Multi-Layer Tyre Tread Elastomer Blends for Wear and Heat Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tires designed for high-speed, long-distance travel face issues with wear, temperature rises, and puncture resistance, leading to premature degradation and reduced endurance, especially in heavy-duty vehicles.
Innovation Solution
A tire design featuring a crown reinforcement with two working layers oriented at angles between 8° and 45°, covered by a tread with two superimposed elastomeric layers, where the radially outer layer has a higher modulus of elasticity to enhance wear resistance and the central layer has lower hysteretic properties to manage temperature, combined with a specific angle configuration and elastomeric compound ratios to improve puncture resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single protective layer with uniform orientation is used in the crown reinforcement, then the structure is simple and easy to manufacture, but the tire exhibits poor resistance to shear stresses and temperature rises, leading to reduced endurance
Solution Approach 1:
The protective layer is divided into two distinct layers: a first protective layer with inextensible reinforcement elements oriented at angles between 45°-90° to the circumferential direction, and a second protective layer with elastic reinforcement elements oriented at angles between 10°-45° to the circumferential direction. This segmentation allows each layer to address specific stress types (transverse compression and shear stresses) independently, improving overall endurance without excessive complexity
Solution Approach 2:
The crown reinforcement combines two types of reinforcement elements with different mechanical properties: inextensible elements (metallic wires or cables) for resisting transverse compression forces, and elastic elements (extensible reinforcing elements) for accommodating shear stresses and temperature-induced deformations. This composite approach creates a more resilient structure that better withstands the complex stress environment
2Duration of action of moving object
If the tread is made of elastomeric materials with high wear resistance, then the tire lasts longer in terms of wear, but the temperature rise in the crown area increases, accelerating rubber degradation and reducing tire endurance
Solution Approach 1:
The tread is constructed with two layers of elastomeric compounds with different properties: an outer tread layer optimized for wear resistance and an inner tread layer with lower hysteresis to reduce heat generation. This local differentiation allows the tire to achieve both high wear life and acceptable temperature management, as the inner layer specifically addresses the thermal issue in the crown area while the outer layer provides the necessary wear resistance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The tire design achieves improved wear resistance, reduced rolling resistance, and enhanced puncture resistance, allowing for a longer service life and reduced risk of retreading, while maintaining satisfactory temperature management and endurance performance.
Implementation Method 1
the second elastomeric compound has a maximum value of tan(δ), denoted tan(δ)max, less than or equal to 0.30
Implementation Method 2
the first layer forming the radially outer part of the tread consists of a first elastomeric compound having a modulus of elasticity under tension at 10% elongation less than or equal to 10 MPa
Data Source
AI summary
The invention relates to a tyre, the tread (6) of which comprises at least two layers (61, 62) of elastomer blends. According to the invention, the two working crown layers (51, 52) are only present to form the crown reinforcement (5) over at least 80% of the width of the tread (6), the absolute value of the difference between the absolute values of the angles α2 and α1 being greater than 4°, α2 being greater than α1 in absolute terms, the mean angle α satisfying the relationship 14+131*exp(-L/100) < α < 20+164*exp(-L/100). According to the invention, the first layer (61) forming the radially exterior portion of the tread (6) is formed by a first elastomer blend, the elastic modulus of which in tensile stress at 10% elongation is less than or equal to 10 MPa, and the second layer (62) is formed by a central portion (621) and two axially exterior portions (622), wherein said central portion (621), which has a thickness greater than or equal to 1 + max(1.5*(p2- 1.5) + 11*(F2/FR2 - 0.14),0), is formed by a second elastomer blend having an elastic modulus in tensile stress at 10% elongation of greater than or equal to 15 MPa and a maximum tan(δ) value of less than or equal to 0.30, the axially exterior portions (622) being formed by a third elastomer blend having a maximum tan(δ) value of less than 0.15.