| 摘要 |
FIELD: process engineering. ^ SUBSTANCE: invention relates to powder metallurgy, particularly, to selective laser sintering of 3D articles. It may be used for making complex-shape parts for machine building. Powder layer trial tracks are pre-sintered by sets of combinations of process parameters including radiant power and rate of displacement of minimum-focus laser beam and that of defocused maximum-diameter beam for given conditions of sintering. Digital shooting of sintered trial tracks is carried out to process obtained shots to select optimum sintering conditions by selecting tracks by their maximum width and to sinter every layer of processed part at optimum processing parameters. In every layer sintered are lines of contour 3 by minimum-focus laser beam with maximum gap 4 between first and second points closed by laser beam part equal to Z=0.5ù(H-B), where Z is said gap between first and last points 5, 6; H is width of sintered track; B is track overlap. Sintering of cells areas is carried out by defocused laser beam with overlap of tracks 9 equal to B=(0.05-0.1)H. With laser beam approaching part contour, beam direction is selected to provide for angle between beam travel vector and tangential vector at crossing with part contour makes Ç/4ëñëñÇ/2. ^ EFFECT: higher efficiency and quality. ^ 5 dwg, 1 ex |
