METHOD AND APPARATUS FOR LASER SINTERING Russian patent published in 1999 - IPC

FIELD: metallurgy, namely technique of laser sintering in different branches of machine engineering. SUBSTANCE: multibeam laser apparatus forms sintering beam 64 having focus on powder layer 68 and at least one unfocused laser beam 116 incident on zone near focus of beam 64. Sintering beam 64 increases temperature of powder 84 up to sintering temperature. Unfocused beam 116 raises temperature of material surrounding sintering beam 64 until temperature lower than sintering temperature thereby decreasing temperature gradient between sintering zone and surrounding material. Heat irradiation of one or both beams may be measured and used for controlling power of one or both beams in order to sustain necessary temperature level. In variant several unfocused beams may be used for providing multistep temperature gradient or for independent temperature control of each zone near sintering spot. EFFECT: lowered warping of products. 35 cl, 15 dwg