What is hardenability curve? 1

[unp1]

Hi friends,

What is hardenability curve? Recently I came across this term and don’t know anything about it. I am looking for hardenability curves for different grades of stainless steel. Where can I find this information? Could anyone please help me?

Thanks.

 

[metengr]

The hardenability curve that you indicated above is probably best described by the Jominy Curve or otherwise known as a Jominy Hardenability Curve. The Jominy curves are formulated based on a standard test method. To summarize, a test specimen (round bar of predetermined size)is heated to a specific, elevated temperature range and quenched in a test fixture. Hardness is plotted as a function of distance along the test bar. The resulting curve is called a Jominy curve that could be used for comparing hardenability between various steels.

The Jominy curves are used for carbon and low alloy steel. When it comes to stainless steel, the only grades that are hardenable by heat treatment are the martensitic grades and precipitation hardening grades. Keep in mind that the stainless steel grades are alloyed so that the transformation is uniform throughout. In other words, you do not have multiple transformation products with heat treatable stainless steels like you do with carbon and low alloy steels. Thus, you probably will not find any meaningful hardenability curves for heat treatable stainless steel alloys.