Effect of weight percentage of alumina on mechanical properties of nanocomposite produced by additive manufacturing method of digital light processing

In this study, the production of nanocomposite samples was investigated using digital light processing (DLP). First, the effect of the thickness of the printing layer in three values of 50, 75, and 100 micrometers on the tensile properties of neat and composite resin samples as well as the printing time was investigated. Next, by adding different amounts of aluminum oxide nanopowder with a particle size of 50 nm to the resin, the effect of different percentages of nanopowder on the mechanical properties of the samples, including tensile strength and wear resistance, was investigated. The results showed that samples with less layer thickness have better strength than samples with more layer thickness. By reducing the thickness of the layer from 100 to 75 and 50 micrometers, the tensile strength in neat samples increases by 4 and 8.55%, respectively. Also, with the increase of alumina up to 2% by weight, the tensile strength first decreases, and then with the continued increase in the number of reinforcing particles, the tensile strength improves, so that finally, with 8% by weight of alumina, the tensile strength shows an increase of nearly 16% compared to the neat resin sample. . In addition, with the increase in the weight percentage of alumina in the nanocomposite, the wear resistance first weakens and then improves, and finally (similar to the tensile strength) at 8 weight percent of reinforcing particles, the specific wear rate decreases by nearly 67% compared to the neat resin sample.