Although the EU Stage 7 standard has not yet been finalized, Impact Innovations has developed a solution for the particulate matter (PM10) emission limits—Impact Hybrid Brake Disc Coating® (Impact Hybrid BDC®). This coating not only complies with the 7 mg/km limit but is also expected to meet the stricter 3 mg/km limit. At the same time, Impact Hybrid BDC® has demonstrated excellent performance in the most demanding crack and corrosion tests, showing no delamination. BMW Group relies on Impact Hybrid BDC® in its BMW M series models to ensure compliance with the EU Stage 7 standard.

Through Impact Hybrid BDC®, Impact Innovations combines two technological domains into a single brake disc coating: a strong metallic bond achieved by a laser-cladded intermediate layer and a cold-sprayed top layer that provides crack resistance and corrosion protection.

The laser-cladded intermediate layer achieves the highest metal bonding strength with the cast gray iron brake disc without requiring any surface treatment. This thin intermediate layer has a limited thermal impact on the brake disc, thereby preventing thermal distortion. At the same time, the surface of the intermediate layer offers an ideal topography for the application of the cold-sprayed top layer, enabling equally high adhesion strength without any further surface treatment.

During the cold-sprayed top layer application, the higher kinetic energy reduces the tensile stresses applied to the intermediate layer. Additionally, the compressive strength of the cold-sprayed top layer creates a high-performance coating that delivers maximum crack resistance even under the most demanding test conditions.

The Impact Hybrid Brake Disc Coating® (patent pending) is able to prevent severe cracking under the highest braking stresses and corrosive environments. As a result, corrosion between the gray cast iron disc and the coating—and any delamination caused by it—is effectively eliminated.

The intermediate layer can be produced using low-cost standard powders. The titanium-based matrix material of the top layer ensures the highest corrosion and crack resistance. Even after 720 hours of salt spray testing, no corrosion was detected.

A wide variety of hard alloy materials are suitable for the top layer, allowing significant cost reductions by using low-cost carbides such as silicon carbide.

The surface temperature during coating application and the resulting thermal stress on the brake disc are minimized, so no significant disc deformation is measurable (no bell mouthing, no warping).

This leads to a reduction in grinding allowance, thereby minimizing the coating thickness (and related coating costs) as well as grinding costs.

Combined with the latest custom brake pad developments from leading brake pad manufacturers, particulate emissions can be significantly reduced, making it possible to meet the lowest emission limits below 3 mg/km. At the same time, these specially designed brake pads provide very stable performance and the required friction values.

Advantages

· Achieves the highest-performance coating solution by combining two state-of-the-art brake disc coating technologies

· Provides the highest metal bonding strength with gray cast iron

· Prevents thermal deformation of the brake disc

· Avoids severe cracking through the compressive stress of the cold-sprayed top layer

· Offers the longest corrosion and wear resistance

· Ensures lowest coating and grinding costs due to robust cold-spray technology

· Enables maximum particulate emission reduction through optimized brake pad materials

Meanwhile, Impact Hybrid Brake Disc Coating® has been technically approved by BMW Group and other OEMs. This means that Impact Hybrid BDC® is currently undergoing final evaluation for series production within BMW Group.