MTEN$-7010$C Advanced Materials Techniques

HW Assignment #$1$

Please work by yourself, show all work for partial credit, write neatly or type and submit answers in order.

You are given an austenitic $316$ stainless steel metal circular band to characterize $($see

picture below$),$ with the following known processing history:

The steel started as an ingot of isotropic and completely uniform grain size. This ingot

was rolled at room temperature to form a plate of $1\mathrm{.}5$ cm thickness.

A $3\mathrm{.}5$ cm wide and $70$ cm long strip was cut from the plate with the length along the

rolling direction. Sectioning of the strip was by EDM and caused no measurable damage.

This strip was bent into a circular loop approximately $22\mathrm{.}5$ cm in diameter

The loop was welded together using a conventional fusion welding technique $($with a

filler rod of the same material$)$ along its outside curved surface, with a weld melt pool

width of $0\mathrm{.}5$ cm $.$ You may assume for simplicity that the weld was made instantaneously

$($any effects due to the speed the weld transversed specimen can be ignored$)$ and that the

differences in heat dissipation between the edge of the ring versus its center are

negligible. A helpful resource on welding microstructures has been uploaded with this

assignment.

Your task is to determine as efficiently as possible: What is the microstructure of the band,

and how did the weld affect the underlying microstructure?

For the rolled strip prior to bending:

a$)6pts-$ What do you expect the microstructure at this stage to look like?

Briefly describe the microstructure using both words and images.

$($Do not just paste an image in$,$ identify the most critical features in a writing to the

extent somebody would be able to understand if the images were removed$)$

b$)3pts-$ Identify and clearly label a set of the three most applicable principal axes.

$($There may be multiple valid naming conventions$).$

c$)9pts-$ List the three combinations of principal axes you've identified for the rolled

stage $($e$.$g$.$ A$1-$A$2,$ A$2-$A$3,$ A$1-$A$3).$ For each cross$-$section formed by a pair of these

axes identify: $***$ if the cross$-$section is possible to acquire, $***$ if the of position the cross$-$

section is taken at matters, and $***$ if it provides worthwhile information that cannot be

gained by the other sections $($should this section be prioritized$).$

$($if may be helpful to consider along which principal axes, if any, do you expect the

microstructure to have positional variations and the part's processing symmetry$)$

For the rolled strip after bending:

a$)6$ pts $-$ What do you expect the microstructure at this stage to look like?

Briefly describe the microstructure using both words and images.

b$)3pts-$ Identify and clearly label a set of the three most applicable principal axes.

c$)9pts-$ List the three combinations of principal axes you've identified for the rolled

stage $($e$.$g$.$ A$1-$A$2,$ A$2-$A$3,$ A$1-$A$3).$ For each cross$-$section formed by a pair of these

axes identify: diamond if the cross$-$section is possible to acquire $$ if the of position the cross$-$

For the rolled strip prior to bending:

a$)6pts-$ What do you expect the microstructure at this stage to look like?

Briefly describe the microstructure using both words and images.

$($Do not just paste an image in$,$ identify the most critical features in a writing to the

extent somebody would be able to understand if the images were removed$)$

b$)3pts-$ Identify and clearly label a set of the three most applicable principal axes.

$($There may be multiple valid naming conventions$).$

c$)9pts-$ List the three combinations of principal axes you've identified for the rolled

stage $($e$.$g$.$ A$1-$A$2,$ A$2-$A$3,$ A$1-$A$3).$ For each cross$-$section formed by a pair of these

axes identify: diamond if the cross$-$section is possible to acquire, if the of position the cross$-$

section is taken at matters, and $**$ if it provides worthwhile information that cannot be

gained by the other sections $($should this section be prioritized$).$

$($if may be helpful to consider along which principal axes, if any, do you expect the

microstructure to have positional variations and the part's processing symmetry$)$

For the rolled strip after bending:

a$)6$ pts $-$ What do you expect the microstructure at this stage to look like?

Briefly describe the microstructure using both words and images.

b$)3pts-$ Identify and clearly label a set of the three most applicable principal axes.

c$)9pts-$ List the three combinations of principal axes you've identified for the rolled

stage $($e$.$g$.$ A$1-$A$2,$ A$2-$A$3,$ A$1-$A$3).$ For