Wear as a System Behaviour
Wear is the progressive loss of material from a working surface in relative motion against another body or a stream of particles. It is not a material constant: the same plate can outlast a harder alternative in one chute and fail quickly in another, because the wear rate depends on the whole tribological system. That system includes the counter-material, the load, the sliding speed, the movement mode, the lubrication state, the environment and the temperature, as well as the composition, microstructure, hardness and surface condition of the steel itself.
Practical wear assessment therefore starts with the equipment and the material being handled. Once the dominant mechanism is identified, the plate specification follows: hardness for sliding abrasion, toughness for impact, low-carbon and low-sulphur chemistry for corrosive or hydrogen-bearing service, and geometry and thickness for high-angle erosion.
Mechanisms and Their Causes
Abrasive wear occurs when hard particles or a rough counterface cut, plough or gouge the surface. Its severity rises with particle hardness relative to the surface hardness, with particle angularity rather than roundness, with contact pressure and with the number of particles passing per unit time.
Adhesive wear occurs when asperities in sliding contact weld together and are then torn off, transferring material from one surface to the other. It is driven by high local contact pressure, insufficient lubrication, an unsuitable material pair and a rough surface finish.
Corrosion wear occurs when chemical or electrochemical attack removes or embrittles the surface layer, so mechanical action then removes fresh metal underneath. Moisture, dissolved salts, acidic or alkaline process streams and elevated temperature accelerate it.
Erosion wear is caused by a stream of solid particles or a fluid carrying particles striking the surface. Its character changes with impact angle: shallow angles act like cutting, while steep angles produce repeated deformation and crack formation.
Contact fatigue wear is caused by cyclic loading of a rolling or sliding contact, which generates subsurface shear stresses and cracks that eventually spall material from the surface, as seen on crusher rolls and heavily loaded rail-adjacent components.
Fretting wear arises from small-amplitude oscillatory movement between clamped surfaces, breaking down the surface film and generating oxide debris that then acts as an abrasive.
Operating Factors That Change the Wear Rate
| Factor | Effect on wear |
|---|---|
| Load and contact pressure | Higher pressure increases penetration of abrasive particles and promotes adhesive welding |
| Sliding speed | Raises surface temperature, changes the oxidation regime and increases material removal per unit distance |
| Particle hardness and angularity | Sharp, hard particles remove far more material than rounded, soft ones of the same size |
| Particle size and feed rate | Larger particles and higher throughput increase the number and depth of cutting events |
| Impact angle and energy | Steep angles shift the mechanism from cutting to deformation and cracking, favouring toughness over hardness |
| Moisture and chemistry | Wet, saline or acidic conditions add corrosion to mechanical loss |
| Temperature | Elevated temperature softens the steel and accelerates oxidation; low temperature reduces toughness |
| Surface finish and geometry | Roughness, sharp transitions and weld spatter act as stress raisers and initiate wear and cracking |
Because these factors interact, a change in any single item can alter not only the wear rate but the mechanism itself. Increasing throughput in a chute may convert a mild sliding wear situation into a combined sliding and erosion problem, at which point a harder plate alone will not deliver the expected life extension.
Matching the Steel to the Cause
Once the mechanism is understood, the plate can be selected on the property that actually controls the damage. Where fine abrasive sliding dominates, the surface hardness of the quenched and tempered wear plate family covered by GB/T 24186 is the leading parameter, and wear resistance improves as hardness approaches and exceeds the hardness of the abrasive. Where impact dominates, thickness, support geometry and toughness matter more, and a slightly lower hardness grade with a controlled impact energy is the safer choice. Where corrosion contributes, a lower carbon and sulphur content with good weldability is preferable, and where erosion at a steep angle is present, the shape of the chute and the use of deflectors reduce the incident angle before any material change is made.
Laboratory guidance comes from standardised abrasion tests such as the dry sand rubber wheel method of ASTM G65 and the wet abrasion method of ASTM G105, supported by Brinell hardness measurement to GB/T 231.1. These tests rank materials under a defined set of conditions; they do not replace a site trial, but they eliminate clearly unsuitable candidates before a trial is designed.
Quality Control and Practical Measures
Reducing wear is usually cheaper than replacing plate more often. Practical measures include smoothing material flow paths, avoiding ledges and dead zones where material accumulates, keeping discharge angles steep enough that material slides rather than builds up, installing removable liners so that worn areas can be replaced without cutting structural steel, and monitoring thickness at fixed points so that replacement is planned into a maintenance window instead of forced by a failure.
For the incoming material, verification of the grade, hardness range, thickness and surface condition, together with a traceable inspection certificate to EN 10204, prevents a soft or misidentified plate from entering a critical wear zone. The welding procedure also matters: excess heat input tempers the martensitic surface beside the weld and creates a soft band that wears faster than the surrounding plate, so preheat, heat input and interpass temperature limits belong in the procedure as a wear-life requirement, not only as a cracking precaution.
Frequently Asked Questions
Q: What is the main cause of wear in abrasion resistant steel plate?
A: Abrasive wear caused by hard particles cutting the surface, which dominates in chutes, hoppers, buckets and bulk handling equipment.
Q: Why does the same plate wear at different rates in different locations?
A: Because wear depends on the whole system, including load, speed, particle hardness and shape, moisture and impact angle, all of which vary between locations.
Q: How does moisture affect wear?
A: Water accelerates loss through corrosion and by transporting abrasive particles, so wet service often needs a different grade or a corrosion-resistant overlay.
Q: Does higher hardness always reduce wear?
A: Only where sliding abrasion dominates. Under heavy impact, excessive hardness increases the risk of cracking and spalling, which can shorten life.
Q: How can wear be reduced without changing the material?
A: By improving flow geometry, removing ledges, increasing discharge angles, using removable liners and monitoring thickness so that replacement is planned.
Q: Which standards support wear assessment?
A: GB/T 24186 for wear resistant steel grades and hardness, GB/T 231.1 for Brinell testing, and ASTM G65 and ASTM G105 for controlled abrasive wear testing.
