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In the present work we study the static indentation, i.e., the formation of small dents which result from laboratory tests specifically developed with this purpose. A mathematical model will be presented. It is based on the numerical and experimental tests performed with previous adjustment of all the mechanical variables involved. This model considers the test specimen and indentator geometry, the sheet anisotropic condition, the sheet's plasticity, and the contact conditions between the plate and the indentator developed. There is a goal to satisfy: specific requirements of a consumer market which is continuously willing for the development of materials with thinner thickness and better mechanical properties. To reach this goal, high strength steels manufactured by the SCAL (Sheet Continuous Annealing Line) are already been produced and tested in experimental scale. These bake-hardening steels can be used to manufacture external panels in the automobile industry.

Search for alloys with improved high temperature specific strength and creep resistance properties for aerospace applications has led in the last decades to sustained research activities to develop new alloys and/or improve existing ones. The maraging steels evoked tremendous interest, especially in the aerospace world. Extra low carbon, high nickel, iron based alloys held great promise of providing an extraordinary combination of structural strength and fracture toughness. Applications of this alloy include aircraft structural components and rocket engine case for Satellite Launcher Vehicles. The objective of this work is to study the creep behavior of a solution treated Maraging 300 alloy. Constant load creep tests were conducted with this alloy at 550°C and in a stress range of 200 to 500 MPa. The creep parameters are determined. Samples with a gage length of 18.5 mm and a diameter of 3.0 mm were used for all tests.

In this work five methods of heat treatments are investigated in order to obtained convenient volume fractions of ferrite, bainite, martensite and retained austenite, starting with a low carbon steel and seeking the distinction of the phases, through optical microscopy. Specific chemical etching is improved. The results in tensile and fatigue tests were accomplished and the results were related with the microstructural parameters. The results show that the mechanical properties are closely related with the phases, grains size and the phases morphology.