1990-02-01

Ceramic Tappets Cast in Aluminum Alloy for Diesel Engines 900403

The authors developed, for use in diesel engines, ceramic tappets cast in aluminum alloy that drastically improved wear resistance and valve train dynamics.
The ceramic tappets consist of two parts: a ceramic head, which contacts the cam and push rod, and a tappet body made of aluminum alloy. Concerning the ceramic, silicon nitride was the best material of the three ceramics evaluated in the tests and the sliding surface, in contact with the cam and push rod, was left unground. As for the aluminum alloy, hyper-eutectic aluminum-silicon alloy with a controlled pro-eutectic silicon size was selected.
A reliability analysis using the finite-element method (FEM) was also made on the structure of the ceramic tappet for enhanced durability and reliability.
The combination of this tappet and a cam made of hardened ductile cast iron, hardened steel, or chilled cast iron, respectively exhibits excellent wear resistance.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 43% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.
X