Needle-Punched Carbon Preform for Binder-Free Friction Layers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for producing porous, carbon-containing preforms for carbon-ceramic brake discs result in a poor connection between the friction layer and the body, requiring the use of binders.
Innovation Solution
The process involves forming a body and friction layer using unidirectional and randomly-arranged carbon fiber fabrics through needle-punching, creating vertical cross-linked bonds without the need for binders, thereby enhancing the connection between the layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a binder is used to bond the friction layer to the body, then the connection strength is improved, but the manufacturing complexity and number of steps increase
Solution Approach 1:
The invention extracts and eliminates the binder from the manufacturing process. Instead of using a binder to bond the friction layer to the body, the patent uses a needle-punching process that mechanically interlocks the layers through fiber entanglement, thereby removing the binder step and simplifying the manufacturing process while maintaining connection strength
Solution Approach 2:
The invention replaces the chemical bonding mechanism (binder) with a mechanical bonding mechanism (needle-punching). The needle-punching process creates physical interlocking through barbs that carry fibers and create vertical cross-linked bonds, substituting the chemical adhesive system with a purely mechanical fastening system
2Manufacturing precision
If three separate steps are used to form body, friction layer, and bond them, then the manufacturing precision is improved, but the productivity decreases
Solution Approach 1:
The invention merges the bonding operation into the layer formation process itself. The needle-punching process that forms the friction layer simultaneously bonds it to the body, eliminating the need for a separate bonding step. This consolidation maintains manufacturing precision while significantly improving productivity by reducing the total number of operations
Solution Approach 2:
The invention performs the bonding action preliminarily during the friction layer formation process. Rather than forming layers and then bonding them in subsequent steps, the needle-punching process creates both the friction layer structure and the bonding connections in a single integrated operation, thereby improving production efficiency without sacrificing precision
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
This method ensures a strong and binder-free connection between the friction layer and the body, improving the structural integrity and performance of the carbon-ceramic brake discs.
Implementation Method 1
at penetration of a needle, barbs of the needle carry with them some fibers from each sheet which the needle penetrates. As a result, the fibers carried by the barbs create vertical cross-linked bonds between the sheets of the unidirectional carbon fiber fabric
Implementation Method 2
silicon is infiltrated into the green compact by the action of the capillary forces
Data Source
Figure 1~3(f)
Figure 4~5(i)
AI summary
There is provided a porous, carbon-containing preform, including a body (CL) of unidirectional carbon fiber fabrics (C1), and a friction layer (FL) of randomly-arranged-carbon-fiber fabrics (F1), combined with the body (CL) by a needle-punching operation. According to the present invention, it is by the needle-punching operation that the friction layer (FL) of the randomly-arranged-carbon fiber fabric (F1) is formed on the body (CL) of the unidirectional carbon fiber fabric (C1) and the friction layer (FL) of the randomly-arranged-carbon-fiber (F1) is cross-linked to the body (CL) of the unidirectional carbon fiber fabric (C1 ) in producing the porous, carbon-containing preform.