EN_US-Product-Cold-rolled-AHSS-All Grades OverviewTSUK

Overview

The good formability of our advanced and ultra high-strength steels (AHSS / UHSS) allows the user to increase the strength of the finished automotive components in body in white applications (BIW) by exploiting the high work-hardening characteristics. Substitution of high strength steel grades provides opportunities to reduce thickness while maintaining the in-service performance, resulting in potential cost and mass savings.

Dual phase grades

Cold-rolled dual phase steels allow you to increase the strength of the finished component or reduce the thickness of the steel - or both. By increasing product performance and helping reduce weight, these steels support you to achieve your optimum performance parameters. The use of dual phase grades increases the output from each tonne of steel and produces products that are strong, light and safe under load. High strain-hardening capacity ensures our dual phase steels have good formability.

Hot forming steel - 22MnB5

Our 22MnB5 product is an uncoated, ultra high-strength hot forming steel. It combines a strength level of 1500 N/mm² with excellent shape accuracy. Compared with conventional high-strength, low-alloy grades, 22MnB5 offers real opportunities for weight reduction through down-gauging. It also ensures good repeatability in long production runs when compared with cold press forming.

Applications

Body in white (BIW), structural and reinforcement components and lightweight structural seat components

Relationship with standards

Tata Steel can supply the following cold-rolled advanced and ultra high-strength steel grades:

Tata Steel	VDA	EN 10338: 2015	EN 10083: 2009
DP600	CR330Y590T-DP	HCT590X	-
DP800	CR440Y780T-DP	HCT780X	-
22MnB5	-	-	20MnB5 ¹

^1. This grade is also widely known as 22MnB5.

EN-Product-Cold-rolled-All Grades Surface aspectsTSUK

Surface aspects

Surface quality

Surface quality A

Defects that do not influence the formability or the application of surface coatings are permitted. They are defects such as pores, minor scratches, slight indentations, small grooves or slight discolouration.

Surface quality B

The better side must be free of defects that can spoil the uniform appearance of a high-quality paint or of an electrolytic coating. The other side must at least conform to surface quality A. Not all combinations of thickness and width are available in surface quality B. Please contact us for details.

Inspected side

As a rule, the upper side of the strip is inspected; on request, the strip can be wound so that the inspected side is the underside.

Surface texture/roughness

Cold-rolled annealed and skin-passed steel is available in several surface textures. Unless specified otherwise, Tata Steel will supply normal roughness. The table below shows the range of surface textures according to EN 10130:2006.

		Roughness R_a (µm)
EN 10130: 2006	Symbol	cut off 0.8 mm
extra-bright ¹	-	≤ 0.3
bright	b	≤ 0.4
semi-bright	g	≤ 0.9
normal	m	0.6 - 1.9
rough	r	> 1.6
extra-rough ²	-	3.5 - 5

^1. Not in EN 10130:2006 - Tata Steel’s own specification. Please contact us regarding the availability
^2. Not in EN 10130:2006 - Tata Steel’s own specification, measured with a cut off of 2.5 mm
Other surface textures are available to meet your requirements - please contact us for details.

^{Preservative oil}

The standard oil applied by Tata Steel acts as a protective coating. Other types of oil may be available to meet your requirement.
Tata Steel offers a range of oiling levels from 0.25 - 1.7 g/m² per side.
Other oiling levels are available on request. Tata Steel is not responsible for the risk of corrosion during storage or shipment if material is ordered in the un-oiled condition.

^{Surface cleanliness}

Tata Steel can guarantee improved surface cleanliness on request for batch-annealed products. The cleanliness is tested with a tape test, in which the loss of reflection is measured. The reflection gives an indication of the oil residue on the annealed product. Two levels of loss of reflectivity are available for batch annealed products: a maximum of 20% or a maximum of 30%. Continuously-annealed products typically exhibit a loss of reflection up to around 10%.