Wear, friction and hardness characteristics of FDM-printed plastic materials

This thesis presents the experimental research of hardness, wear and friction of two different plastic materials which are printed by 3D printer FDM method. Acrylonitrile butadiene styrene and Polylactic Acid are the most popular and frequently used materials. Carbon fiber reinforced acrylonitrile butadiene styrene is the new material that its frictional properties are improved due to carbon. Acrylonitrile, Butadiene and Styrene are three monomer units that acrylonitrile butadiene styrene composed of them. Light weight, thermal resistance and easy formability are some of the versatile properties of ABS. Although most thermoplastic polymers are derived from polymerization of nonrenewable petroleum reserves, polylactic acid is derived from renewable resources. Sugar cane and corn starch are just some of these resources. The usage of structural materials in many engineering demands causes carbon fiber reinforced polymeric materials to enter the industry. Ease of processing, higher strength, the possibility of obtaining complex shapes and recycling make carbon fiber reinforced thermoplastics the scientific interest. Hardness, friction and wear tests are done according to ASTM standards. Test specimen properties, laboratory atmosphere, test specimen conditions and etc. are determined. In the first step the hardness of samples are tested by shore D hardness durometer. The results of this test is compared with primary properties of materials. In the second step pin-on-disc method is used for measuring the friction and wear. Two different loads and speeds are applied to each specimen and this process is repeated five times. Additionally the critical speed value is determined through the tests and considered as the main speed value. The hardness values for ABS, CFABS and PLA materials were improved in compare with molded ones. Generally the better results obtained in the horizontal oriented specimens. Layer thickness had different effect on mechanical properties.