Simulation test

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Name Surname Registration Number Part A 1) Why N effect in solution strengthening is higher than that of C? • Because N lattice distortion is lower • Because C increase cross sleep • Because N is more effective in lattice distortion and reduce cross slip 2) The Orowan process takes place if: • The precipitates can be cut by the dislocations moving through them • The dislocation can bypass the particle by changing its slip plane • If the particles are impenetrable by the dislocations 3) To increase pitting corrosion resitance the better solution is: • Increase Mo content • Decrease Cr content • Increase C content 4) Intergranular corrosion in stainless steel may be avoided: • Welding it • Solubilizing it • Immersing it in sea water 5) Duplex stainless steel: • Are martensitic • Have higher resistance to SSC than austenitic • Have lower mechanical properties than ferritic 6) How IF steels strengthening mechanism works? • Solute atoms replace atoms of the solvent material in the crystal lattice. Since the solute and solvent atoms are different sizes, they interrupt the regularity of the crystal lattice. Dislocations cannot easily move around this interruption. • Alloying elements exceeding the solubility limit within the steel lattice matrix segregate at the grain boundaries. The finer are these grain boundaries segregations, the higher will result the strengthening of the steel due to the induced grain refinement. • Solute atoms, replacing the atoms of the solvent material in the crystal lattice, act as dislocations source whenever a stress is applied. The high density of solute atoms within the lattice ensures a high dislocation density, consequently, the dislocations movements are hindered. 7) Which of these properties do NOT belong to DP steels? • High stretch…