Castings of ASTM A494 CW6MC when Radiographed, it reveals random straight lines. Why?

[A M Contractor]

Recently I produced castings of the said grade. Melting done by Induction Furnace and Raw Material is Ingots made of INCONAL 625. All is good and castings are NSD in RT, but the films have revealed some dark lines in a particular geometry which is quite visible in all films. the client is asking a technical clarification as to why such line appear on the films?

 

[weldstan]

I'e seen these types of artifacts before. We looked at unexposed film and found the artifacts thereon.

 

[A M Contractor]

@weldstan
O I C. Here that is not the case. Your findings may be true and there must be some defective films but in my case I have tried it with multiple company films and results are same. So this rule out the possibility of defective unexposed films. Thank you

 

[Dhurjati Sen]

Can you carry out PAUT / Ultrasonic flaw detection of those sections?

DHURJATI SEN
Kolkata, India

 

[A M Contractor]

@Dhurjati Sen

This material is austenitic and UT will not work. Pls note that the lines observed in RT is not due to any physical presence but due to structure density and its variations. Even DPT does not show any discontinuity.

 

[JR97]

A.M.
It sound like diffraction. Very common in Inconel welds that we radiograph. Any way you take take photo of a film in front of a viewer and post?

JR97

 

[0707]

Can you have the possibility to use X ray machine? intead of gamma rays?