Do you, by any chance, require tools which can stay sharp for extended periods, maintain precise shapes, and withstand constant friction? If you do, then the answer may either be 1.2379 or D2 cold work tool steel. Both steels are specialty cold work tool steels that are renowned for having outstanding wear resistance, hardenability, and dimensional stability, making either a great choice for a variety of tooling applications.

Understanding 1.2379 Steel

1.2379 steel is also known as designations DIN 1.2379 or X153CrMoV12. It is a type of cold work steel that has unique properties brought about by its specific chemical composition. It is quite similar to another cold work tool steel known as D2 in composition except for certain differences.

• Contains Carbon (C) - The hardenability of 1.2379 tool steel comes from a high carbon content that is typically within the range of 1.45% to 1.65%. It is this level of carbon that greatly contributes to the steel’s wear resistance. Almost, but not quite similar, D2 steel has a high carbon content of about 1.4% to 1.6% providing it with the ability to also resist abrasion and wear.
• Contains Chromium (Cr) – Both D2 and 1.2379 tool steels contain chromium which is a vital element for protection against corrosion and also for wear resistance.
• Contains Molybdenum (Mo) – 1.2379 steel contains molybdenum which helps to enhance its hardenability and allows for a deeper hardening throughout the steel’s core. This can be extremely beneficial for thicker tools or for tools requiring wear resistance throughout. When it comes to D2 steel, there are variations of it which may contain very small amounts of molybdenum, but it is not a guaranteed element for its composition. The properties of D2 mainly rely on chromium and carbon.
• Contains Vanadium (V) – Although the exact amount of vanadium can  slightly vary depending on the manufacturer or the specific standard, both 1,2379 and D2 steel contain vanadium and greatly benefit from its presence.

Uses & Suitable Applications

Both cold work steel known as 1.2379 and D2 excel in cold working tasks that demand exceptional levels of resistance to wear, good hardenability, and dimensional stability. And these are the properties which make them the ideal steel choice for cold work tools like blades used in shaping sheet metals, dies, and punches. Both offer wear resistance which help tools maintain their sharp edges, while their dimensional stability greatly minimizes warping or bending for more accurate cold working. Both 1.2379 and D2 steel are also well suited for wear parts like bearings and rollers as their friction resistance can be vital.

Why Choose 1.2379 Cold Work Steel

Although both D2 and 1.2379 are great choices for cold working and they are quite similar in many ways -- in applications that demand deepest possible hardening of thicker tools, 1.2379 may very well be the better choice due to its molybdenum content. The presence of molybdenum in the steel greatly enhances its hardenability and maximum wear resistance. However, it is important to note that the final decision will greatly depend on a project’s specific needs and requirements.