Xar400 Nm400 Ar400 Wnm400 Hardface Heat Wear Resistant Plate

XAR400 wear sheet / XAR400 / XAR450 / XAR500 PLATE

This Material Specification applies to 3 to 100 mm (0.118 to 3.937 in.) thick plates of the wear-resistant special  structural steel XAR® 400.

Application

The steel may be used at the discretion of the purchaser for wear-exposed structures, e.g. excavating, mining and  earth-moving  machinery,  truck  dump  bodies,  conveying,  crushing  and  pulverizing  equipment,  scrap  presses,  paving moulds and in switch manufacturing.

The processing and application techniques as a whole are of fundamental importance for the successful use of the  products fabricated of this steel. The processor/fabricator must assure himself, that his design and work methods  are appropriate for the material, are state-of-the-art and are suitable for the envisaged purpose.

The selection of the material is left up to the purchaser.

Chemicalcomposition (heat analysis, mass.-%)

The steel has a fine-grained microstructure. Nitrogen is absorbed to form nitrides by means of Al and, where  applicable, Nb or Ti.

Delivery condition:  quenched or quenched and tempered (see paragraph "Heat treatment").

Mechanical properties

Hardness at room temperature  in the delivery condition:  370 - 430 HBW

The Brinell hardness shall be determined in accordance with DIN EN ISO 6506. The hardness shall be measured  roughly 1 mm (0.039 in.) below the surface of the plate.

Plate thicknesses up to 35 mm (1.378 in.) will also feature a core hardness ≥ 90 % of the minimum hardness. 

Typical carbone quivalent and strength values, typical of 15mm(0.591in.) plate thickness  

Carbon equivalent CET in %  [CET = C + (Mn + Mo) / 10 + (Cr + Cu) / 20 + Ni / 40]    : 0.32 
Carbon equivalent CE in %    [CE = C + Mn / 6 + (Cr + Mo + V) / 5 + (Ni + Cu) / 15]    : 0.51  
Yield strength in MPa (ksi) *)                : 1000 (145.0) 
Tensile strength in MPa (ksi) *)               : 1250 (181.3) 

Elongation at fracture A in %         : 10

Impact energy for plates up to 35 mm (1.378 in.) thickness at - 20 °C (- 4 °F) in the state of delivery condition:   min. 27J (20 ft lbf) (transverse)

The testing is performed according to ISO 148-1.The values stated for the impact energy are minimum values  obtained as the average of 3 specimens, no single value being less than 70 % of the minimum value. 

The specimens are taken near the surface. For thicknesses < 10 mm (< 0.394 in.) the impact energy value is  reduced proportionally to the specimen width (product thickness). For nominal thicknesses < 6 mm (0.236 in.) the  impact energy will also be testified.

In case of need of plate thicknesses above 35 mm with minimum core hardness and/or minimum impact energy,  we optionally offer our XAR 400 PREMIUM (Material specification 713). 

Numberoftests

Unless  otherwise  agreed  upon  in  the  order,  the  tests  listed  below  will  be  performed  during  the  acceptance  inspection:

Up to 35mm (1.378in.) thickness:   

1 notched-bar impact test (1 set = 3 specimens)     
per 40 t per heat  
1 determination Brinell hardness  
 Over 35mm (1.378in.) thickness:   
1 determination Brinell hardness  per heat
General processing information

For those who process these steels for the first time, it is recommended to consult the steel supplier to take  advantage of the experiences gathered so far.

The general information stated below can only cover a few of the important points. The recommendations given in  STAHL-EISEN-Werkstoffblatt 088 (Weldable fine-grained structural steels, guidelines for processing, in particular  for welding) correspondingly apply to this steel as well.

Recommendations  for  welding  are  also  given  in  EN  1011  part  1  and  part  2  -  Welding,  Recommendation  for  welding of metallic materials -.

It is left to the discretion of the processor/fabricator to decide which of the familiar precautions must be adopted to  avoid cracking during thermal cutting and welding under the prevailing construction and fabrication conditions.

Cold forming

The products made of this steel are suitable for cold bending provided, that consideration is given to the high  hardness. The formability of steel decreases with increasing hardness. This has to be kept in mind when forming.  The forming must take place at a slow and steady rate, the cut edges must be deburred and the plates heated, if  necessary, prior to the forming. A final stress-relieving is not considered for this steel.

Machinability

In spite of its high wear resistance, the steel exhibits good machinability if sufficiently heavy machine-tools and  sharp carbide-tipped tools are used. The feed rate and cutting speed have to be adjusted to the high hardness of  the material.

Heat treatment

Plates of the XAR® 400 grade receive the required properties as a result of austenitizing and follow-on quenching  in special facilities and, where applicable, tempering below Ac1. Direct quenching after hot-rolling is considered  equivalent to conventional quenching. The heat treatment depends on the chemical composition and the product  thickness. To avoid hardness losses, the steel must not be heated above 250 °C (482 °F).

Thermal cutting

Preferably the flame-cutting process is used. For small product thicknesses, however, the plasma cutting process  is used in the interest of minimum distortion.

Preheating is not normally necessary when flame-cutting thicknesses up to around 30 mm (1.181 in.). However, if  the workpiece temperature is below + 5 °C (+ 41 °F), or the cut edges are to be cold-formed in the course of  further processing, preheating to about 150 °C (302 °F)  should be considered in the  interest of cold cracking  resistance.

Welding

If  due  consideration  is  given  to  the  general  rules  for  welding,  this  steel  is  weldable  both  manually  and  automatically. To prevent cold cracking in the welded joints only welding consumables giving welds of very low  hydrogen content should be used.

Preheating is not generally necessary for welding with austenitic filler metals.

For  highly  stressed  weld  seams,  welded  with  ferritic  filler  metals,  preheating  should  in  general  be  used  for  thicknesses stated in STAHL-EISEN-Werkstoffblatt 088. The preheat temperature level for welding depends on the  plate  thickness and the  residual stress state of  the structure. The working  temperature should  not go  beyond  250 °C (482 °F).

The wear resistance of components fabricated of XAR® 400 may be increased with the aid of wear resistant layers  deposited by means of welding or metal spraying.

Genera linformation

Unless otherwise agreed upon in the order, the delivery will be governed by the conditions outlined in EN 10021.

The admissible tolerances are based on EN 10051 for plates cut from hot strip and EN 10029 for four-high mill  plates, unless other terms have been agreed upon.

The plates will be supplied  with a  maximum flatness tolerance according  to  EN  10029, table 4, steel type H. 
Smaller flatness tolerances can be agreed upon at the time of ordering.

For surface quality requirements EN 10163 is applicable. 

As per special agreement it is possible to supply plates descaled or descaled and primed.