×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

fracture toughness evaluation from impact testing

fracture toughness evaluation from impact testing

fracture toughness evaluation from impact testing

(OP)
Hi,
I have conducted impact testing on my NbSi alloy at RT which is very brittle. What could be the relevant formula to evaluate the fracture toughness (stress intensity factor) of the material? I have few relations to calculate stress intensity factors but it's not clearly explained it can be used for brittle material as well. What other properties can be evaluated from the available data from the impact testing.
thank you
Vinston

RE: fracture toughness evaluation from impact testing

Vinston,

try cross posting to the nuclear engineering fourm, nukes are BF gurus. I used to know those equations but they have long been flushed from my memory.

Scott Peterson
Training Manager
Power Plus Engineering
www.epowerplus.com

RE: fracture toughness evaluation from impact testing

vinston;
There are no direct correlations between impact energy values and fracture toughness (KIc) for metals. There have been conversion formulas that are used for the upper shelf impact energy conversion of CVN to KIc for certain steels but again these are only used as approximate conversions and must be used with caution.

RE: fracture toughness evaluation from impact testing

(OP)
thanks for the input metengr, ZOgzog I posted it in the Nuclear forum..

RE: fracture toughness evaluation from impact testing

Vinston,

Impact testing will only provide some useful information if it is instrumented to collect force vs. displacement data.  A typical Charpy impact test that only provides the final energy absorbed will not provide any information on the fracture toughness, especially for a brittle intermetallic like NbSi.  You need to perform real fracture toughness testing according to a standard like ASTM E 1820.

RE: fracture toughness evaluation from impact testing

Charpy V-notch test? You are bring back brain cells I though died years ago. I used to love materials testing but havent used it in 20 years. You get a star!

RE: fracture toughness evaluation from impact testing

(OP)
TVP,
yes the test was conducted to get force vs Displacement data.I have the max force (load) before fracture and diplacement values. I remember for plastic material we can evalutae the energy absorbed by the specimen before fracture by integrating the area under the curve but how about the energy in case for brittle material where you get a single peak? I am gonna do 3pt Bending test as well to determine the fracture toughness but I want to compare the both values.
thanks
vinston

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close