Composition of AISI 10B21

[Bainite 1]

"Franc Koljaka" <annief...@iol.it> wrote Mon, 9 Jun 1997 20:42:53
+0200:

>>Hamish Hawthorn ha scritto nell'articolo
>><5n5n6o$srk$1...@snews2.magna.com.au>

>>Can anyone give me the chemical composition of AISI 10B21 steel?
>>Also, if anyone knows typical mechanical properties for this steel.

>>Regards,

>>Hamish Hawthorn
>>ham...@simmonswheel.com.au

>Hello.

>AISI 10B21 is one of 3 subgrades (A,B,C) of 1021
>(changes the % of Si and the shape : bars, rods or other).
>Subgrade A is for bars, B for drawn wire or rod and
>C for other shapes and the % of Si changes referring to
>diameter or thickness.

>Chemical composition :
>C%=0.18-0.23 Mn%=0.60-0.90 P%<=0.040 S%<=0.050%
>As for Si the possible contents are :
><=0.10%, 0.07-0.15%, 0.10-0.20%, 0.15-0.35%, 0.20-0.40%, 0.30-0.60%

>Mechanical properties :
>Diameter (mm) 0 - 16 17 - 40 41 -100
>Yield str. Re (>=N/mm2) 390 345 295
>Tensile str. Rm (N/mm2) 540-690 490-640 490-590
>Elong. A5 (>=%) 22 20 18
>Area red. Z (>=%) 50 55 60
>Impact val. Av (DVM) (J) 69 69 76

>Regards, Franc Koljaka - Italy.
>annief...@usa.net

Perhaps others in the newsgroup can offer their thoughts on this. I was
not aware that the " B " designation applied to one of three available
subgrades. It is my understanding that AISI 10B21 is a low carbon steel of
the composition mentioned, that contains between 0.0005 and 0.003 wt. %
boron. Boron is typically added to improve toughness at high strength
levels. The silicon content can vary. Mechanical properties for 10B21
will depend on the heat treated condition ( hot rolled, annealed, cold
finished, quenched & tempered ).

Regards,

Greg Dexter

[Franc Koljaka]

Greg Dexter wrote :

>
>Perhaps others in the newsgroup can offer their thoughts on this. I was
>not aware that the " B " designation applied to one of three available
>subgrades. It is my understanding that AISI 10B21 is a low carbon steel
of
>the composition mentioned, that contains between 0.0005 and 0.003 wt. %
>boron. Boron is typically added to improve toughness at high strength
>levels. The silicon content can vary. Mechanical properties for 10B21
>will depend on the heat treated condition ( hot rolled, annealed, cold
>finished, quenched & tempered ).
>
>Regards,
>
>Greg Dexter
>

Hello, Greg

You are absolutely right about the composition of AISI 10B21 steel. The
letter B indicates
that there is boron in the content of 0.0005-0.003 % and I have have
misinterpreted the
letters a, b and c for the silicon content (my source is "Stahlschluessel"
- Key to steel).
The mechanical properties I have given are for the AISI 1021 in quenched
and tempered
condition, but I believe that are approx. the same for the 10B21 grade.
I will be more careful in the future.
Thank you, Franc.