Abstract:
The objectives of this research were to study mechanical properties of ultra-high
molecular weight polyethylene mixed with lightweight metal reinforcements and to study
tribological performance of ultra-high molecular weight polyethylene mixed with
lightweight metal reinforcements. The two materials used in the research included ultrahigh molecular weight polyethylene (UHMWPE) as the main material and aluminum
powder as an additive. The variables used in the hot extrusion process to obtain the
material for the experiment consisted of extrusion force, temperature, time, and mixing
ratio between ultra-high molecular weight polyethylene and aluminum powder at 2.5, 0.5,
7.5, and 10 percent by weight. The testing of mechanical properties and tribological
performance included Izod polymer impact testing according to ASTM D2 5 6 standard,
hardness testing according to ASTM D2 2 4 0 standard, tensile testing according to ASTM
D638 type I standard, wear testing according to ASTM G77 standard, the hot extruded test
piece under the pressure of 5 MPa at the temperature of 140°C for 3 hours. The testing
results of mechanical properties on the hot-extruded test piece with UHMWPE and
aluminum powder mixture demonstrated that at aluminum powder mixing ratio at 10
percent by weight showed the highest average increase, consisting of Yield Stress at 27.55 MPa, Ultimate Tensile Strength at 32.76 MPa, Breaking Strength at 22.83 MPa, Elongation at Break at 287.80 percent, Modulus of Elasticity at 740.60 MPa and Shore D hardness at 62. However, at this mixing ratio, it was found that the lowest impact strength was at 35.80 kJ/m2 . The results of tribology performance of the hot-extruded test piece with UHMWPE and aluminum powder mixture showed that the aluminum powder mixing ratio at 1 0 percent by weight yielded the highest increase. The average values of the coefficient of friction and the density were 0.15 and 1.865654 g/cm3, respectively. At this mixing ratio, it was found that the wear rate decreased on the average of 6.89E-10 mm3/N m.