hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.

wrote in message
oups.com...
hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.


With many steels in which a completely spheroidal structure is difficult to
obtain with a regular procedure, preheating is helpful. This is mainly
applicable to hypoeutectoid steels, but it has also been useful with some
low alloy hypereutectoid steels. Preheating consists of heating the steel
at a temperature about 25 to 100 degrees F below the critical before the
steel is austenitized. The preheating may be followed by cooling to room
temperature before the austenitizing heating, but obviously it is more
economical to hold the steel at the preheating temperature and then to raise
it immediately to the austenitizing temperature. The purpose of preheating
is to agglomerate the carbides in the steel so that they will be more
resistant to solution in the austenite during the subsequent heating. The
presence of undissolved carbides, or carbon concentration gradients, in the
austenite is conducive to the formation of a spheroidal, rather than a
lamellar, structure when the austenite transforms. This treatment has been
found effective in a number of carbon and low alloy steels with 0.40 to
0.80% C. The temperature for 1018 would be from 1575 to 1650 F and furnace
cooling at 50 degrees per hour to 1300 degrees.

Dixon

"Dixon" wrote in message
...

wrote in message
oups.com...
hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.


With many steels in which a completely spheroidal structure is difficult
to
obtain with a regular procedure, preheating is helpful. This is mainly
applicable to hypoeutectoid steels, but it has also been useful with some
low alloy hypereutectoid steels. Preheating consists of heating the steel
at a temperature about 25 to 100 degrees F below the critical before the
steel is austenitized. The preheating may be followed by cooling to room
temperature before the austenitizing heating, but obviously it is more
economical to hold the steel at the preheating temperature and then to
raise
it immediately to the austenitizing temperature. The purpose of
preheating
is to agglomerate the carbides in the steel so that they will be more
resistant to solution in the austenite during the subsequent heating. The
presence of undissolved carbides, or carbon concentration gradients, in
the
austenite is conducive to the formation of a spheroidal, rather than a
lamellar, structure when the austenite transforms. This treatment has
been
found effective in a number of carbon and low alloy steels with 0.40 to
0.80% C. The temperature for 1018 would be from 1575 to 1650 F and
furnace
cooling at 50 degrees per hour to 1300 degrees.

Ok for steel with 40 to 80 points of carbon. But 1018 is 18 points. How is
the spheroidization occuring with such low percentages of carbon?

--
Ed Huntress

"Ed Huntress" wrote in message
...
"Dixon" wrote in message
...

wrote in message
oups.com...
hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.


With many steels in which a completely spheroidal structure is difficult
to
obtain with a regular procedure, preheating is helpful. This is mainly
applicable to hypoeutectoid steels, but it has also been useful with some
low alloy hypereutectoid steels. Preheating consists of heating the
steel
at a temperature about 25 to 100 degrees F below the critical before the
steel is austenitized. The preheating may be followed by cooling to room
temperature before the austenitizing heating, but obviously it is more
economical to hold the steel at the preheating temperature and then to
raise
it immediately to the austenitizing temperature. The purpose of
preheating
is to agglomerate the carbides in the steel so that they will be more
resistant to solution in the austenite during the subsequent heating.
The
presence of undissolved carbides, or carbon concentration gradients, in
the
austenite is conducive to the formation of a spheroidal, rather than a
lamellar, structure when the austenite transforms. This treatment has
been
found effective in a number of carbon and low alloy steels with 0.40 to
0.80% C. The temperature for 1018 would be from 1575 to 1650 F and
furnace
cooling at 50 degrees per hour to 1300 degrees.

Ok for steel with 40 to 80 points of carbon. But 1018 is 18 points. How is
the spheroidization occuring with such low percentages of carbon?

--
Ed Huntress

Without going into a lot of reasearch, I would have to say you're right. The
term spheroidization, at a certain carbon point probably "morphs" with the
term "normalization". I would suspect the original question had to do with
improved machining properties, which I would personally handle with
machining techniques.

Dixon

"Dixon" wrote in message
...

"Ed Huntress" wrote in message
...
"Dixon" wrote in message
...

wrote in message
oups.com...
hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low
carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.


With many steels in which a completely spheroidal structure is
difficult
to
obtain with a regular procedure, preheating is helpful. This is mainly
applicable to hypoeutectoid steels, but it has also been useful with
some
low alloy hypereutectoid steels. Preheating consists of heating the
steel
at a temperature about 25 to 100 degrees F below the critical before
the
steel is austenitized. The preheating may be followed by cooling to
room
temperature before the austenitizing heating, but obviously it is more
economical to hold the steel at the preheating temperature and then to
raise
it immediately to the austenitizing temperature. The purpose of
preheating
is to agglomerate the carbides in the steel so that they will be more
resistant to solution in the austenite during the subsequent heating.
The
presence of undissolved carbides, or carbon concentration gradients, in
the
austenite is conducive to the formation of a spheroidal, rather than a
lamellar, structure when the austenite transforms. This treatment has
been
found effective in a number of carbon and low alloy steels with 0.40 to
0.80% C. The temperature for 1018 would be from 1575 to 1650 F and
furnace
cooling at 50 degrees per hour to 1300 degrees.

