It is the substitution of asbestos friction material by metal friction material and the decreasing of structure mass that vary the structure dynamic stability and even worsen the problem of braking noise.

• 制动器结构中取代能排放有害物质的石棉摩擦材料的金属摩擦材料的应用以及结构的轻量化,都会不同程度地改变制动器结构的动态稳定性,甚至致使制动器振动噪声问题恶化。