New developments with bainite have resulted in a steel with an ultimate tensile strength of 2500 MPa, a hardness of 600-670 HV and a toughness in excess of 30-40 MPa m [1]. The novel microstructure is generated in a high carbon (0.98 wt.%) high silicon (1.46 wt.%) steel austenitized for 15 min. at 1000 oC, and then isothermally transformed at temperatures of ∼200 oC. Iron does not diffuse durin...

the influence of aluminium on the microstructure of austempered ductile cast iron (adi) has been studied. the presence of well distributed graphite in the matrix, and a relatively high volume fraction of retained austenite are responsible for the good mechanical properties of the aluminium alloyed austempered ductile irons including excellent wear resistance, higher resistance to thermal shock,...

structural steels with very high strength levels are often referred to as ultrahigh-strength steels (uhss). the usage of uhss has been extensively studied in aerospace industries and offshore platforms. in this study, medium carbon low alloy steel (ams6305) was thermomechanicaly treated to obtain an ultra-high strength bainitic steel for aircraft engine compressor disk. a novel themomechanical ...

Low-temperature bainite, obtained by the transformation of austenite at temperatures as low as 200oC for times as large as several days, has been reported to have extraordinary mechanical properties including the highest reported hardness of any bainitic steel. The unusual properties are a consequence of the fine scale of the microstructure, which contains bainite plates with thickness in the r...

Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online's data policy on reuse of materials please consult the policies page. Abstract The effect of cobalt and aluminium on the austenite-to-pearlite transformation in a super-bainitic steel was investigated. The experimental work s...

In this work, three low-carbon bainitic steels, with different Mo contents, were designed to investigate the effects of Mo addition on microstructure and mechanical properties. Two-step cooling, i.e., initial accelerated cooling and subsequent slow cooling, was used to obtain the desired bainite microstructure. The results show that the product of strength and elongation first increases and the...

in this paper, effect of hydrogen diffusion on 2.25cr-1mo steel with ferritic-bainitic and martensitic microstructure has been investigated. hydrogen embrittlement of this steel was investigated by doing experimental such as delayed fracture and slow strain rate tests. result of this research was showed that the steel with martensitic  microstructure strongly affected by hydrogen diffusion and ...

bainitic transformation at low transformation temperatures leads to a microstructure involving fine plates of bainitic ferrite and thin films of retained austenite. this microstructure has shown ultimate tensile strength of about 2.2 gpa, noticeable uniform elongation in the range of 5 to 30%, hardness values of about 600 to 670 hv and impact toughness in the range of 30 to 40 mpa m1/2. with ca...

Structural steels with very high strength levels are often referred to as ultrahigh-strength steels (UHSS). The usage of UHSS has been extensively studied in aerospace industries and offshore platforms. In this study, medium carbon low alloy steel (AMS6305) was thermomechanicaly treated to obtain an ultra-high strength bainitic steel for aircraft engine compressor disk. A novel themomechanical ...

The microstructure characterization of tempered nanocrystalline bainitic steel is investigated in the present study. It is found that two types of plastic relaxation, dislocation debris and nanotwin, occurs in the displacive transformation due to relatively low transformation temperature and high carbon content. Because most carbon atoms trap in the dislocation, high dislocation density can be ...