硅溶胶浸渗对SLS覆膜砂表面质量的影响

Effects of Silica Sol Infiltration on Surface Quality of Selected Laser Sintering (SLS) Coated Sand

通过对选区激光烧结(SLS)覆膜砂型浸渗硅溶胶后处理强化,研究浸渗硅溶胶对精密铸造用SLS砂型表面粗糙度的影响。结果表明,随着硅溶胶浸渗温度的升高及时间的延长,SLS覆膜砂铸型表面粗糙度均呈先减小后增大的趋势,当硅溶胶浸渗温度为30℃、浸渗时间为15h时,覆膜砂铸型表面粗糙度最小,Ra为11.48μm;随着覆膜砂后固化温度及时间的提高,SLS覆膜砂铸型表面粗糙度均呈先减小后增大的趋势,当覆膜砂后固化温度为30℃、固化时间为15h时,覆膜砂铸型表面粗糙度(Ra)最小为13.96μm。

The effects of infiltrating silica sol process on mould surface roughness of SLS coated sand were investigated by infiltrating silica sol and post-processing into green part of SLS coated sand.The results reveal that,with the increase of the temperature and time of the silica sol infiltration,the surface roughness of the SLS coated sand mold is reduced firstly and then increased.With the silica sol infiltration at30 ℃for 15 h,the surface roughness of coated sand casting reaches the maximum value（Ra）of 11.48μm.With the increase of curing temperature and time of coated sand,surface roughness of SLS coated sand mould are decreased firstly and then increased.With the coated sand after curing temperature at 30℃for 15 h,the minimum surface roughness of coated sand casting reaches（Ra）13.96μm.