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Low cost and solid lubricant containing plasma spray coated cylinder liners have been investigated for their frictional performance under simulated engine conditions. A bench testing system which has high stroke and large contact width has been used to obtain friction data for plasma spray coated cylinder liners. Results are compared with conventional cast-iron samples. Experimental data has been developed as friction coefficient / crank angle degree diagrams. The effects of speed and temperature have been investigated. Plasma spray coated cylinder liners showed lower friction and higher tendency to develop hydrodynamic lubrication compared to conventional cast-iron bores.

A new friction testing system has been designed and built to simulate the actual engine conditions in friction and wear test of piston-ring and cylinder liner assembly. Experimental data has been developed as Friction Coefficient / Crank Angle Degree diagrams including the effects of running speed (500 and 700 rpm) and ring normal load. Surface roughness profilocorder traces were obtained for tested samples. Mixed lubrication regime observed in the most part of the test range. New cylinder bore materials and lubricants can be screened easily and more reliable simulated engine friction data can be collected using this technique.

The interlaminar shear strength characteristics of unidirectional E-glass fiber/epoxy and vinyl ester composites were investigated. The short-beam flexure test (ASTM D-2344) was utilized for comparing the performance characteristics of the two systems. It was found that E-glass fiber/epoxy composite has higher interlaminar shear strength compared to the vinyl ester composite in dry condition. However, for short-term hygrothermal condition, the retained shear strength values were nearly the same. Optical photomicrography revealed that interlaminar shear damage primarily consisted of fiber-matrix interfacial debonding and matrix cracking. Voids were found to have adverse effect on interlaminar shear strength. The influence of voids was studied in relation to mode II crack or damage propagation.

A dimensionless fatigue life parameter is developed for the correlation of fatigue data of carburized and core material. It is shown that the Smith-Watson-Topper parameter (E σmax ɛa)½ can be generalized to the form to account for the fatigue strength differentials of dissimilar materials such as the core and case-core interface. Fatigue data generated using circumferentially notched specimens (Kt = 1.46 and Kt = 2.22) was successfully correlated to the core material fatigue data using this parameter at low stresses. From these observations, a scheme is proposed to predict low-stress fatigue life of a carburized member experiencing multiaxial stresses based on the core material fatigue response only.