How To Choose Wear-resistant Plastics

August 07, 2024

How to choose wear-resistant plastics, how to rank the top ten wear-resistant engineering plastics?

In the field of materials science and engineering, CoF usually refers to Coefficient of Friction. The Coefficient of Friction is a dimensionless value that describes the amount of friction between two contacting surfaces. It is a key parameter in the interaction of material surfaces and is important for understanding the sliding behavior of materials.

Among them:

Friction is the force that prevents two surfaces from sliding relative to each other.

Positive pressure is the force acting perpendicularly between two contacting surfaces.

Solid materials lubrication trio graphite, molybdenum disulfide, PTFE! These three materials have extremely low CoF. Any engineering plastics high wear-resistant modification, can not bypass the above three chivalrous marriage.

CoF=Friction / Positive Pressure

This article will discuss: PTFE, UHMWPE, PEEK, PI , POM, POK, Pa66, PA46, PPS, LCP ten typical wear-resistant plastics applications, wear-resistant there is no absolute strength and weakness：

About plastic wear resistance: first of all, we should consider the plastic working environment, such as running speed, frequency, friction of the object, the work of the load force situation, temperature and many other factors to consider, and then according to the needs of the selection of suitable materials. Practical applications, in the above working conditions, performance direction are determined, and then select the material, but often use composite modified engineering plastics, targeted, wear-resistant adaptability of economic materials.

Engineered Mortar Pipes Abrasion Resistance Application Testing

Conclusion: There is no absolute most wear-resistant plastic! PTFE in the face of the lowest coefficient of friction CoF mortar pipe applications, directly by the UHMWPE seconds, not even as good as PA66! PTFE in the and their own against the grinding is ta's highlights, at the moment the cement mortar will not be spoiled ta!

Obviously low coefficient of friction alone, and can not determine the actual application of plastic wear resistance, is not subverted your perception?

What are the factors that influence abrasion resistance and wear rate?

What are the dimensions needed to determine the abrasion resistance of plastics?

Contact type

Dynamic contact, e.g. sliding and rolling

Combination of mating surfaces, e.g. metal-to-metal, plastic-to-plastic, metal-to-plastic

Material or roughness of mating surfaces

Clearance of the mating surfaces

Environmental conditions

Temperature, including heat generated by friction

Exposure to sunlight

Moisture or contact with cosmetics

State and type of lubrication

Load

Pressure of externally applied load

Dynamic speed of motion

Evaluating the wear resistance of plastics involves a number of dimensions that can help us get a comprehensive picture of how a material will perform under different conditions. How do I choose a wear-resistant plastic?

Judge from the following 7 main dimensions:

1. Material properties:

Hardness: Plastics with high hardness are usually more wear-resistant, such as POM, PEEK and PI.

Crystallinity: Plastics with high crystallinity are usually more wear-resistant, such as PA66, POK, PEEK, etc.

Molecular weight: Higher molecular weight plastics typically have better abrasion resistance, such as UHMWPE.

Molecular weight distribution: Tight molecular arrangement and narrow molecular weight distribution can improve the wear resistance of materials such as POK, PPS, LCP, PEI, PEEK, etc.

Chemical composition: Plastics containing special groups (e.g. benzene rings) may affect wear resistance. Such as PPS, LCP, PEEK, PI.

PEEK Wear Resistant High Temperature Gear Applications

2. Physical Properties:

Coefficient of Friction (CoF): A lower coefficient of friction usually means that the plastic produces less friction on the contact surfaces, thus reducing wear and tear, such as PTFE and fluoroplastics for the whole family, UPE, POM, PA66, PA46, PEEK and so on.

Tensile Strength: Higher tensile strength means the material is less likely to break when subjected to stress.

Modulus of elasticity: Materials with a high modulus of elasticity deform less when subjected to external forces, helping to reduce wear.

Creep Behavior: The creep properties of a material under sustained load affect its wear resistance.

The above three points in the strength, modulus high, special engineering plastics have an absolute advantage, such as PPS, LCP, PEEK, PEI, PI and so on.

