Session: 03-13-02: Testing and Characterization

Paper Number: 161025

161025 - Precipitation Tailored Mechanical Behavior of Low Carbon Steels 

This study is concerned with examining the synergetic effects of co-precipitation of Mn, Ni, and Cu on quenched and tempered (Q&T) steels. Homogenised and forged steel blocks were subjected to Q&T treatments at 920℃ and 650℃, respectively to induce precipitation. Extensive study using scanning and transmission electron microscopy along with software simulation revealed the presence of (Ti, Cr)C and Cu-rich precipitates resulting in remarkably enhanced hardness and toughness of the steel. Precipitation evolution is studied with the help of MatCalc and Thermo-Calc simulation. Investigation using CCT curve simulated as a result of JMatPro envisage higher hardenability with increasing copper amount, which indicate substantial short-range diffusion, it could be resulting higher volume fraction of degenerate pearlite with increasing copper content as observed experimentally. A rich combination of strength, ductility and hardness i.e. 811MPa, 19.35% and 267±4 HV respectively has been observed after the tempering of 45 minutes along with remarkable tensile toughness of 146*10⁵KJ/m³. It is evident that improved toughness is combined effect of grain refinement due to the presence complex carbides and nano-size shearable copper precipitates. Effect of variation in copper content has also been investigated and reported in relation to toughness and hardness. Evolution and transformation Cu precipitates from the BCC (coherent) →9R (semi-coherent) →FCC (incoherent) crystal structures has been investigated vividly along with corresponding change in mechanical properties. In the due course mechanical behaviour as a result of microstructural variation is concluded with the help of fractography and misfit extent of copper precipitates.

Presenting Author: Kapil Dev Sharma Indian Institute of Technology Roorkee

Presenting Author Biography: I have dedicated the past more than 5 years to studying and researching various aspects of mechanical metallurgy. Currently, I am planning to defend my Ph.D. in “Role of Cu precipitation on the mechanical response of quenched and tempered (Q&T) steels” from the Indian Institute of Technology-Roorkee, India. Throughout my academic journey, I have developed a deep understanding of the fundamental principles of structure-property correlation, including simulation of various microstructural changes occurring during processing, and failure analysis. I have experience in the field of characterization, structure-property correlation and mechanical behavior of alloys. In my professional career, I have gained experience in characterization with APT, HR-TEM, SEM, EBSD, XRD, EDM, DSC, Optical profilometry, Hardness, UTM, Tribometer, forging press, Rolling mill, and Twinjet electropolisher. I have experience in working with software tools such as Thermo-Calc, MatCalc, TSL-OIM, Gwyddion, Gatan digital micrograph, X-pert high score, eSpot, ImageJ, MS Office, and Origin 9. I have successfully guided two intern students. After MTech., I worked as Assistant Prof. for a year, where, my responsibilities were to take classes, tutorials, labs and conducting exams.
I am always open to learn new things. Currently I am exploring machine learning techniques using various libraries of Python. I am always ready to take new challenges to learn new things. I am very much interested in additive manufacturing also due to its competitive advantages over the currents manufacturing and processing techniques.