ASM Online Member Community

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Hi Sanjay,

Great question! Untempered martensite is what you get just after quenching. It leaves a very needle-like microstructure that's very hard but also quite brittle. Tempering is then performed at much lower temperatures to make the microstructure more homogenous, shorter, and then also much more ductile. The Charpy impact toughness rises substantially and the strength decreases by quite a bit. In some cases, like knives, swords, and blades, the harder material is better so no quenching is used. Conversely, in most engineering applications you need some toughness (aka the resistance to growth of a crack), so the tradeoff of a moderate reduction in strength is worth it. Summing up:

Tempered martensite has been heat treated to make it slightly softer but much more ductile (and tougher).
Untempered martensite is fresh out of quenching, very hard but not very tough.

Best regards!

------------------------------
Joshua Jackson
CEO
US Corrosion Services LLC
Houston TX
------------------------------

Original Message:
Sent: 03-08-2021 11:14
From: Sanjay Kulkarni
Subject: Martensite in Steel

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Hi Joshua,
Thanks for quick response, so the question remains is should I call it un-tempered martensite or just martensite in the report. As far as I know as per metallurgy both types are martensite since they are not tempered. Which is the most appropriate to address in reports martensite or un- tempered martensite for as quenched microstructures?
Regards,

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Original Message:
Sent: 03-09-2021 01:10
From: Joshua Jackson
Subject: Martensite in Steel

Hi Sanjay,

Great question! Untempered martensite is what you get just after quenching. It leaves a very needle-like microstructure that's very hard but also quite brittle. Tempering is then performed at much lower temperatures to make the microstructure more homogenous, shorter, and then also much more ductile. The Charpy impact toughness rises substantially and the strength decreases by quite a bit. In some cases, like knives, swords, and blades, the harder material is better so no quenching is used. Conversely, in most engineering applications you need some toughness (aka the resistance to growth of a crack), so the tradeoff of a moderate reduction in strength is worth it. Summing up:

Tempered martensite has been heat treated to make it slightly softer but much more ductile (and tougher).
Untempered martensite is fresh out of quenching, very hard but not very tough.

Best regards!

------------------------------
Joshua Jackson
CEO
US Corrosion Services LLC
Houston TX

Original Message:
Sent: 03-08-2021 11:14
From: Sanjay Kulkarni
Subject: Martensite in Steel

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Usualyy, for as-quenced microstructure I use "untemperd martensite" or "tetragonal martensite".
Regards,

------------------------------
Andrea Talamini Minotto
Villorba Treviso
------------------------------

Original Message:
Sent: 03-09-2021 08:44
From: Sanjay Kulkarni
Subject: Martensite in Steel

Hi Joshua,
Thanks for quick response, so the question remains is should I call it un-tempered martensite or just martensite in the report. As far as I know as per metallurgy both types are martensite since they are not tempered. Which is the most appropriate to address in reports martensite or un- tempered martensite for as quenched microstructures?
Regards,

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056

Original Message:
Sent: 03-09-2021 01:10
From: Joshua Jackson
Subject: Martensite in Steel

Hi Sanjay,

Great question! Untempered martensite is what you get just after quenching. It leaves a very needle-like microstructure that's very hard but also quite brittle. Tempering is then performed at much lower temperatures to make the microstructure more homogenous, shorter, and then also much more ductile. The Charpy impact toughness rises substantially and the strength decreases by quite a bit. In some cases, like knives, swords, and blades, the harder material is better so no quenching is used. Conversely, in most engineering applications you need some toughness (aka the resistance to growth of a crack), so the tradeoff of a moderate reduction in strength is worth it. Summing up:

Tempered martensite has been heat treated to make it slightly softer but much more ductile (and tougher).
Untempered martensite is fresh out of quenching, very hard but not very tough.

Best regards!

------------------------------
Joshua Jackson
CEO
US Corrosion Services LLC
Houston TX

Original Message:
Sent: 03-08-2021 11:14
From: Sanjay Kulkarni
Subject: Martensite in Steel

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Thanks Andrea. I should  designate un-tempered martensite instead of martensite. Clarifies my confusion.