3. Environmental factors:

Temperature: the abrasion resistance of materials at different temperatures will change.

Humidity: Humidity affects the water absorption and expansion of materials, such as nylon, thus affecting the abrasion resistance.

Chemical medium: certain chemicals may accelerate the wear of the material.

According to the requirements of wear resistance of plastic parts, Plastic Junction lists the four most important points to consider, temperature resistance, chemical resistance, coefficient of friction, mechanical strength, in addition to the following:

4.Processing conditions:

Surface treatment: Surface coating or treatment can significantly improve wear resistance, such as PTFE is often used as a coating to provide wear resistance.

Molding methods: different molding methods (such as injection molding, extrusion, die casting, CNC, spraying, etc.) may affect the microstructure of the material, which in turn affects the wear resistance, in addition to the economy of processing must be considered, such as PTFE, UPE, PI is not suitable for injection molding, PEEK requires extremely high processing temperature.

Modifiers: Adding fillers, fibers and other modifiers can improve wear resistance, modification.

5.Test Method:

Sliding wear test: wear resistance is evaluated by simulating sliding wear in real applications.

Sandpaper abrasion test: Abrasion test using different numbers of sandpaper.

Wear Tester Test: Simulates wear under specific conditions using a specific wear tester.

Rolling Wear Test: Tested using a standard rolling ball wear tester.

Taber Abrasion Test: Standardized abrasion test using a Taber abrasion tester.

Coefficient of Friction Test: Evaluates wear resistance by measuring the coefficient of friction between a material's surface and other materials.

In short, different wear test methods, corresponding wear-resistant raw materials or modified plastics are used depending on the working conditions! If you have to wear against hardware, you need to increase the strength and fatigue resistance of the material, and improve the lubricity of the plastic and rubber parts. Considering the wear-resistant noise, improve the lubricity of wear-resistant materials and their elasticity.

6. Application environment:

Load conditions: different loads under the material wear resistance performance is different.

Contact material: the type of material in contact with the plastic will also affect the wear resistance.

Motion type: different types of motion such as sliding and rolling have different requirements for wear resistance.

Fluoroplastic chemical piping, and transmissi

Plastic parts inside the gearbox need to be oil resistant and mechanically strong

7. Long-term performance:

Aging performance: long-term exposure to specific environments (such as ultraviolet light, temperature cycling, etc.) will affect the wear resistance of the material, such as PEEK, PTFE, UPE, etc. have extremely excellent weathering and aging resistance.

Fatigue life: the durability of the material under repeated stress, such as UPE, POK, PEEK, PI and so on.

The above is the choice of wear-resistant plastic 7 dimensions! Wear-resistant plastics, there is no absolute strongest ranking.

Summarizing

PTFE and UHMWPE are the best performers in terms of coefficient of friction and self-lubrication, but with lower mechanical strength and extremely high wear resistance requirements first! But it also depends on the object of friction.

POM is excellent in terms of wear resistance and self-lubrication, very cost-effective and suitable for most gear and transmission applications.

PA66 is excellent in wear resistance and self-lubrication, moderately priced, wear modified to cover the widest range of applications.

PEEK, PI has high wear resistance, weather resistance, heat resistance and chemical resistance, suitable for working conditions appear temperature 300 + applications, but the cost is very high.

POK, excellent performance in wear resistance and lubrication, a combination of PA + POM performance, moderate cost, but the processing temperature is narrow, the application is limited.

LCP, PPS, PA46 has excellent mechanical properties and heat resistance, heat resistance 250-290 wear-resistant applications can not bypass the choice, but the cost is high.

Through the comprehensive consideration of these dimensions, you can more comprehensively assess the wear resistance requirements of plastics. In practical applications, the most suitable material needs to be selected according to the specific use environment and working conditions. If you need more detailed data to support the decision, you can refer to the relevant test standards and material properties and product manuals to do testing before making a decision.

Author:

Ms. Tina

E-mail:

sales@honyplastic.com

Phone/WhatsApp:

+8618680371609