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  • 1.  More insight into DI values as they pertain to heat treatment

    Posted 07-07-2023 10:54

    To all:

    Im new to the field and am interested into some insight of DI vlaues as they pertain to heat treatment. I am learning as I go but many have aided me with valuable knowledge so far. We do not have a metallurgist anymore so I have tried to step up as a career path change from industrial electrician with induction heating experieence. My question is we are always in caution of a higher DI as it makes our product harder to mahcine prior to heat trearment via induction. I have searched to see what concerns may be if our Di value is lower. Not that it puts us out of spec or tolerance but Im just curious as to its possibility of concern.



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    Rodney Recore
    Plant Process Metallurgist
    Gasport NY
    (716) 998-9823
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  • 2.  RE: More insight into DI values as they pertain to heat treatment

    Posted 07-10-2023 10:35

    Hi Rodney,

    The DI is hardenability (how hard the part gets after heat-treating) of the steel after heat treatment. It prevents sag in the manufactured components Higher the DI lower the sag after putting it in the service. I am in coil spring and other suspension components manufacturing business where sag is not desired.

    Thanks,



    ------------------------------
    Sanjay Kulkarni
    Materials Engineer
    MSSC
    2040 Crooks RD, Suite A
    Troy, MI 48084
    sanjay.kulkarni@msscna.com
    Cell: 248-840-1056
    ------------------------------



  • 3.  RE: More insight into DI values as they pertain to heat treatment

    Posted 07-10-2023 12:02

    Sanjay,

    Thanks for your feedback! We are in the S cam brake shoe business. We usually have to worry on the high end of our spec for DI but I was never in a situation with a lower DI value. It is on bar steel with a diameter range from 1 1/2" to a touch under 2 ". It has been truly a learning curve here for myself. I'm sure you will see more questions posted as I venture further into my career here.



    ------------------------------
    Rodney Recore
    Plant Process Metallurgist
    Brunner International
    Gasport NY
    (716) 998-9823
    ------------------------------

    Original Message


  • 4.  RE: More insight into DI values as they pertain to heat treatment

    Posted 07-10-2023 13:50

    Hi Roney,

    It sounds like you are using approximately 2" dia. steel bars. We also use those sizes in making Torsion bars where higher DI is critical.

    I use 4-4.5" for our application for the alloy SAE 9254. Please refer to SAE J406 test method for more details.



    ------------------------------
    Sanjay Kulkarni
    Materials Engineer
    MSSC
    2040 Crooks RD, Suite A
    Troy, MI 48084
    sanjay.kulkarni@msscna.com
    Cell: 248-840-1056
    ------------------------------

    Original Message