SiC-Reinforced Aluminum Brake Disc Material for High-Temperature Strength
Solution Overview
Problem
Existing aluminum matrix composite materials, such as SiCp/A356, suffer from softening and decreased braking performance at high temperatures, limiting their use in high-speed rail and automotive braking systems.
Innovation Solution
A high-strength, heat-resistant aluminum matrix composite material composed of specific elements (Cu, Mg, Ag, Mn, Ti, Zr) and SiC particles, with optimized preparation methods including melting, refining, and semi-solid stirring to ensure even distribution and bonding of SiC particles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If SiCp/A356 composite material is used for brake discs, then weight is reduced by 50%-60% and wear resistance is improved, but high-temperature resistance deteriorates causing softening at temperatures above 300°C
Solution Approach 1:
The patent changes the chemical composition parameters of the aluminum matrix by adding specific elements (Cu: 3-7%, Mg: 0.5-1.5%, Ag: 0.1-0.5%, Mn: 0.05-0.3%, Ti: 0.05-0.2%, Zr: 0.05-0.2%) to create a heat-resistant alloy system that maintains strength at elevated temperatures up to 400°C
Solution Approach 2:
The patent uses SiC particles (10-40 volume%) as reinforcing phase combined with the optimized aluminum matrix to create a composite material that achieves both high-temperature resistance and wear resistance, with tensile strength maintaining above 180 MPa at 300°C
2Ease of manufacture
If ordinary aluminum alloy is used for brake discs, then manufacturing is simple and cost is low, but high-temperature resistance is insufficient causing softening at 300°C-400°C
Solution Approach 1:
The patent modifies the aluminum alloy composition by adding multiple alloying elements within specific ranges to achieve heat resistance while maintaining castability and manufacturability through conventional casting processes
Solution Approach 2:
The patent creates local strengthening through precipitate phases formed by Cu, Mg, and Ag elements, and through SiC particle reinforcement, providing localized heat resistance without compromising overall manufacturability
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 composite material exhibits excellent high-temperature resistance and wear resistance, maintaining tensile strength above 180 MPa at 300°C and a stable friction coefficient, suitable for high-speed braking systems.
Implementation Method 1
the aluminum matrix composite material exhibits excellent high-temperature resistance and wear resistance, maintaining tensile strength above 180 MPa at 300°C
Implementation Method 2
a reinforcing phase, which is SiC particles with a volume percentage of 10%-40%
Data Source
AI summary
An aluminum-based composite material and a brake disc made of the composite material are provided. The material includes a base material and a reinforcing phase. The base material includes the following components in mass percentage: 4.0-7.0% of Cu, 0.4-1.2% of Mg, and 0.1-0.8% of Ag, with the balance being Al. The reinforcing phase can be SiC particles having a volume percentage of 10-40%.