Jan 22, 2013 · With the 2 1/4 % Cr and 1% Mo, P22 is a fairly deep hardening steel--far deeper than the same C level of a plain carbon steel. If it's flame/thermal cut cold, the surrounding metal will most probably pull heat away from the HAZ fast enough that martensite will form. Bainite Metallurgy for DummiesBainite is an acicular microstructure (not a phase) that forms in steels at temperatures from approximately 250-550°C (depending on alloy content). First described by E. S. Davenport and Edgar Bain, it is one of the decomposition products that may form when austenite (the face centered cubic crystal structure of iron) is cooled past a critical
The remaining portion is tempered martensite and has a first hardness. The cutting edge portion comprises a region that has been locally re-heat treated so that the microstructure in the cutting edge portion is untempered martensite having a hardness greater than the first hardness. Martensitic Stainless Steels Sandvik Materials TechnologyMartensitic Stainless Steels. Martensite, the hardest structural component in steels, is responsible for the high hardness in many sharp edge tools. The formation of martensite is a remarkable phenomenon in materials science and smiths have known for at least 3000 years how to make use of it to produce implements such as knives, axes and ploughs. Metallography of Steels - University of CambridgeMartensite transformation begins when austenite is cooled to a temperature below MSon the time-temperature-transformation diagram. It is a diffusionless transformation achieved by the deformation of the parent lattice into that of the product. Figure 22:Mechanism of martensitic transformation and the martensite-start temperature.
Jan 18, 2016 · And slower cooling rates are less likely to form martensite. Remember, high-carbon martensite is hard, strong, and brittle, and HAZ hardness is a function of the base metals carbon content. As the amount of carbon increases, so do hardness and the potential for cracking. At the same time, toughness decreases. Modeling of Martensite Transformation in White Layer under Nov 01, 2019 · Modeling of Martensite Transformation in White Layer under Thermo-mechanical Coupling in Hard-Cutting Process. Martensite volume fraction determines the hardness and wear resistance of workpiece, predicting the martensite volume fraction of the white layer is of great significance for improving the surface quality of the workpiece. Serrated Chips Formation in Micro Orthogonal Cutting of The high cutting force of martensitic alloy is because of the large yield stress required to overcome plastic deformation, and this force is also significantly affected by the orientations of the martensite.
Martensite is a very strong phase but it is normally very brittle so it is necessary to modify the mechanical properties by heat treatment in the range 150-700°C. Why Temper Through Hardened Steel - Industrial MetallurgistsTempering is used to improve toughness in steel that has been through hardened by heating it to form austenite and then quenching it to form martensite. During the tempering process the steel is heated to a temperature between 125 ° C (255 ° F) and 700 ° C (1,292 ° F). At these temperatures the martensite decomposes to form iron carbide particles.The Tempering of Martensite:Part OneThis process, which is called tempering, is one of the oldest heat treatments applied to steels although it is only in recent years that a detailed understanding of the phenomena involved has been reached. Essentially, martensite is a highly supersaturated solid solution of carbon in iron, which, during tempering, rejects carbon in the form of finely divided carbide phases.