Development of a Powder Metallurgy Sensor Ring for Use In a Antilock Brake System

The sensor ring for Antilock Brake Systems was developed by the Powder metallurgy(P/M) process. The P/M process provides the following merits;better dimensional tolerance, flexibility of tooth design, versatility of the materials, and better economics.

Residual porosity introduced by the P/M process decreases the output voltage of the sensor. A representative porosity of 10% was confirmed to be allowable.

By developing a new surface treatment suited to P/M parts which contain the residual porosity, we succeeded in developing the P/M sensor ring which can endure a 500 Hr. salt spray test.