A sound wear-resistance of internal combustion engine components, such as valvetrain system, remains as a technical challenge for the related industries. Significance of wear resistance of valvetrain system materials becomes increasingly important not only from engine performance standpoint, but also due to increasingly stringent emission control standards placed on the industry.

Although standard ASTM friction and wear testing methods are available, standard testing procedures and evaluation criteria specifically established for valvetrain materials applications have not been established yet. Typically, wear testing of valvetrain materials has been performed by valvetrain manufacturers using in-house developed testing rigs that often cover only very specified engine application conditions.

A review of wear mechanisms in valvetrain materials is made. Demands for developing universally accepted tribo testing methods for valvetrain applications are addressed.