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Original Message:
Sent: 03-09-2021 08:54
From: Andrea Talamini Minotto
Subject: Martensite in Steel

Usualyy, for as-quenced microstructure I use "untemperd martensite" or "tetragonal martensite".
Regards,

------------------------------
Andrea Talamini Minotto
Villorba Treviso

Original Message:
Sent: 03-09-2021 08:44
From: Sanjay Kulkarni
Subject: Martensite in Steel

Hi Joshua,
Thanks for quick response, so the question remains is should I call it un-tempered martensite or just martensite in the report. As far as I know as per metallurgy both types are martensite since they are not tempered. Which is the most appropriate to address in reports martensite or un- tempered martensite for as quenched microstructures?
Regards,

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056

Original Message:
Sent: 03-09-2021 01:10
From: Joshua Jackson
Subject: Martensite in Steel

Hi Sanjay,

Great question! Untempered martensite is what you get just after quenching. It leaves a very needle-like microstructure that's very hard but also quite brittle. Tempering is then performed at much lower temperatures to make the microstructure more homogenous, shorter, and then also much more ductile. The Charpy impact toughness rises substantially and the strength decreases by quite a bit. In some cases, like knives, swords, and blades, the harder material is better so no quenching is used. Conversely, in most engineering applications you need some toughness (aka the resistance to growth of a crack), so the tradeoff of a moderate reduction in strength is worth it. Summing up:

Tempered martensite has been heat treated to make it slightly softer but much more ductile (and tougher).
Untempered martensite is fresh out of quenching, very hard but not very tough.

Best regards!

------------------------------
Joshua Jackson
CEO
US Corrosion Services LLC
Houston TX

Original Message:
Sent: 03-08-2021 11:14
From: Sanjay Kulkarni
Subject: Martensite in Steel

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------

Untempered martensite should be the right term in your report to distinguish it from tempered martensitic structure. This will provide clarity in your report, particularly for readers who may not have strong Materials/Metallurgical background. 

Nnaemeka

------------------------------
Nnaemeka Ugodilinwa
Process Engineer
StandardAero
Winnipeg MB
2043187632
------------------------------

Original Message:
Sent: 03-09-2021 08:44
From: Sanjay Kulkarni
Subject: Martensite in Steel

Hi Joshua,
Thanks for quick response, so the question remains is should I call it un-tempered martensite or just martensite in the report. As far as I know as per metallurgy both types are martensite since they are not tempered. Which is the most appropriate to address in reports martensite or un- tempered martensite for as quenched microstructures?
Regards,

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056

Original Message:
Sent: 03-09-2021 01:10
From: Joshua Jackson
Subject: Martensite in Steel

Hi Sanjay,

Great question! Untempered martensite is what you get just after quenching. It leaves a very needle-like microstructure that's very hard but also quite brittle. Tempering is then performed at much lower temperatures to make the microstructure more homogenous, shorter, and then also much more ductile. The Charpy impact toughness rises substantially and the strength decreases by quite a bit. In some cases, like knives, swords, and blades, the harder material is better so no quenching is used. Conversely, in most engineering applications you need some toughness (aka the resistance to growth of a crack), so the tradeoff of a moderate reduction in strength is worth it. Summing up:

Tempered martensite has been heat treated to make it slightly softer but much more ductile (and tougher).
Untempered martensite is fresh out of quenching, very hard but not very tough.

Best regards!

------------------------------
Joshua Jackson
CEO
US Corrosion Services LLC
Houston TX

Original Message:
Sent: 03-08-2021 11:14
From: Sanjay Kulkarni
Subject: Martensite in Steel

What is the correct way to call Martensite in steel? Is it un-tempered Martensite? Or martensite only?
I have limited years of experience in steel alloys processing, but never came across the term, "un tempered martensite" for martensite microstructure,  unless there is presence of  residual martensite in tempered martensite microstructure. Please advice.

Sanjay Kulkarni

Materials Engineer

MSSC

a group company of MITSUBISHI STEEL MFG. CO., LTD.

 

------------------------------
Sanjay Kulkarni
Materials Engineer
MSSC
Troy, MI
248-840-1056
------------------------------