After to be made the micrograph, appeals manual it of metallography, in order to find the structure most similar of the micrograph, and through comparisons it is arrived determination of the micron-constituent. Description of the assay: The micrographs had been generated in an optic microscope, with the aid of the television that also reproduced the image seen for the microscope, using itself the objective lenses with magnifyings of 50x, 100x, 200x, 500x and 2500x. It is located part in the microscope and becomes the analyses. We can from the microscopical analysis, to determine and to identify the constituent of the texture of the analyzed steel. E, after the attack, also observes the ratios of the constituent, its dimensions, its abnormal distribution, structures and strange elements. Of the one to also have idea of the mechanical properties, in accordance with the constituent there gifts.
5? RESULTS AND QUARRELS to follow are presented the micrographs gotten in the material. With objective to analyze the structure and present texture in the steel after the attack with Nital 2%. Figure 12? Micrograph Steel SAE 1020 In agreement analysis in the microscope (figure 1) is possible to identify the contours of grains of the league, between a grain and another one meets the interstices where if it finds carbon, and different colorations that represent the structures of the steel in analysis, are they: Figure 13 – Cementita? Ferrite Iron Bubbles – Green: it indicates the presence of Cementita (Carboneto of Fe3C iron). – Brown: it indicates the Ferrite presence, composed for iron and baixssimo carbon text. – White: it indicates the presence of Iron. – Black: it indicates the presence of incrustation or bubbles (oxygen) that they are formed during the process of manufacture of the league. One also notices that in the micron-structure of the league it is possible to observe that the grains are all lined up, in the same direction and orientation.