$2012\_$ENSC$10..\mathrm{.}012.$pdfipdf

QUESTION $6$

$($a$)$ An annealed$-$steel specimen has a $0\mathrm{.}505$ in diameter $2\mathrm{.}0$ in gauge length. When subjected to a tensile force, the maximum load reached was $15,000lbs.$ and fracture of the specimen occurred at $10,000$ lbs$.$ For this steel, E is $30{10}^6$ Psi. Given this, answer the following:

$($i$)$ What is meant by annealed$-$steel?

$(3$ Marks$)$

$($ii$)$ Determine the ultimate tensile strength?

$(4$ Marks$)$

$($iii$)$ Why does fracture occur at a lower loid than the maximum load?

$(3$ Marks$)$

$($iv$)$ Determine the elongation of in ensile stress of $15,000$ Psi is appled?

$(4.$Marks$)$

$($b$)$ Corrosion is classified according to the manner in which it is manifest. For example galvanic corrosion occurs due to electrital coupling of two metals while exposed to an electrolyte. List six $(6)$ other forms of corrosion and explain the tochniques employed as general corrosion prevention methods.

$(6$ Marks$)$