Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

How do you become a picture like this?

Status
Not open for further replies.
Replies continue below

Recommended for you

Is this a riddle?
What is the material?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
Some type of stress corrosion cracking or hydrogen embrittlement.
 
I formulated the question the wrong way. Sorry.
I meant that I also want to take such pictures for my samples.
I have a camera nikon d5200,
a picture with colors makes it difficult to identify a break.

Thank you
 
You take these with a microscope.
Many scopes have ways to mount regular cameras, you just need to set the camera to grey tone only.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
Thank you for your useful answers
I have searched for an answer for a long time
that saves my samples next week.
thank you
 
The usual process is to cut the section that you desire to look at.
Rough cut with a band saw.
Then the sample in mounted either in thermoset (Bakelite) or a resin.
The face of the mounted sample is them polished.
You wet grind/polish in steps starting at 180 grit and working through 0.05 micron.
Then you often etch to reveal details of the structure.
Metallography is a science unto itself

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
Something I learned the hard way 54 years ago, Do it all by hand , do not be tempted to take a few passes on a surface grinder to speed things up.
You will end up with something that looks like a heat treated surface.
B.E.

You are judged not by what you know, but by what you can do.
 
The art of polishing using hand is dead. It is allautomption. Please recall Sir H.Morrogh who was a metallographer and polished several cast iron samples. One day while polishing he stumbled upon round graphite instead of flakes. His curiosity was aroused and thus BCIRA announced S.G Irons with spheroidal graphite.

Sorry for this digression I could not control myself. Thanks for your patience.

"Even,if you are a minority of one, truth is the truth."

Mahatma Gandhi.
 
People send me mounted samples to look at, I take a couple of photos as they sent them and then re-polish by hand.
I know a machine system can do 12 samples in the time that it takes me to do 1, but mine come out clear and free from artifacts.
And I don't do many.
And don't get me started on lighting methods and etching. It also seams that using polarized light or DIC has become passe.
I have two reference books on color etching, but getting some of the chemicals has become difficult.
I recently had a chance to use a confocal microscope for some macro work (2x to 20x). The depth of field was great, similar to SEM but a lot easier and less expensive.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
 
Capturing good quality photographs with a stereomicroscope can be difficult, especially when the surface is not flat (or worse, when it is flat and highly reflective).
You will be surprised what you can capture with a mid-range digital camera. The trick to taking macro pictures is to use minimum zoom, holding the lens close to the subject. The camera will tell you the minimum focal distance. The main tradeoff is distortion. If the area of interest is much smaller than the picture size, snap it at a high resolution setting and crop it using good editing software such as Gimp (it's open source).

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor