Design and operation of a high temperature wear test apparatus for automotive valve materials

• A new apparatus to wear test valves at high temperatures was developed.
• The apparatus can reduce the time to develop new materials for valves.
• Illustrative data for SAE 4340 steel for VSI and SAE EV12 21-2N are presented.
• The use of this wear test in conjuction with dynamometers is discussed.

A current trend in the automotive industry is to reduce the engine size while increasing power. The valve and valve seat perform the functions of ensuring the entry of air and combustible material, the output of combustion gases and sealing during the compression and combustion processes. As a result, the pair valve and seat are the most critical components in high-efficiency engines. To ensure the robustness of their operation while providing clean combustion and low emissions, the use of the correct materials is required. The high temperatures of the exhaust gases, the velocities of the valves and the high operating pressures are several of the parameters that cause wear on the valve seats and valves. The materials used to create the valve must be characterized by good workability, high wear resistance, good mechanical strength and good fatigue and corrosion resistance at high temperatures. However, the tests applied to develop new materials are limited to lower temperatures than those expected in the next generation of combustion engines. In this study, the development of a new valve seat and valve test machine for high temperatures is presented. A comparison of the currently available designs of apparatuses for this purpose is also presented with the new proposed design. The results of testing the valve seats and valves using this new design are presented and evaluated along with the results of the standard test machines.