkable difference was observed on comparing the results for both steels. It is interesting to note that bainite and martensite are completely absent even at higher cooling rate of 70°C/sec in the unalloyed steel with boron addition. In contrast, the addition of boron was observed to promote significant bainite formation even at a slower cooling rate of only 20°C/sec in the low alloyed steel. These contradicting effects on hardenability can be explained by the effect of boron in shifting only the upper C curve to the right for reconstructive transformation.
Reference: Not shown in this demo version.
Transformation Diagram
Price: 20.00 US $
Buy Online Transformation Diagram
Other Steel Data links
Carbides in Steel
CCT and TTT Diagram Calculating Service
CCT and TTT Diagrams Home
Hardenability Diagrams of Steels
Hardenability Calculating Service
Macro Defects in Steel
Metal Etchants
Non-Metallic Inclusions in Steel
Tempering Diagrams of Steels
Semiconductor Etchants
Disclaimer: The information and data presented herein are typical or average values and are not a guarantee of maximum or minimum values. Applications specifically suggested for material described herein are made solely for the purpose of illustration to enable the reader to make his own evaluation and are not intended as warranties, either express or implied, of fitness for these or other puposes. There is no representation that the recipient of this literature will receive updated editions as the become available.