The Quard abrasion resistant plates are delivered with hardness of 400 HB (Quard 400), 450 HB (Quard 450) and 500 HB (Quard 500), with thicknesses ranging from 3.2 mm to 64 mm and widths from 1,500 to 3,100 mm. They are designed for construction and mining equipments (excavators, dump trucks, bulldozers, hoppers, mixers, etc.), as well as for machinery in very demand industries (recycling, agriculture,etc). The use of Quard may result in product lifetime being more than tripled when compared to products made from standard grades of steel.
Quard is a martensitic abrasion resistant steel with an average hardness of 400, 450 and 500 HBW. Due to its versatility in terms of high toughness, good cold formability and excellent weldability, Quard combines outstanding workshop performance and long lasting wear resistance.
Quard is recommended for the following applications:
The following Quard product mix is currently available:
| Thickness mm | Width mm | |
|---|---|---|
| Quard 400 | 4-50 mm | |
| Quard 450 | 4-64 mm | 1,500–3,100 mm |
| Quard 500 | 4-40 mm |
Hardness guarantee
| Hardness | |
|---|---|
| Quard 400 | HBW = 370–430 |
| Quard 450 | HBW = 420–480 |
| Quard 500 | HBW = 470–530 |
Brinell hardness test, HBW according to EN ISO 6506-1, is performed 1–2 mm below the plate surface once per heat and 40 tonnes.
Hardness guarantee
| V-notch impact test (longitudinal at –40°C) | Yield strength (MPa) | Tensile strength Transverse testing (MPa) | Elongation A5 (%) | |
|---|---|---|---|---|
| Quard 400 | 40 J | 1,160 | 1,300 | 10 |
| Quard 450 | 35 J | 1,250 | 1,400 | 10 |
| Quard 500 | 30 J | 1,500 | 1,700 | 8 |
Steel is grain refined
| Laddle Analysis,%max | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Plate Thickness | C | Si | Mn | P | S | Cr | Ni | Mo | B | |
| 4-25.4 mm | 0.16 | 0.60 | 1.40 | 0.025 | 0.010 | 0.50 | 0.10 | 0.25 | 0.005 | |
| 25.41–40 mm | 0.17 | 0.60 | 1.60 | 0.025 | 0.010 | 1.15 | 0.10 | 0.30 | 0.005 | |
| 40.01–50 mm | 0.17 | 0.60 | 1.60 | 0.025 | 0.010 | 1.30 | 0.50 | 0.50 | 0.005 | |
| Laddle Analysis,%max | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Plate Thickness | C | Si | Mn | P | S | Cr | Ni | Mo | B | |
| 3.2–20 mm | 0.20 | 0.60 | 1.40 | 0.025 | 0.010 | 0.20 | 0.10 | 0.25 | 0.005 | |
| 20.1–40 mm | 0.21 | 0.60 | 1.60 | 0.025 | 0.010 | 0.75 | 0.10 | 0.30 | 0.005 | |
| 40.01–64 mm | 0.23 | 0.60 | 1.60 | 0.025 | 0.010 | 1.30 | 0.50 | 0.50 | 0.005 | |
| Laddle Analysis,%max | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Plate Thickness | C | Si | Mn | P | S | Cr | Ni | Mo | B | |
| 4–40 mm | 0.30 | 0.80 | 1.60 | 0.025 | 0.010 | 1.00 | 1.00 | 0.50 | 0.005 | |
| Carbon equivalent, typical values, % | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Plate Thickness | CEV (1) | CET (2) | |||||||||
| Quard 400 | 4–8 mm | 0.36 | 0.25 | ||||||||
| 8.01–20 mm | 0.40 | 0.28 | |||||||||
| 20.01–25.4 mm | 0.45 | 0.29 | |||||||||
| 25.41–40 mm | 0.57 | 0.33 | |||||||||
| 40.01–50 mm | 0.64 | 0.36 | |||||||||
| Quard 450 | 3.2–7.99 mm | 0.41 | 0.30 | ||||||||
| 8–20 mm | 0.41 | 0.32 | |||||||||
| 20.01–40 mm | 0.56 | 0.37 | |||||||||
| 40.01–64 mm | 0.64 | 0.40 | |||||||||
| Quard 500 | 4–20 mm | 0.57 | 0.40 | ||||||||
| 20.01–40 mm | 0.61 | 0.43 | |||||||||
Quard offers a unique combination of excellent flatness, tight thickness tolerances and superior surface finish.
