A　micro　scale　3D　finite　element　model　(FEM)　with　consideration　of　powder　arrangements　was　developed　by　selective　laser　sintering　(SLS),　where　a　multi-layer　powder　stacking　model　with　cubic　powders　inter-laced　each　other　was　established　to　describe　the　porous　powder　bed.　All　the　powders　directly　exposed　to　laser　irradiations　were　loaded　with　the　Gaussian　function　of　heat　flux,　and　the　non-linear　thermal　conductivity　and　specific　heat　owing　to　temperature　change　and　phase　transformation　were　considered.　Comparison　between　the　modeling　and　experiment　indicated　that　both　the　simulated　length　of　the　sintered　piece　and　shrinkage　depth　of　the　powder　bed　agreed　well　with　the　experiment　data.　The　temperature　field　of　laser　sintering　was　intermittent　in　the　micro　scale　due　to　the　discretely　distributed　particles　with　maximum　temperature　produced　in　the　top　layer　of　the　powder　bed,　and　two　primary　ways　of　bonding　were　found　in　the　powder　bed　during　laser　sintering.　(C)　2012　Elsevier　B.V.　All　rights　reserved.