Initiation of corrosion on reinforcing bars occurs when a critical chloride concentration is achieved. A universal value for the chloride concentration that causes depassivation has not been agreed upon for carbon steels due to a variety of experimental factors. The chloride threshold depends on the rebar material, rebar surface condition, testing environment, method of detection, definition of...

In this work, tensile and yield stress and tensile and yield strain of oblique layer functionally graded steels produced by electroslag remelting were investigated. Functionally graded steels containing ferrite, austenite, bainite, and/or martensite layers may be fabricated via diffusion of alloying elements during the remelting stage. Tensile and yield stress and tensile and yield strain of fu...

The elastic-plastic fracture toughness JIc tests by the stretched zone method were performed to obtain JIc values for machine structural steels. The validity of the JIc values obtained was evaluated, and the effects of the heat treatment conditions and microstructure of steels on the JIc values were investigated by use of streched zone width, SZW. The results obtained are summarized as follows....

SEM in-situ investigations of the micromechanisms of damage initiation and fracture in tool steels are described. The critical state of the material and the damage growth were observed in the tests. It was shown that the initial microcracks in the steels are formed in primary carbides and then join together. A hierarchical finite element model of damage initiation, which included a macroscopic ...

We have performed in situ synchrotron X-ray diffraction experiments to assess the influence of aluminium and phosphorus on the austenite stability in low-alloyed transformation-induced plasticity steels during the high-temperature bainitic holding and the subsequent martensitic transformation during cooling to temperatures between room temperature and 100 K. Although the addition of aluminium i...

The possibility of producing bainite at low temperatures by suppressing transformation using substitutional solutes has been investigated, as an alternative to using large carbon concentrations to achieve the same purpose. It is found that although transformation temperatures can indeed be suppressed in this way, the difference between the bainite and martensite start temperatures diminishes. T...

The toughness of martensitic steels is strongly related to their fine and complex morphologies. To control the steels, effect carbon content on morphology lath martensite must be studied. However, these morphological changes are difficult clarify using conventional two-dimensional observations because morphologies tangled. Previously, we analysed reported three-dimensional microstructures ultra...

Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe-Al-Mn-C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structu...

High-strength-low-alloy reinforcement bar steels prepared by vanadium microalloying methods have the potential to dramatically reduce embodied energy and carbon footprint of buildings.