Quality	Standard	Material No.	Old designation
DD12	DIN EN 10111	1.0398	StW 23

Testing direction	Yield strength ReL (MPa) 1 ≤ 2 mm	ReL (MPa) 2 ≤ 11 mm	Tensile strength Rm (MPa)	Elongation A80 (in %) 1 ‘ 1.5 mm	A80 (in %) 1.5 ≤ 2 mm	A80 (in %) 2 ≤ 3 mm	A5 (in %) 3 ≤ 11 mm
Q	170 – 340	170 – 320	≤420	24	25	26	30

Hot-rolled steel DD12 is a non-alloy steel produced in accordance with the EN 10111 standard. It is characterized by its good formability, weldability and machinability. With a maximum tensile strength of 420 MPa, it is one of the soft steels.

Production and properties:
This grade is usually rolled from slabs that are heated to temperatures of over 1000 °C. Rolling gives the steel its final shape and properties. DD12 has a ferritic-pearlitic microstructure, which gives it its good formability and toughness.

Applications:
DD12 is used in a variety of applications due to its properties, such as:
– Automotive industry: body parts, wheels, chassis components
– Construction industry: Load-bearing structures, profiles, pipes
– Household appliances: housings, sheet metal
– Mechanical engineering: transmission parts, housings, shafts
– Agricultural equipment: plows, trailers, tractors

Advantages:
– Good formability: DD12 can be easily formed into various shapes, making it ideal for cold forming.
– Good weldability: DD12 can be welded using all common welding processes without preheating.
– Toughness: DD12 is a tough material that can withstand high loads.
‘- Inexpensive: DD12 is a relatively inexpensive material.

Disadvantages:
– Lower strength: DD12 has a lower strength than quenched and tempered or alloyed steels.

Surface treatment:
DD12 can be coated using various methods to protect against corrosion, such as:
– Galvanizing: Galvanizing protects the steel from corrosion by applying a layer of zinc.
– Painting: Painting can be used to coat the steel in different colors and protect it from corrosion at the same time.
– Coating with plastics: Plastic coatings offer good corrosion protection and are abrasion-resistant at the same time.

Comparison with DD11:
DD12 is somewhat stronger than DD11 and has a higher yield strength. This means that DD12 can withstand more stress before it plastically deforms. However, DD12 is also slightly less tough.

Conclusion
In summary, it can be said that hot-rolled DD12 steel is an extremely versatile material due to its good formability, weldability and machinability. Thanks to its properties, it is used in numerous applications and is very popular for cold forming.