×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Grain boundaries

Grain boundaries

Grain boundaries

(OP)
Hello all,
After grinding a 12" 25/20 centrifugal casting to a 10 Ra, the surface appearance of this tube looks uneven in color(light and dark areas). It has been explained to me that this is a reflection of the grain boundaries? Is this true because of the steel mixture being less homogeneous.

Thank you in advance for your answers.
Doug

RE: Grain boundaries

Is it a copper base alloy?

_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year

RE: Grain boundaries

Grain orientation, not their boundaries.

"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein

RE: Grain boundaries

When I look in ASM, micrographical section, for X15CrNiSi25-20 cast Stainless Steel, there are different colors/shades of the grains.

RE: Grain boundaries

You may also have removed different amounts of stock, the material near the surface may have different grain size/orientation that gives it a different look.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

RE: Grain boundaries

Ed is correct, a thin surface layer found in these castings will give a different colour when machined if the amount of stock removed is not uniform.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources