Wear Performance of Circular Shim against Cam in Engine Bench Test.

Unlike the conventional engine, the valve train of a certain type of engine uses a circular shim instead of a tappet to wear against the cam. To verify the reliability of the shim, an engine bench test was used to test its wear performance. The total duration of the bench test was 1000 h, which was divided into three stages.

The Microstructural Evolution of Cu-Sn-P Alloy during Hot Deformation Process.

The microstructure evolution of Cu-Sn-P alloy subjected to hot deformation was researched through electron backscatter diffraction (EBSD) and transmission electron microscope (TEM) in the present study. The results indicated that after hot deformation, grains perpendicular to the force direction were elongated, and mostly became deformed grains, and then exhibited an obvious hardening effect. The Cu-Sn-P alloy could be strain hardened during hot deformation, but, with recrystallization, a softening effect occurred.

Friction reduction mechanism of glycerol monooleate-containing lubricants at elevated temperature - transition from physisorption to chemisorption.

The friction reduction mechanism of glycerol monooleate (GMO) was investigated under boundary lubrication with elevated temperature. Tribological performances were tested using reciprocating test rig by adding 5 wt.% GMO into Poly-alpha Olefin (PAO) base oil.

Effects of Cast-Iron Surface Texturing on the Anti-Scuffing Performance under Starved Lubrication.

Advances in heavy-duty diesel engine designs place higher demands on the friction and wear performance of the piston ring and cylinder liner (PRCL) interface. The potential of using micro-textures machined on the whole stroke of a cast-iron cylinder liner was investigated in this work. A set of running-in and starved lubrication experiments was performed using a custom reciprocating test rig that imparts a combination of combustion-level pressures and the resulting impacts.

Anti-Wear Property of Aluminum⁻Silicon Alloy Treated by Chemical Etching, Mechanical Honing and Laser Finishing.

To enhance the anti-wear property of aluminum-silicon (Al-Si) alloy, three processing technologies-chemical etching, mechanical honing and laser finishing-were compared in terms of their effects on anti-wear performance. The treated Al-Si alloy cylinder liner samples were worn against a piston ring by a reciprocating sliding tribotester; the anti-wear performance was represented by the friction coefficient and wear loss; and the wear mechanism was determined by establishing stress contact models. The results showed that the best time for both the chemical etching and mechanical honing treatments was 2 min, and the optimal laser power was 1000 W for the laser finishing treatment.