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Re: [MW:12773] microstructure during arc welding

By Materials & Welding

Dear Antony

1 - Purpose of evaluating microstructure in mild steel is to understand weather some undesired phases produced during welding or not, however in mild steel producing such phases (such as martensite) is not a probable problem. The other purpose is to see how weld metal, HAZ and base metal arranged.

2 – As far we know, HAZ consist of three zones. The first is recrystallization part, the second is coarse grain zone and the third is fine grain zone. Each part is important in situ. For example unexpected growing of grains in recrystallization and coarse grain zones will affect impact properties of steel. Also dimension of these three parts is important.

3 – If carbon equivalent goes to increase, the presence probability of martensite will increase also. Some precautionary actions shall assist in welding, such as preheating.

 

Regards



On Tue, Oct 25, 2011 at 1:11 AM, Antony Jopen <antonyjopen@gmail.com> wrote:
Hi, 

Could someone throw some light on the the following topics:

1. Development of microstructure during arc welding of mild steel plate.
2. Changes which occur in the HAZ.
3. How would the structure change if the CE of the steel was increased.

Many thanks in advance.

--
Regards

Antony.

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--
M. Shokri Arfaei
International Welding Engineer (IWE)
ASNT NDT Level III
ERI Metallurgy Lab. Manager
Tel: +98-21-66283696
Fax: +98-21-66283693

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