Bainite for dynamic stress

Sophisticated bending

Our bainitic hardened and tempered PT-strip (pre-tempered) has an ideal combination of pre-adjusted component strength, good formability and good bendability. It has optimal spring properties, even for dynamic, highly-stressed parts. It is used, for example, in connecting, fastening and spring clips in mounting applications.  

Waelzholz owns special, high-performance machinery for bainitic hardening and tempering and is specialized in the production of PT-strip. This is how we guarantee absolutely homogeneous processing and forming properties as well as constant mechanical-technological characteristic values. Our customers benefit from the high- reproducibility of their components, as this translates to process stability. The greatest advantage of using PT-strip is the absence of time-consuming and expensive piece hardening. Stamped, bent and formed parts can be manufactured in one single step without any deforming or heat cracks. The result is optimal processing efficiency.

Good Formability despite high strengths

Specifically, the good formability and bendability facilitate a wide range of demanding forming operations such as contours of stamped holes with a collar or dome-shaped drawing, notches and beading.

The differences between longitudinal bending and transverse bending are also minimal thanks to the homogeneous and fine-grained microstructure of the material. Because of this characteristic, our customers profit from maximum reproducibility of their parts and extremely high process reliability.

Sample application

PT 120 with a thickness of 1.7 mm (0.067") and a tensile strength of Rm = 1150 MPa (167 ksi)

Bending radius longitudinal to rolling direction
2  Collaring hole by drawing
Bending radius transversal to rolling direction
4  Notch

 

You will find the possible bending radii according to material thickness in the following table.

Burr is located in inner diameter PT-strip / Minimal bending radii at 90° bending

mm
EN 10132-4 Transversal to RD [mm] Longitudinal to RD [mm]
PT90
PT100
PT120
PT140

Grade and raw material overview / delivery types

PT90 PT100 PT120 PT140
Grade
acc. to EN 10132-3 and EN 10132-4
36Mn5 C45E C60S C75S
Tensile strength [MPa] 800 - 1000 900 - 1100 1100 - 1300 1300 - 1500
Yield/tensile ratio [%] ca. 80 - 85 ca. 80 - 85 ca. 80 - 85 ca. 80 - 85
A80 [%] min. 16 min. 14 min. 9 min. 5
Maximum longitudinal bending angle
(bending radius = material thickness) [°]
> 110 > 100 > 90 > 50
Maximum transversal bending angle
(bending radius = material thickness) [°]
> 120 > 110 > 100 > 60
Thickness [mm]
dimension tolerance acc. to DIN EN
10140
0.2 - 3.0 0.2 - 3.0 0.2 - 3.0 0.2 - 3.0
Width [mm]
dimension tolerance acc. to DIN EN
10140
5 - 450 5 - 450 5 - 450 5 - 450
Surface
decarburization
max. 2 % of thickness
bright/ grey-blue finish bright/ grey-blue finish bright/ grey-blue finish bright/ grey-blue finish
Delivery condition skin passed (+LC) or stretch-bended

For more information on the PT-strip products, please refer to data sheets provided.

You have any questions concerning our steel materials or would like to send us an e-mail?