Strength of Laser Weld before/after Heat Treatment 1

[huiying]

Hi,
I would like to know whether there is any difference in the weld strength if

a) welding without any heat treatment
b) welding after heat treatment
c) welding prior to heat treatment

and what's the reason?

Thanks & Regards.

 

[EdStainless]

What material are you welding?
It depends on the strengthening mechanism.

In general, (C) will give you the least variation in properties across the weld. This is considered the 'right' way to do it, but it may not be required.
You need to know more details before you can evaluate A & B.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[Goahead]

EdStainless' answer is correct.
However it is the question that is inappropriate.
You may have the case of solution treated and aged aluminum alloys sheets (2xxx and 7xxx) that can only be resistance welded after heat treatment.
So it is also a question of process, not only of material.

http://www.welding-advisers.com/

 

[huiying]

Hi,
Thanks for your replies. The material that that I'm welding is SS 17-4. I believe (C) will give the strongest weld. But how about comparing (A) and (B)? Which one do you think will give a stronger weld?

Thanks & Regards.

 

[metengr]

Here is a previous thread that you generated;

thread725-110139

From my brief review of information, for 17-4PH material you could possibly need to perform post weld heat treatment, depending on your design requirements. The things you do have going with the laser is no filler metal and it is a highly localized heat input.

 

[huiying]

What if heat treatment is carried out before welding. Is there any problem with that? Is the expected tensile strength of the weld expected to be lower than if the raw material is welded without any heat treatment?

 

[metengr]

huiying,
The web site below provides information on 17-4PH stainless steel. When you click on the web site, find the precipitation hardening stainless steels and search for 17-4PH. In most cases, it is desriable to weld in a solution heat treated condition (A) followed by

I would recommend you review this information to understand the various strength levels and heat treatment options. Your post is too open ended to provide any direction.

 

[metengr]

I hit the submit button before I was finished. Here is the web site;

http://www.aksteel.com/markets_products/stainless.asp

(there are other web sites for this material, as well).

For the best results, it is desirable to weld in Condition A and heat treat to the specified H condition.

I have used conventional welding techniques where the material was H1100 prior to welding, and after welding, we had performed a post weld heat treatment using the H1150M heat treatment.