Ok for steel with 40 to 80 points of carbon. But 1018 is 18 points. How
is
the spheroidization occuring with such low percentages of carbon?

--
Ed Huntress

Without going into a lot of reasearch, I would have to say you're right.
The
term spheroidization, at a certain carbon point probably "morphs" with the
term "normalization". I would suspect the original question had to do with
improved machining properties, which I would personally handle with
machining techniques.

Dixon

Yeah, it could be. I'm not presuming to know the answer, I was just curious.

The problem with learning technical subjects like metallurgy at the
*technician's* level, as I have, rather than at the engineering level, is
that you can be victimized by the simplifications they use to teach you. I
was taught that speroidization requires a lot of dissolved carbon, which is
precipitated out of the cooling metal as spheres or other rounded, chunky
shapes, rather than as flakes or laminations. It's mostly of interest in
relation to cast irons.

But there could well be something else going on here that I'm unaware of,
and it would be interesting to know if you can get spheroidization in
low-carbon steel.

--
Ed Huntress

"Ed Huntress" wrote in message
...
"Dixon" wrote in message
...

"Ed Huntress" wrote in message
...
"Dixon" wrote in message
...

wrote in message
oups.com...
hi everyone, i am came across this group while searching for some
information. looks like very useful.

i have question regading heat treatment for EN353 (low alloy-low
carbon
steel,C-.16,M-.8, Cr-1.2, Ni-1) to achieve complete spheroidzation.
Which type of treamtnet will be good for achieving complete
spheroidization?

Please share any type of heat treament cycle being used industrially
for spheroidzation.

awaiting responses.


With many steels in which a completely spheroidal structure is
difficult
to
obtain with a regular procedure, preheating is helpful. This is
mainly
applicable to hypoeutectoid steels, but it has also been useful with
some
low alloy hypereutectoid steels. Preheating consists of heating the
steel
at a temperature about 25 to 100 degrees F below the critical before
the
steel is austenitized. The preheating may be followed by cooling to
room
temperature before the austenitizing heating, but obviously it is more
economical to hold the steel at the preheating temperature and then to
raise
it immediately to the austenitizing temperature. The purpose of
preheating
is to agglomerate the carbides in the steel so that they will be more
resistant to solution in the austenite during the subsequent heating.
The
presence of undissolved carbides, or carbon concentration gradients,
in
the
austenite is conducive to the formation of a spheroidal, rather than a
lamellar, structure when the austenite transforms. This treatment has
been
found effective in a number of carbon and low alloy steels with 0.40
to
0.80% C. The temperature for 1018 would be from 1575 to 1650 F and
furnace
cooling at 50 degrees per hour to 1300 degrees.

Ok for steel with 40 to 80 points of carbon. But 1018 is 18 points. How
is
the spheroidization occuring with such low percentages of carbon?

--
Ed Huntress

Without going into a lot of reasearch, I would have to say you're right.
The
term spheroidization, at a certain carbon point probably "morphs" with
the
term "normalization". I would suspect the original question had to do
with
improved machining properties, which I would personally handle with
machining techniques.

Dixon

Yeah, it could be. I'm not presuming to know the answer, I was just
curious.

The problem with learning technical subjects like metallurgy at the
*technician's* level, as I have, rather than at the engineering level, is
that you can be victimized by the simplifications they use to teach you. I
was taught that speroidization requires a lot of dissolved carbon, which
is
precipitated out of the cooling metal as spheres or other rounded, chunky
shapes, rather than as flakes or laminations. It's mostly of interest in
relation to cast irons.

But there could well be something else going on here that I'm unaware of,
and it would be interesting to know if you can get spheroidization in
low-carbon steel.

--
Ed Huntress


Ed, I talked to a metallurgist friend and he said that the spheroidization
process at 18 points carbon would be so insignificant that you would never
notice a machining change. However, there would be very slight
spheroidization of the small % carbon, but it would only be detectable by
microscope. Something about pearlite strings. I personally never heard of
anyone bothering with it in steel, only cast iron.

Dixon

"Dixon" wrote in message
...


snip


Ed, I talked to a metallurgist friend and he said that the spheroidization
process at 18 points carbon would be so insignificant that you would never
notice a machining change. However, there would be very slight
spheroidization of the small % carbon, but it would only be detectable by
microscope. Something about pearlite strings. I personally never heard of
anyone bothering with it in steel, only cast iron.

Dixon

Thanks, Dixon. It's good to hear it from someone who's really into it.

--
Ed Huntress

thanks all for the replies.

my aim of spheroidizing the steel is to reduce hardness and increase
machinability of the steel..

how to determine the cooling rates?1.cooling rate while cooling to room
temperature 2cooling rate frm above critical temp to below critical
temperature where we hold the sample

if possible please tell me the standard treatment you follow in
industry or tell the resources where i can find out information about
treamments being followed in industry to achieve spheroidization??
regards
vikram