Safe – Ballistic protection steel

Properties

Chemical composition – Bucket analysis – Maximum mass %

1) Carbon equivalent according to ASTM A6/A6M, i.e.: CE = C + [Mn/6] + [(Cr + Mo + V)/5] + [(Ni + Cu)/15]

Mechanicalproperties(inbothdirections)

*Minimumguaranteedvalue:477 HBW

2) Average of 3 tests. Single value min 70% of specified average.
3) For nominal thicknesses under 11mm, sub-size specimens are used. The specified minimum value is then proportional to the specimen cross section.
Brinell hardness test according to (EN ISO 6506-1), on at least one plate per heat treatment batch, on two places, one at each end of a diagonal, on a milled surface 0,5 to 1mm below plate surface.

In service conditions

1) multihittestcondition:equilateraltrianglewithsides4±1timeprojectilecaliber

²⁾ skineffect:thearmorsteelistestedwitha1mmmild-steelplateplaced,infrontofit,atastand-offdistanceof10mm.

Plate processing

Cutting
Safe ® 500 can be cut either by abrasive waterjet, laser or plasma.

Bending
Safe® 500 offers ability to cold forming but as other protection steels must be used with caution. The elastic energy stored during forming may lead to rupture or shifting. It is essential to maintain a safety distance and not situate oneself in front of the plate while it is being formed. It is crucial to wear appropriate individual safety equipment and to equip machines with collective protection.
The capacity of the machine and tools must be suitable information on bending loads in relation to tools, plate thickness and steel strength.
The most important parameter when bending are the use of a correct punch radius. Please contact us if you need assistance.

General recommendations:

• Minimum recommended temperature: 15°C
• Make sure there are no obvious defects, especially at the edges. Ideally, the edges of the plate in the bending area should be sanded smooth and rounded before starting work.
• The edges of the die should remain clean, smooth and perfectly lubricated (CRC SP 350).
• Perform preliminary tests on prototypes and form the first parts, recommending a low speed.
• Make sure there is enough space in the die for the selected punch together with the workpiece:
• Die width > punch diameter + 3 x thickness

Welding

Safe ® 500 can be welded using common welding processes. Like the other protection steels, it can be sensitive to cold cracking in the heat affected zone of a weld. The best results can be obtained by :

• Ensure that the steel is at least at room temperature (≈20 °C)
• Clean the weld area by removing potential sources of hydrogen: rust, scale, moisture, grease, etc.
• Use low-hydrogen welding methods and consumables (hydrogen content in the HD filler material ≤ 5 ml/100 g).
• It is preferable to use MAG welding and a welding sequence designed to minimize residual stresses.
• Austenitic consumables must be used. Stainless austenitic consumables – type AWS 307 are recommended.

Delivery conditions

Heat treatment

Safe ® 500 is quenched and tempered at low temperature (≤ 200°C)

Surface properties

According to EN 10163 class B – subclass 3

Shot blasting and weldable primer application can be performed upon request.

Sizes and tolerances

Safe ® 500 is supplied as cut-to-length sheets (from hot strip mill).

Flatness

Maximum flatness deviation is 3 mm/m (when measured according to EN 10029).