Papers by Author: Pei Jing Shi

Abstract: Based on total life cycle assessment (TLCA) and a research project on auto engine remanufacturing, this article look forward to make certain what is "Remanufacturing Rate" of engine remanufacturing and how to express it on the occasions of OEMs, independent remanufacturers and subcontracted remanufacturers in China. The concepts of ‘Remanufacturing rate’ of engine are put forward at first, and then the estimate methods are studied based on remanufacturing environment of China.

Abstract: As new engineering coatings get ever thinner and more technologically advanced, there is an increasing demand for accurate assessment of the mechanical properties of thin films. The rapidly expanding field of depth-sensing evaluation and techniques related provides a quantitative method for mapping the micro/nano mechanical properties. A new type of nano test system was introduced, the technology principle and the data analysis method were described. It was used to test the performance of brush-plated nanocomposite coatings, supersonic plasma-sprayed coatings and self-repairing microcapsule for corrosion-proof coatings, including the distribution of mechanical properties across the surface and the section and nanoindentation creep. The results show that nanoindentation techniques play an incomparable role in charactering the performance of surface coatings.

Abstract: Tribological properties of silicate particles as 50CC additive were evaluated on an end-face friction and wear tester. The morphologies, element distributions and micro-mechanical properties of the worn surface were investigated by means of scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and nanoindentation tester, respectively. Results indicate that friction reduction and wear resistance properties of 50CC are improved effectively by adding silicate particles, whose main composition is Mg3[Si2O5](OH)4. The friction coefficient and surface temperature are reduced 60.6% and 35.6%. The nano-hardness of the self-repairing film is increased 30.03% compared with that of the ordinary film. It can be inferred that a high nano-hardness protective film composed of Mg, Al and O is formed on the worn surface, which has a good effect on the tribological performances.

Abstract: A special kind of surface modified copper nanoparticles was selected as the auto-reconditioning materials to in situ generate a copperized protective film on iron-base metal surfaces under designed tribological conditions. The morphologies and element distributions of the formed film were observed and determined by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The micro mechanical properties and tribological behaviors were investigated by nano test system and ball-on-disc tribotester. The results show that the morphology of the protective film is smooth, the nano-hardness decreases by 46% and the friction coefficient of the copperized protective film is about 0.10. The forming mechanism of the auto-reconditioning film can be described that the copper nanoparticles deposit on the worn surfaces and form iron-copper alloy film with lower hardness and shear strength, which has better friction-reducing, antiwear and surface-optimizing behaviors.