Question

1. Which of the following stainless steels are tougher (better resistance against impact), Ferretic Stainless steel or Austenitic Stainless steel? Explain why?

    

                                                                                                                                   

                                                                                                                                   

                                                                                                                                   

2. Explain how the amount of cross linking controls the hardness in an polymer:

                                                                                                                                   

                                                                                                                                   

                                                                                                                                   

3. Titanium has HCP structure, is it electrically conductive? Explain your answer

                                                                                                                                   

                                                                                                                                   

4. Are stainless steels quench hardnable? Explain your answer:

                                                                                                                                   

                                                                                                                                   

Answer 1

The Austenitic stainless steels are tougher than ferritic stainless steel because Austenitic grades work-harden to a greater extent than the ferritic grades , so the rollover section of cut egde is higher strength.

Crosslinking serves the purpose of increasing molecular weight and the strength of a polymer is dependent upon the molecular weight as the molecular weight increases the strength increases. This is how the hardness is controlled by the cross linking of the polymer.

Titanium is not a good conductor of electricity. If the conductivity of copper is considered to be 100%, titanium would have a conductivity of 3.1%. Titanium forms a very thin oxide layer in air, which makes it resistant to corrosion but it also insulates the titanium.

stainless steels are not hardened by quenching. The only heat treatment applied to ferritic is annealing because they develop minimum hardness and maximum ductility, impact toughness and corrosion resistance in the annealed and quenched condition. Annealing also relieves stresses developed during welding or cold working and provides a more homogeneous microstructure.