How Hardness Testing Ensures Wear Resistance in Twin Screw Extruder Barrels

In twin screw extrusion processes, barrel wear is one of the most critical factors affecting equipment stability, service life, and operating cost.
Especially under high load, high filler, or abrasive material conditions, insufficient wear resistance can lead to rapid clearance increase, process instability, and premature barrel failure.

At ZHITIAN, barrel wear performance is not treated as a single parameter issue, but as the result of alloy material design, manufacturing process, and quality inspection working together.

ZHITIAN operates a dedicated alloy material R&D department, focusing on wear-resistant and corrosion-resistant solutions for twin screw extruder barrels.

After the integral alloy liner of a twin screw barrel is manufactured, it does not enter delivery directly.
Instead, it goes through a series of inspections, including:

• Chemical composition verification
• Microstructure evaluation
• Dimensional inspection
• Hardness testing, which plays a key role in wear performance assessment

Among these, hardness testing is often the most discussed — and also the most misunderstood — indicator.

Hardness reflects a material’s resistance to plastic deformation under localized force.
In abrasive extrusion conditions, harder surfaces generally resist:

• Cutting and plowing by fillers
• Micro-grooving caused by solid particles
• Surface deformation under repeated contact

From this perspective, higher hardness usually improves abrasive wear resistance, which is why hardness testing is a standard inspection step for alloy-lined barrels.

However, hardness alone does not fully define wear performance.

In real extrusion applications, barrel wear is rarely caused by pure abrasion alone.
It often involves a combination of:

• Abrasive wear
• Adhesive wear
• Fatigue wear
• Corrosive wear

If hardness is increased without proper alloy design and process control, excessive hardness may result in:

• Reduced toughness
• Higher risk of cracking or chipping
• Poor resistance to impact and thermal cycling

Therefore, the goal of ZHITIAN’s alloy development is not maximum hardness, but a balanced hardness range combined with stable microstructure and strong matrix support.

For each integral alloy-lined twin screw barrel, hardness testing is applied as:

• A verification of alloy consistency
• A confirmation of process stability
• An indirect indicator of wear resistance reliability

Hardness values are evaluated together with material composition and process parameters, not in isolation.
This ensures that the barrel liner maintains both wear resistance and structural reliability during long-term extrusion operation.

This case demonstrates that in twin screw extruder barrels:

• Hardness is an important foundation for wear resistance
• Wear performance depends on material system design, not a single number
• Stable service life comes from controlled alloy development, manufacturing, and inspection

By integrating alloy R&D, production, and testing, ZHITIAN ensures that hardness testing becomes a meaningful engineering indicator, rather than a superficial specification.

ZHITIAN specializes in twin screw extruder barrels, gearboxes, shafts, and screw elements, with strong capabilities in alloy material research, integral liner manufacturing, and wear-resistant solutions.

Through continuous material innovation and process optimization, ZHITIAN provides extrusion components designed for long-term stability, predictable wear behavior, and real operating conditions.