Extended Information

The steel can be divided into further subgroups based on the yield point, the force required to deform the steel. These groups are:

HS (HIGH STRENGTH STEEL) 

Steel with a yield point between 220-450 MPa (marked light grey in the graphic).

There are three main types of steel within this group:

• Phosphorous-alloy steel: 

  This steel has a higher strength as a result of the use of phosphorous alloy.

• HSLA steel (High Strength Low Alloy): 

  This is a low alloy steel, where alloys such as Vanadium, Niobium or Titanium are used to increase the yield strength.

• DP steel (Dual Phase): 

  This steel is strengthened by heat treatment during manufacture. A two phase structure of iron and carbon is formed. DP steel will lose its strength if it is exposed to temperatures in excess of 300°C.

EHS (EXTRA HIGH STRENGTH STEEL) 

Has a yield point between 450-800 MPa. EHS is light grey in the graphic.

Both HSLA and DP steel are within this group, although the strength has been further increased through the addition of greater alloy substances.

UHS (ULTRA HIGH STRENGTH STEEL) 

Has a yield point between 800-1400 MPa. UHS is dark grey in the graphic.

There are two main types of steel within this group:

• DP steel: 

  The strength is even higher due to an advanced manufacturing process and the greater quantities of alloys.

• BORON steel: 

  The additional of boron gives this steel greater strength. BORON steel also contains relatively high quantities of carbon. The profiles of the sheets are formed between a press and pad while the metal is red hot. The material also hardens here. These sections must not be straightened because of their extremely high strength.