What is the difference between 4140 and 4140h

Login to Your Account. Remember Me? Register Forgot password? What's New? Page 1 of 2 1 2 Last Jump to page: Results 1 to 20 of Thread Tools Show Printable Version. Those are usually used interchangeably. TGP can be hardened or not Rob F. View Profile View Forum Posts. Originally Posted by fettersp. That's good to know. But I'm guessing annealed cant br interchangeable since it has lead in it?? CarbideBob , Ray Behner liked this post. Originally Posted by Rob F.

I must be thinking l? I remember someone telling me it had lead in it to make it easier to machine. I'm just confused on a bit. Is annealed the same as PH or can it be interchangeable?? I mean what else? Do me a favor, click this little button and subscribe it will help the channel.

Thank you and I appreciate it! Over the last several weeks we have been talking about special types of alloy steels. Alloy steels like these develop their best properties after heat treatment. How do we compare alloys and know what to expect after heat treatment? Alloys are very different from each other. Even variations within the allowable chemistry limits of an alloy can affect the hardness profile that can be achieved.

The lower the finishing temperature from forging, the finer will be the grain size. This kind of treatment is best used for parts with simple shapes. It is safe to say that experience alone will decide the best type of annealing treatment to be used prior to machining. This process is defined as heating a steel to a temperature above the ferrite to austenite transformation range and then cooling in air to a temperature well below this transformation range.

This treatment may be carried out on forged products as a conditioning treatment prior to final heat treatment. Normalizing also serves to refine the structure of forgings that might have cooled non-uniformly from their forging operation. In fact when forgings are normalized before, say, carburizing or hardening and tempering, the upper range of normalizing temperatures is used.

When normalizing is the final heat treatment, the lower temperature range is used.