Quality	Standard	Possible coatings	Alloy concept
CR4	VDA 239-100	UC, EG, GI, GA, AS, ZM	Non IF or IF

Testing direction	Yield Point Re (MPa)	Tensil Strength Rm (MPa)	Elongation type 1 A50 (in %)	Type 2 A80 (in %)	Type 3 A50 (in %)	r 90/20	rm/20	n10-20/Ag
Q	140 – 180	270 – 330	≥ 40	≥ 39	≥ 42	≥ 1,9	≥ 1,6	≥ 0,20

CR4, also known as special drawing grade, is a cold-rolled steel specially developed for the extremely demanding requirements of deep-drawing applications. The VDA 239-100 standard defines the technical specifications of this material, which is characterized by exceptional formability, high surface quality and outstanding dimensional stability.

Material properties and composition
The exceptional performance of CR4 is based on its fine-grained microstructure, which is achieved through precise control of the rolling and annealing process. This structure results in the following properties:

The chemical composition of CR4 is designed to provide an optimum balance between formability and strength, using elements such as manganese and small amounts of carbon.

Typical applications
CR4 is preferably used in industries where complex components with the highest demands on deformation and surface quality are required. Examples of typical applications are

Advantages compared to other grades
Compared to CR3 (special deep-drawing grade), CR4 offers even greater formability and is therefore particularly suitable for extremely complex geometries. The combination of very low yield strength, high forming potential and resistance to ageing clearly sets CR4 apart from other deep-drawing grades.

Conclusion
CR4 (special drawing grade) is the first choice for extremely demanding deep-drawing applications where the highest requirements are placed on formability, surface quality and dimensional accuracy. In accordance with the VDA 239-100 standard, this steel offers an ideal solution for the production of complex components in the automotive and electronics industries. Its properties enable reliable and economical production that meets the highest quality standards.