Effects of temperature and oxygen concentration on decarburization of 55SiCr spring steel were investigated at the temperature range of 500°C–1 200°C by using a Muffle furnace (an atmosphere of ambient air) and a Simultaneous Thermal Analyzer (low oxygen concentration with 2% O2 and 98% N2). In ambient air, the decarburization behavior can be divided roughly into five temperature ranges: T≥1 20...

We have deposited a series of WC–Co coatings by the high velocity oxy fuel (HVOF) process, using three different powders, and different spray conditions. The powders are a nanocrystalline (Nanocarb), a near-nanostructured powder (Infralloy) containing a proprietary additive aimed at retarding grain growth, and multimodal (mixed micro and nano) powder (Nanomyte). HVOF spray conditions were stoic...

A. Volodarskaja, V. Vodárek, J. Holešinský, VŠB Technical University of Ostrava, FMME, Ostrava, Czech Republic. Š. Miklušová, O. Žáček. ArcelorMittal Frýdek-Místek, Frýdek-Místek, Czech Republic The final Goss texture in grain-oriented electrical steels (GOES) is affected by microstructure evolution and inheritance during the whole production process. This paper presents the results of detailed...

The Argon-Oxygen Decarburization (AOD) is the refining process of stainless steel to get its final chemical composition through several stages, where tons of materials are added and oxygen and inert gas are blown. The decarburization efficiency and the final temperature in each stage are two important values of this process. We present in this paper an empirical model, based on Multilayer Perce...

Adding high carbon ferromanganese in the early decarburization stage of 200 series stainless steel can reduce electrolytic manganese added during alloying; however, oxidation loss is severe. This paper studies CO2 and O2 mixed blowing thermodynamics kinetics on retention steel. The thermodynamic study indicates that reduces when used instead part molten decarburization. Meanwhile, kinetic deter...

Decarburization is a significant problem in the heat treatment of steels as decarburization is detrimental to wear life and fatigue life of components. This presentation concentrates on its measurement by four procedures. Test results from an interlaboratory test of steels with spheroidize annealed, lamellar pearlite (normalized) and quenched and tempered martensitic microstructures were evalua...

This paper presents the results of time and temperature resolved analysis of changes in phase composition and stresses/residual stresses during quenching and martensitic transformation of steel. Sample temperatures up to 900°C were reached with a specially-designed furnace, in which fast cooling of sample is executed by gas quenching. Stress development during quenching followed the expected tr...

A brief review of the high spatial resolution Auger electron spectroscopy (HRAES) and its usage in metallurgy is presented. A combination of HRAES and X-ray photoelectron spectroscopy makes a powerful combination to resolve a large number of problems encountered in metallurgy. Several selected examples of such problems studied in the authors’ laboratory are presented: influence of surface activ...