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The mechanical properties and surface finish of functional parts are important consideration in rapid prototyping, and the selection of proper parameters is essential to improve manufacturing solutions. The purpose of this paper is to describe how parts manufactured by fused deposition modelling (FDM), with different part orientations and raster angles, were examined experimentally and evaluated to achieve the desired properties of the parts while shortening the manufacturing times due to maintenance costs.

For this purpose, five different raster angles (0°, 30°, 45°, 60° and 90°) for three part orientations (horizontal, vertical and perpendicular) have been manufactured by the FDM method and tested for surface roughness, tensile strength and flexural strength. Also, behaviour of the mechanical properties was clarified with scanning electron microscopy images of fracture surfaces.

The research results suggest that the orientation has a more significant influence than the raster angle on the surface roughness and mechanical behaviour of the resulting fused deposition part. The results indicate that there is close relationship between the surface roughness and the mechanical properties.

The results of this paper are useful in defining the most appropriate raster angle and part orientation in minimum production cost for FDM components on the basis of their expected in-service loading.

The purpose of this paper is to investigate the role of solid lubricants (graphite, coke, ZnS) on brake performance.

In this study, the tribological and surface characteristic of non‐asbestos organic type brake friction materials containing three different solid lubricants (graphite, coke, and ZnS) in different proportions were examined and evaluated experimentally. The coefficient of friction (COF) and wear behavior of the samples were tested on a chase‐type friction tester, and particular emphases were given to the effect of temperature and number of braking cycles on the COF. Each of the lubricants was added to the mixtures in different amounts and seven different brake linings were manufactured, provided that the total amount of solid lubricants and other ingredients were not changed. The worn surfaces of the specimens were analyzed using a scanning electron microscope with energy‐dispersive X‐ray microanalysis.

The experimental results indicate that graphite has a positive effect on the tribological properties of brake linings. However, brake linings containing higher concentrations of ZnS and coke showed an unstable friction coefficient relationship with the temperature and number of braking cycles. The formation of friction layers was detected on the friction surface of these samples, which indicates that an increase in coke and ZnS content increases the discontinuous and unstable friction film areas.

This paper fulfils the effects of solid lubricants (graphite, coke, ZnS) in brake friction materials with detailed tests and analysis.