| Grade | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Feature | Quard 400 | Quard 450 | Quard 500 | |||||||
| Flatness | EN 10029: class N (standard) and class S | |||||||||
| Thickness tolerance | Meet and exceed EN 10029 Tighter tolerances upon request |
|||||||||
| Shape, length, width and thickness tolerances | Comply with EN 10029 | |||||||||
| Surface properties | Exceed existing market standards EN 10163-2 Class B3 | |||||||||
Quard 400, Quard 450 and Quard 500 receive their properties through quenching and when applicable with subsequent tempering. For these properties to be retained, Quard plates should not be used in applications requiring heat treatment and service temperatures above 250°C. Quard 400, Quard 450 and Quard 500 is not intended for any additional heat treatment.
Ultrasonic testing (UT) is used to identify such discontinuities as inclusions, cracks and porosity. In thickness from 8 mm and higher, all plates are UT tested and controlled against class S2, E2 in accordance with EN10160.
To obtain optimal processing productivity for Quard 400, Quard 450 and Quard 500, it is essential to use the recommended procedures and tools given below
Plasma and flame cutting can be performed without the need for preheating plates in thicknesses up to 20 mm, provided the ambient temperature is above 0°C. After cutting, plates should be cooled down to room temperature. Slow cooling reduces the risk of cut edge cracking. Never use accelerated cooling
Quard grades are well suited for cold forming. The minimum recommended R/t ratios for Quard bending are given in the table below:
| Carbon equivalent, typical values, % | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Thickness (mm) | Transverse to rolling (R/t) | Longitudinal to rolling (R/t) | Trans. width (W/t) | Long. width (W/t) | |||||||
| Quard 400 | t < 8.0 | 2.5 | 3.0 | 8 | 10 | ||||||
| 8 ≤ t < 20 | 3.0 | 4.0 | 10 | 10 | |||||||
| t ≥ 20.0 | 4.5 | 5.0 | 12 | 12 | |||||||
| Quard 450 | t < 8.0 | 3.5 | 4.0 | 10 | 10 | ||||||
| 8 ≤ t < 20 | 4.0 | 5.0 | 10 | 12 | |||||||
| t ≥ 20.0 | 5.0 | 6.0 | 10 | 12 | |||||||
| Quard 500 | t < 8.0 | 3.5 | 4.5 | 10 | 12 | ||||||
| 8 ≤ t < 20 | 4.5 | 5.0 | 12 | 14 | |||||||
| t ≥ 20.0 | 6.0 | 7.0 | 16 | 18 | |||||||
Quard shows good weldability due to low carbon equivalent. It can be welded using any conventional welding method,both manual and automatic. Quard welding is recommended at ambient temperatures not lower tan +5°С.
After welding, the welded parts should be left to cool down to room temperature. Never use accelerated cooling.When welding plates in thicknesses up to 12 mm using a heat input of 1.7 kJ/mm, preheating is not required. Interpass temperatures used should not exceed 225˚C. Soft weld consumables, ensuring low hydrogen weld deposits (<= 5 ml/100g), are recommended to avoid hydrogen cracking. The consumable strength should be as soft as the design and wear mode allows..
In general, welding recommendations for Quard plates should comply with EN-1011.
Quard offers good machinability with HSS and HSS-Co alloyed drills. The feed rate and cutting speed have to be adjusted to the high hardness of the material. Face milling, counter boring and countersinking are best performed using tools with replaceable cemented carbide inserts.