Why Magnesium Oxide Is a High-Performance Functional Filler for Brake Pads

In the friction material formulation system of automotive brake pads, Magnesium Oxide is an inorganic functional filler with excellent performance. It is widely used in semi-metallic, ceramic-based and non-asbestos organic (NAO) brake pads, and is a core additive balancing braking performance and production cost.

With a high melting point of nearly 2800℃ and stable chemical inertness, Magnesium Oxide can significantly inhibit the thermal fade of friction coefficient under high braking temperatures. During emergency or continuous braking, the friction interface temperature can reach hundreds of degrees Celsius, and most organic fillers tend to soften and decompose, leading to reduced braking force. Magnesium oxide maintains structural stability at high temperatures, anchors friction interface properties, keeps the friction coefficient stable, and ensures braking safety and consistency.

In terms of wear performance regulation, an appropriate amount of magnesium oxide can optimize the wear rate of friction materials. It not only reduces excessive wear of the brake pad itself, but also avoids scratches and abnormal wear on the brake disc caused by overly hard fillers, protecting the counterpart and extending the service life of the entire braking system. Meanwhile, the excellent thermal conductivity of magnesium oxide can quickly dissipate friction heat, reduce internal thermal stress of brake pads, and lower the risk of thermal cracking and chipping. Its particle gradation can also buffer friction vibration, helping reduce braking noise and jitter, and improving driving comfort.

In addition, magnesium oxide powder has good flowability and adjustable particle size, with excellent compatibility with phenolic resin, reinforcing fibers and other matrices. It adapts to various industrial production processes such as molding and hot pressing, and can replace some high-priced friction additives, making it a cost-effective functional raw material for high-performance brake pad formulations.