×
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

Brittle Fracture on Tensile Ti GR12

Brittle Fracture on Tensile Ti GR12

Brittle Fracture on Tensile Ti GR12

(OP)

In reviewing a PQR, I notice one of the two tensile tests is reported to have a brittle fracture in the weld metal, both fail in the weld metal. Min tensile stress for this material is 485 MPa the tests results are 650 and 696 MPa (the brittle one). Both side bends are reported as being ok. No hardness tests have been carried out.

My question, is one brittle break in a tensile grounds to reject the weld test coupon? I have read through QW-150 and it is not addressed. I am learning towards yes as clearly a brittle micro structure is not a desirable material property for my application.

RE: Brittle Fracture on Tensile Ti GR12

You performed tensile and bend testing in accordance with ASME Section IX. The tensile strength of the weld exceeded the strength of the base metals and the bend tests passed, that is all you need for qualification. The successful bend tests demonstrate the weld region can accept up to 22% fiber tensile strain with no cracks or tears. I doubt you have brittle fracture. Grade 12 is a highly weldable alloy. The properties sheet I have shows a minimum of 18% elongation and 25% RA at RT.

RE: Brittle Fracture on Tensile Ti GR12

Meeting the minimum specified ultimate tensile strength of the base metals joined is all that is required along with location of failure. Fracture appearance is not germane to the test per ASME IX. Ductility is determined through the bend test. Often times fracture appearance is misinterpreted by the test lab (from personal experience).

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