DESCRIPTION

Wear resistance:

More than hardness, the wear resistance of CREUSABRO 4800 is based on:

• a very fine distribution of chromium, molybdenum, and titanium microcarbides reinforcing the microstructure with the same principal as composite materials.

• a very efficient work hardening capacity in service, coming from a metallurgic effect called "TRIP effect"  (TR ansformation Induced by Plasticity).            

• Reinforcement of the grain structure with titanium carbides.                                                                                                                                                     

Together with its high wear properties, CREUSABRO 4800 exhibits very good aptitude to processing. Especially, the limited hardness in delivery condition, strongly facilitates processing operations like cutting, machining and forming.

Controlled as delivered hardness range:

Minimum 340HB, Typical 400HB.

High toughness and impact resistance:

CHARPY V long at -20^oC  > 30 J/cm² 

Typical value at -20^oC : 45 J/cm2 

Tensile strength - typical values at 20^oC-:

Ultimate tensile     =     1 200 MPa

Yield strength        =     900   MPa

Elongation (5d)      =     12%

"TRIP effect": Transformation Induced by Plasticity 

 CREUSABRO 4800, due to its initial structure containing retained austenite, has the capability to work-harden in service under the action of local plastic deformations. 

These plastic deformations create a hardening effect by transformation of retained austenite into very hard fresh martensite. TRIP effect also contributes to the delay of chip removal from the steel under the action of abrasive particles. particles. The steel consequently becomes harder and remains resistant to wear by chip removal.

Fine dispersion of micro carbides

The fine structure of CREUSABRO 4800 is obtained by a fine dispersion of micro carbides. This structure is just the opposite of the rough acicular lamellar structure typical of 400HB water quenched Steels. water quenched steel, cracking along lamellas leads easily to the chip removal effect under the action of abrasion.

Titanium Carbides

In addition to the fine and homogeneous distribution of chromium and molybdenum carbides (respectively 1500 HV and 1800 HV) common to CREUSABRO steels. Creusabro 4800 is a new generation steel in the field of wear resistance steels with a significant addition of Titanium resulting in the formation of structure with very hard and fine particulars of titanium carbide, TiC reaching a hardness level of 3200Hv. These carbides give to the steel an increased wear resistance.

Delay of chip removal

Creusabro 4800 has the advantage of a higher capacity for plastic deformation caused by impacts. This extra-ductility induces a delay in the chip removal ensuring a slower wear rate (weight loss) than on 400HB water quenched steels.

This effect is strongly reduced in CREUSABRO 4800 which does not have this lamellar structure. More over, this fine dispersion of carbides reinforces the steel and works in combination with the work hardening effect to delay chip removal in service.

PROPERTIES AT HIGH TEMPERATURE

Chemical analysis of CREUSABRO 4800, specifically its chromium and molybdenum contents, imparts a high softening resistance in hot conditions, much better than that of 400HB water quenched steel.

This property allows processing of the steel in hot conditions (450/500˚C), hot forming for example, and cooling down in air without inducing any significant drop of hardness. The hot resistance of CREUSABRO 4800 allows its use in hot environments where pieces are heated up to 350˚C max.

SERVICE LIFE 

CREUSABRO 4800 metallurgical concept improves its wear resistance compared to other anti-abrasion grades available in the market, and in all service conditions. CREUSABRO 4800 benefits from the optimum compromise between wear resistance and ease of processing.

 APPLICATIONS                                                                                                                                                                                                                                 

CREUSABRO 4800 is intended for applications requiring extreme wear and impact resistance:
Mines, Quarries, cement industries, steel making, public works - It can be used in all environments, sliding, impact abrasion, in dry,  wet or hot conditions (350˚C max).

Quarries - Public Works 

Blades, bucket liners, chute plate liners, crusher lateral armouring, screens, dumper bodies, trommels

Mines 

Extraction equipment, conveyor bottom plates, hoppers, helical gravity and screw conveyors, skips, ventilators, discharge plates

Cement plants

Wheel excavator buckets, crusher lateral shields, clinker chutes, buckets, ventilators, dust separators, bagging machines  

Steel  plants

Guiding plates, hoppers, chutes, discharge plates, scrap containers / charging boxes.

DIMENSIONAL PROGRAM

Thicknesses 5mm to 100 mm

Standard Sizes: 1500 x 3000 mm

                          2000 x 6000 mm

                          2500 x 7500 mm (Other sizes available on request)

PROCESSING

Cutting

All classical  thermal processes (gas-plasma-laser) can be used.  Plasma/ Laser processes are especially recommended. They provide better precision and cutting aspects and induce a thinner Heat Affected zine (HAZ).

Whatever process (thermal) is used, the following conditions are sufficient to avoid cold cracking.

Water jet cutting can be used.

Machining

In accordance with standard procedures, with well maintained equipment with sufficient power. Drilling and milling operations can be done by utilising Sandvik Coromant drills and inserts.

with over carburized cobalt alloyed high speed tools of HSSCO type (examples : type AISI M42) with taper shank, long helical and as short as possible bits.
Lubrication by soluble oils diluted to 20%.
In case of deep or numerous drilling, we recommend the use of drills with tip in tungsten carbide or solid carbide bits (example : type ISO carbide quality K10  or K20), carbide tipped drills with TiN layer is especially suitable.

Indicative Parameters.

Forming

Cold forming can be done as long as the following conditions are met:

• edge preparation by grinding to remove flame cutting notches and nicks.

• minimum internal bending radius (table below)

• plate temperature at 10˚C minimum

According to the above parameters, bending strength depends on bending length, piece thickness, die opening..

Above table gives indicative power needed to bend for a die opening of 12 times the thickness.

Rolling

Shall be performed in following conditions. Øi > 30th (temperature of the piece > 10˚C)

CREUSABRO 4800 can be formed at a temperature of 450/500˚C without any further heat treatment. At this temperature, forming requires lower power than at room temperature, proportionally to the reduction of its yield strength YS 0,2.

WELDING

CREUSABRO 4800 can be welded with all conventional SMAW, GMAW, GTAW, SAW etc.

For welds non subjected to wear, following welding products can be used.

For welds subjected to wear, ask us for the best choice of welding consumables.

Welded areas should be clean, free of grease, water, oxides,...

Electrodes and flux shall be stoved according to supplier's recommendations.

Following preheating conditions shall be respected (for welded structure without excessive stresses).