Martensitic and ferritic steels are both kinds of stainless steel.

Ferritic steels are magnetic and have low carbon content, making them resistant to oxidation. They also have high tensile strength and are easy to form and weld. Martensitic steels, on the other hand, have higher carbon content and are hardenable. This type is best suited for applications that require high strength and wear resistance.
The main difference between the two steels is their composition. Ferritic is composed of mostly iron and chromium. It has small amounts of other elements as well such as molybdenum, nickel, and titanium. On the other side, martensitic steels contain more carbon. It also has other alloying elements contents such as vanadium and manganese. This higher carbon content makes martensitic harder and more wear-resistant than the ferritic type of stainless steel.
When it comes to machinability and weldability, ferritic stainless steels have an advantage over martensitic. Ferritic are easier to machine and weld. While martensitic steels are more difficult due to their higher carbon content.

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