Effect of Manganese and silicon

[fakhmed]

Dear All,

As general for carbon steel (SA 516 Gr 70) what is the effect of high or low manganese and silicon on the steel behaviour ?

Thanks

 

[metengr]

The affect of alloying elements in carbon and low alloy steels is generally described below, and would apply for SA 515 Grade 70 steel;

http://www.key-to-steel.com/default.aspx?ID=CheckArticle&NM=10

http://www.key-to-steel.com/default.aspx?ID=CheckArticle&NM=50

 

[metengr]

One additional comment is that higher silicon content will reduce notch toughness behavior in carbon and low alloy steels, in general. However, for SA 515 Grade 70 steel, this is for moderate temperature service (coarse grain structure) and notch toughness is not really that important.

 

[Metalguy]

But it may be for the 516-70 in question.

"When the eagles are silent, the parrots begin to jabber."
Winston Churchill

 

[metengr]

Metalguy;
Yes, I agree with you, it will for the SA 516 Grade 70 steel plate. For some reason I had SA 515 in my small brain versus SA 516.

Jr/Sr moment

 

[stanweld]

For A-516 70, increasing Mn increase strength; higher Mn:C ratios benefit toughness at low temperatures. Metengr's comments regarding Si also apply to A-516.