Mechanical testing of weld metal

Date 11-21-2008 03:12

Just so I am understanding this question correctly, you're looking for the smallest size welding specimen that can be used for destructive testing Such as bend tests and tensile pulls?

Do you have any more information on the process or material as this varies somewhat by code and process.

By sazid98 (*)

Date 11-21-2008 03:21

Many thanks for your response. yes you are right i am looking for smallest recommended sizes of specimen for doing tensile and bend test (longitudinal & transverse ) on weld joint.

I will be doing steel and titanium mainly.

thank you again i will be waiting for your help

Regards

Sazid

By Metarinka (****)

Date 11-21-2008 03:32

Any particular material thickness you are doing? from personal experience the codes and tests used in the sheet metal industry (my field) are different from those of the structural material and again different from those used in jumbo sections or deep penetration processes like SAW.

I'll look into this tommorrow while I'm at work infront of code books, and I'm sure some other more experienced forum members have the answers too

By sazid98 (*)

Date 11-21-2008 03:40

I will joining two pieces together with a maximum thickness of a quarter of an inch.

again many thanks. i will be waiting to hear from you. if anyone have any information regarding this issue i will be very much thankful.

thank you

Regards

By 803056

Date 11-21-2008 04:29

If no specific welding standard is specified you can use AWS B2.1 for qualification requirements and B4.0 for mechanical testing.

Best regards - Al

By js55

Date 11-21-2008 14:27

Al is right, those are good standards. If nothing else is specified.
Also, if nothing else is specified there is no need to maintain your test coupon as the same thickness as your production coupon.
Or, if there is no specified standard all you need concern yourself with as far as tensiles are concnerned is making sure you have a enough linear dimension for thegrips in the tensile machine to grab it without interferring with the pull, and making sure you have a reduced section so that the pull happens where you want it to.
The thickness would be the thickness fo your material, the width would be standard, unless you have material limitation there as well.

By Metarinka (****)

Date 11-21-2008 20:15

Al and Js55 nailed it.
I would post a some of the figures from the qualification clause but I don't want to run afoul of AWS

for the record the minimum coupon width for bend tests would be 10 inches the minimum length would be 12" for material 1/16"+
That would be the overall coupon dimensions from which you would cut individual specimens. That gives area for the tabs plus enough room to cut several specimens with disposed area inbetween cuts.

for tensile pulls the reduced width section should not be less than width of weld +2 times the diameter of the section (if using turned specimens) and the threaded section would be approximately 7/8" for .25" material so the overal specimen length would be about 2.25"+ weld thickness.

I'm curious as to the need to minimize specimen size? Rare or exotic material?

By GRoberts (***)

Date 11-21-2008 23:53

The size of the specimen is dicated by the welding code governing the applications, such as ASME Section IX, AWS D1.9 (for Ti), B2.1 (as Al mentioned), etc. You can't generally pick a code based on the sample sizes you want. However, that is only if you are building something to the code. I see that you are from a university though, and could be perhaps just doing research? If that is the case, there isn't much difference between the AWS type codes structural codes. They generally require rectangular full thickness tensile tests. However, ASME allows turned specimens and has specimen sizes down to .188" diameter with a length of "the width of the weld plus 2D".

By sazid98 (*)

Date 11-23-2008 08:15

Many thanks to you all. i was looking into ASTM E8 also and found that one is rectangular tension test specimen and another one is pin loaded secimen. what is the difference between these two other than one is gripped by jaws and the later type is ficed in the tensile testing machine with a pin going through the hole made in the grip section.