High strength steels Q690+Q550 were welded using three different welding wires without preheating by gas shielded arc welding process. Microstructural characteristics of weld metals and nucleation mechanism of acicular ferrite were investigated by means of scanning electron microscope (SEM), energy dispersive spectrum (EDS) and transmission electron microscope (TEM). The straight Y-groove test ...

In situ three-dimensional (3-D) X-ray diffraction experiments have been performed at a synchrotron source on low-alloyed multiphase TRIP steels containing 0.25 wt.% Si and 0.44 wt.% Al and produced with different bainitic holding times, in order to assess the influence of the bainitic transformation on the thermal stability of individual austenite grains with respect to their martensitic transf...

Theoretical analysis has been carried out to establish the heat transport phenomenon of six different ferromagnetic MnZnFe2O4-C2H6O2 (manganese zinc ferrite-ethylene glycol), NiZnFe2O4-C2H6O2 (Nickel zinc ferrite-ethylene glycol), Fe2O4-C2H6O2 (magnetite ferrite-ethylene glycol), NiZnFe2O4-H2O (Nickel zinc ferrite-water), MnZnFe2O4-H2O (manganese zinc ferrite-water), and Fe2O4-H2O (magnetite fe...

The concept of a cyclotron-resonance maser (CRM) with a ferrite loading incorporated in its waveguide is proposed. The CRM interaction occurs between the rotating electron beam and the em wave propagating along a longitudinally magnetized ferrite medium. The ferrite anisotropic permeability resembles the CRM susceptibility in many aspects, and particularly in their similar response to the axial...

• Limited effect of temerping at 400 and 500°C on non-ausformed crabide-free bainite. Dilatometric contraction occurred for ausformed bainite sample due to cementite precipitation. Carbon diffusion was enhanced by dislocations generated during ausforming processes. The influence tempering 500 °C two bainitic ferrite microstructures obtained via pure isothermal transformation followed the studie...

Abstract Isothermal bainitic transformation of a lean medium-Mn steel containing (in mass%) 0.18C–3.6Mn–1.7Al–0.23Si–0.2Mo–0.04–Nb after full austenitization at 1100 ºC was studied by means high resolution dilatometry. The effects isothermal holding temperatures ranging from 450 to 350 °C on the kinetics experimentally characterizing microstructure present time 15 min 2 h. obtained results show...

The following nomenclature is used in this Chapter: a allotriomorphic ferrite aa acicular ferrite a w Widmanstatten ferrite ~ delta-ferrite !:i.0' increment in yield stress I austenite € true strain € true average strain €~ true plastic strain in softer phase of a dual-phase steel €~I true plastic strain in harder phase of a dual-phase steel €UTS true strain at ultimate tensile stress €y true s...

Phase transitions in CuAlMn alloys containing up to 12 at% Mn and 27 at% A1 continuously heated up to 5500C were studied using differential scanning calorimetry and transmission electron microscopy. Alloys containing less than 4.8 at% Mn exhibit an exothermal heat effect in the range 280 380°C due to y2 precipitation. The additional endothermal peak above 5000C is caused by DO3 disordering. All...

We report the synthesis and characterization of ferrite nanocrystals which exhibit high crystallinity and narrow size distributions. The three types of samples including Zn ferrite, Mn ferrite, and Mn-Zn ferrite were prepared via a non-aqueous nanoemulsion method. The structural, chemical, and magnetic properties of the nanocrystals are analyzed by transmission electron microscopy, X-ray diffra...