Development of Fe-11Al-xMN alloy steel on cryogenic temperatures

Abstract

This research is focused on increasing the reliability of Fe-11Al-Mn by combining the properties of Mn and the superiority of Fe-Al-C under cryogenic temperature. Three Fe-11Al-Mn alloys with compositions of 15 wt % Mn (F15), 20 wt % Mn (F20), and 25 wt % Mn (F25) were investigated. The cryogenic process uses liquid nitrogen in a temperature range of 0–196 °C. Hardness testing using the Vickers method and SEM was used to analyze the microstructure. X-ray diffraction (XRD) testing was conducted to ensure the Fe-11Al-Mn alloy phase and corrosion testing was carried out using the three-electrode cell polarization method. With the addition of Mn, the Vickers hardness of the Fe-11Al-Mn alloy decreased from 331.50 VHN at 15 wt % to 297.91 VHN at 25 wt %. The value of tensile strength and fracture elongation values were 742.21 MPa, 35.3 % EI; 789.03 MPa, 41.2 % EI; and 894.42 MPa, 50.2 % EI, for F15, F20, and F25, respectively. An important factor for improving the performance of cryogenic materials is the impact mechanism. The resulting impact toughness increased by 2.85 J/mm2 to 3.30 J/mm2 for F.15 and F25, respectively. The addition of the element Mn increases the corrosion resistance of the Fe-11Al-Mn alloy. The lowest corrosion rate occurs at 25 % wt Mn to 0.016 mm/year. Based on the results, the F25 alloy has the highest mechanical and corrosion resistance of the three types of alloys equivalent to SS 304 stainless steel. The microstructure of Fe-11Al-Mn alloy was similar between before and after cryogenic temperature treatment, this condition showed that the microstructure did not change during the process. From the overall results, the Fa-11Al-Mn alloy is a promising candidate for material applications working at cryogenic temperatures by optimizing the Mn content

Development of Fe-13.8Cr-8.9Mn alloy for steel biomaterials

“…It indicates that the S phase is the zone of nitrogen atom diffusion in the plasma nitriding of Fe-13.8Cr-8.9Mn alloy without an intrinsic interface. N atoms in the interstitial ɣ-Fe of the Fe-13.8Cr-8.9Mn alloy are soluble due to elemental Mn, as discovered by both researchers [30,53].…”

Comparative analysis of methods for calculating the physico-mechanical characteristics of multi-layered composite materials

“…The mechanical properties of composites are influenced by such factors as characteristics, type (fiber, fabric, etc.) and the volume content of the reinforcements, orientation of fibers (layup), as well as the characteristics of the resin and the contact zone [3][4][5]. Experimental determination of the mechanical characteristics of PCM for the large number of structural variants is extremely time consuming and costly, therefore, computational and theoretical methods have now come to important [6][7][8].…”