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TiO2-12 wt% Al2O3 coating was deposited on engine cylinder surface by internal plasma spraying to optimize the cylinder-piston tribosystem. The tribological tests were conducted under lubricated conditions on SRV4® reciprocating tribometer. To simulate engine acceleration from cruise to full power, friction parameters of load, frequency and temperature were designated to change over a wide variation, namely 53–157 N, 35–45 Hz and 85–197.5 °C respectively. Accordingly, triboscopic 4D-maps were plotted originally to exhibit the evolution of friction coefficient. Results also showed that cylinders after coating had significant improvement of tribological properties compared with the uncoated specimens, which can be attributed to the great chemical stability to oil, smooth surface roughness during friction, high hardness and H/E of the ceramic coating.

The paper aims at the investigation of the effect of slip ratio on the rolling contact fatigue (RCF) performance of Fe-based alloy coatings. A double-roll test machine is employed to perform the experiment. The result shows that slip ratio has a significant influence on the RCF performance of Fe-based coating. With the increment of the slip ratio, the RCF failure life keeps decreasing but the shape parameter β of Weibull mode decreases first, then increases. The failure mechanism under pure rolling contact condition is the accumulation of micro-pits and the propagation of fatigue cracks within the coating. However, under nonzero slip ratio condition, failure is controlled by the coupling of the cyclic loading action and of the friction force.

this paper investigated on influence of WC–Ni addition on rolling contact fatigue (RCF) behavior of NiCrBSi coating. The results showed that WC–Ni addition significantly influenced on failure mode of NiCrBSi coating especially under low stress, whereas both coatings failed in identical mode under relatively high stress. WC–Ni addition also had a specific influence on RCF lives. RCF Lives of NiCrBSi/WC–Ni coating were longer than NiCrBSi under low stress, but they were almost same under relatively high stress. RCF life distribution of NiCrBSi/WC–Ni coating was more concentrated than NiCrBSi. Besides, there was a potential relationship between Weibull slope and failure mode.

The influence of contact stress on rolling contact fatigue performance of plasma sprayed Al2O3–40 wt% TiO2 composite ceramic coating was investigated using a double-roll test machine under pure rolling contact condition. The shear stresses within the coating were analyzed with the three-dimensional finite element method. Three modes of failures, i.e., surface abrasion, spalling, and delamination, were observed during this investigation. The failure mechanisms of surface abrasion, spalling, and delamination were discussed in detail. The initiation and propagation of fatigue cracks were mainly caused by the shear stress, which were highly influenced by the contact stress.

The competing failure mechanism and life prediction of plasma sprayed Al 2 O 3 -40 wt%. TiO 2 composite ceramic coatings under rolling-sliding contact conditions were investigated on a double-roll test machine. The maximum shear stress distribution in the coatings was analyzed by the finite element method. Weibull function was used to characterize the life distribution of the coatings under different rolling–sliding contact conditions. The failure modes were mainly surface abrasion and adhesive delamination during this investigation. The mechanism of the competing between surface abrasion and adhesive delamination was discussed in detail.

A novel rolling contact fatigue (RCF)/wear competitive life test machine based on double-roll mechanism was designed to investigate the RCF/wear failure mode and predict the competitive life regularity of surface coatings. The test machine was designed for variable slip ratio to simulate the complex service conditions. The failure can be monitored using signals which are acquired from acoustic emission (AE) of the contacting rollers. In the experimental studies, the typical morphologies of RCF damage such as pits, surface abrasion, and delamination were observed. The effectiveness of the AE signals used as a RCF failure monitoring tool was analyzed. The P–N and P–S–N plots were established to predict the life regularity of surface coatings.

The aim of this paper was to address the influence of undercoating on the rolling contact fatigue (RCF) performance of coatings. The Fe-based alloy and Ni/Al alloy were deposited on substrates as surface coating and undercoating by plasma spraying. The failure modes were investigated for two kinds of coatings. RCF performances were compared using Weibull distribution plot. The results showed undercoating played an important role on increasing RCF life of coating for the higher bond strength, and decreasing the scatter of RCF life data. The deposited undercoating could influence the failure mode of coating and prevent the occurrence of catastrophic delamination.