• OSMAN AHMED

This study investigates the microstructure and mechanical properties of EN19 and EN353 steels subjected to quenching in different mediums. EN19 (AISI 4140) is a chromium-molybdenum alloy steel known for its high strength and toughness, while EN353 is a case-hardening steel widely used for components requiring enhanced surface hardness. The EN19 and EN353 steel alloy finds its application in the automotive industry like manufacturing gears, spindles, and shafts. In this investigation, we aim to improve the strength and ductility of the EN19 and EN353 steel alloy by quenching process. Generally, heat treatment is the method of exposing the specimen to high temperatures and cooling it, to bring a change in its physical and chemical properties. In this experiment, the process of quenching through different mediums were performed on the steel specimens. On heating the specimens to around 900⁰C, and cooling it from slower to a faster rate. On studying the microstructures and grain analysis of the specimens, we were able to observe the difference in the composition of the constituents and understand how this affects the mechanical properties of the material. The quenchants used are oil, air and water. The primary objective of this research is to analyze the effects of various quenching mediums—such as water, oil, and air—on the phase transformations, microstructure, and resulting mechanical properties, including hardness, tensile strength and impact toughness. Metallographic techniques are used to examine the microstructural changes post-quenching, while mechanical testing evaluates the performance of the quenched steels. The study reveals that the choice of quenching medium significantly influences the cooling rate, resulting in varied martensitic structures and grain refinement. These microstructural changes have a direct impact on the mechanical behavior of both EN19 and EN353 steels, providing valuable insights into optimizing heat treatment processes for specific engineering applications.

EN19 steel alloy, EN353 steel alloy heat treating, tensile strength, microstructure, hardness.

"AN EXPERIMENTAL INVESTIGATION ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF HEAT TREATED EN353 AND EN19 STEEL", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.12, Issue 1, page no.b7-b15, January-2025, Available :http://www.jetir.org/papers/JETIR2501127.pdf

"AN EXPERIMENTAL INVESTIGATION ON MECHANICAL PROPERTIES AND MICROSTRUCTURE OF HEAT TREATED EN353 AND EN19 STEEL", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.12, Issue 1, page no. ppb7-b15, January-2025, Available at : http://www.jetir.org/papers/JETIR2501127.pdf