This paper presents experimental investigations on influence of important process parameters: laser power, scan speed,
layer thickness, hatching space along with their interactions on dimensional accuracy of Selective Laser Sintering (SLS)
processed pro-coated sand mold. It is observed that dimensional error is dominant along length and width direction of
built mold. Optimum parameters setting to minimize percentage change in length and width of standard test specimen
have been found out using Taguchi's parameter design. Optimum process conditions are obtained by analysis of variance
(ANOVA) is used to understand the significance of process variables affecting dimension accuracy. Scan speed and
hatching space are found to be most significant process variables influencing the dimension accuracy in length and
width. And laser power and layer thickness are less influence on the dimension accuracy. The optimum processing
parameters are attained in this paper: laser power 11 W; scan speed 1200 mm/s; layer thickness 0.5 mm and hatching
space 0.25 mm. It has been shown that, on average, the dimensional accuracy under this processing parameters
combination could be improved by approximately up to 25% compared to other processing parameters combinations.
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