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This paper presents the results of simulation analyses carried out to investigate the effect of adding controlled vibration of varying amplitudes and frequencies onto simulated workpiece profiles on surface roughness. The surface profiles were generated using the nose edge image of a real cutting tool insert at various stages of wear. The invariant moment sub-pixel edge detection method was used to extract the precise tool nose profile. The extracted nose profile was duplicated 20 times to generate the simulated workpiece profile. Vibration signals in the form of sine waves of amplitudes 0 to 50 % of the peak-to-valley height of the original workpiece profile and various frequencies were added to the simulated profile. Noise signals emanating from real machining were also added to the original profile to investigate their effect on roughness. The simulation study has shown that average roughness may increase continuously or fluctuate randomly depending on the magnitude of vibration added to the vibration-free workpiece profile. In the absence of vibration, the surface roughness of the workpiece decreases due to flattening effect of the tool nose during early stages of tool wear.

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A short review was conducted with regards to functions of dimple structures to increase the heat transfer efficiency. Dimples are among the important structure in surface texturing used to improve the parts performance such heat transfer efficiency. A review of the results of previous research found that dimple surfaced can enhance the heat transfer rate by up to 150% compared to smooth surfaces, and in certain cases the heat transfer rate is about 2.5 times higher than that of smooth surfaces. Therefore, it is believed that the dimple structure can help to enhance the product performance in various applications especially involved high temperature service conditions.