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The Selective Laser Melting (SLM) process based additive manufacturing has wide applications in medical, aerospace, defense, and automotive industries. To qualify the components for certain tribological applications, the characterization of surface texture is very important. But the applicability of traditional methods and parameters to characterize the surface texture were under evaluation. As the nature manufacturing the components were very different and complex, the unconventional surface characterization methods also under evaluation to reveal much more meaningful information. This study demonstrates the surface characterization of Ti-6Al-4V SLM components using fractal analysis of the surface images. The computed fractal dimension using the Fourier transform method showed a strong correlation of more than 0.8 with the measured 3D surface roughness parameters. The change in anisotropic nature of the surface images with the process parameter variation is studied and found that the surface textures showed a weaker anisotropic nature at lower laser power ranges, high scanning speed, and high hatch distance values. The lacunarity analysis is carried out using the gliding box algorithm to study the homogeneity nature of the surface texture and found that the surface texture is more homogeneous at higher surface roughness conditions. The study results can be utilized for the development of a quick, low-cost surface monitoring system in real-time for additive manufacturing industries.

Roundness is one of the common attribute in the manufacturing industry. Roundness is the most prominent of the extant fundamental forms, as the majority of the fabricated components are round or cylindrical. The examination of roundness error associated with such features is critical since inadequate evaluation might result in the rejection of excellent parts. The performance of any equipment depends on the mating parts. Out-of-roundness components cause the inefficiency of such equipment's system performance. As a result, roundness error assessment is critical for macro-sized specimens as well as micro- and nano-sized components. The present article proposes a novel approach to Minimum Zone Circle (MZC) to evaluate the roundness error. An iterative field search methodology is used in the suggested approach. The recommended method is quite effective in assessing the roundness error when compared to existing techniques. It also worked well on data that was both evenly and unevenly spaced. The results suggest that altering the search field area for higher computing efficiency is straightforward, resilient and versatile.

A specified geometry of diamond indenter with different rake angles such as 0°, −2° and −4° were used in single scratch experiments to study the mode of material removal on both the sintered and pre-sintered yttria-stabilized tetragonal zirconia (Y-TZP). To evaluate these features during the scratch experiment, the generated forces and the acoustic emission signals were correlated with the surface morphology of scratches. The results indicated that the forces generated by the higher negative rake angle (−4°) increase with reduced chipping in comparison with other rake angles.The material removal above 5 μm scratch depth for sintered zirconia resulted in a brittle fracture, whereas a quasi-plastic behavior was observed with microcracks leading to a clumsy chip in pre-sintered zirconia. This was analyzed from the morphology of the chips and the scratches produced. The formation of chipping was reduced with the increase in negative rake angle, indicated by the changes in the features of the acoustic emission signal. The major frequency peaks were formed at a lower level below 250 kHz denoted the predominant brittle fracture. The acoustic emission burst occurred in the sintered component, which indicated the cracking and chipping formation was more compared to the pre-sintered block.