In　this　study,　WC-12Co　cemented　carbides　were　fabricated　by　selective　laser　melting　(SLM)　and　subsequently　subjected　to　sintering.　Effects　of　the　scanning　speed　on　the　microstructure,　mechanical　properties　and　friction　and　wear　performance　of　the　prepared　WC-12Co　cemented　carbides　were　investigated.　Based　on　the　XRD　spectra,　eta　phase　appeared　after　the　SLM　process,　confirming　a　loss　of　carbon　during　the　preparation　of　WC-12Co.　The　WC　average　grain　size　increased　with　improving　the　scanning　speed,　which　fluctuated　in　the　range　of　1.5　mu　m-2.5　mm.　The　relatively　small　WC　average　grain　size　was　associated　with　the　lamellar　structure　(alternating　layers　of　coarse　and　fine　WC　grains)　caused　by　the　uneven　temperature　distribution　of　SLM.　Co　evaporation　was　quantitatively　revealed　by　EBSD　phase　maps.　Relationships　between　hardness,　transverse　rupture　strength　(TRS)　and　scanning　speeds　were　analyzed.　The　comprehensive　performance　of　the　samples　reached　the　best　at　the　scanning　speed　of　400　mm/s,　which　the　hardness,　TRS　was　81　HRA,　and　650　MPa,　respectively.　Furthermore,　after　process　optimization,　the　friction　and　wear　properties　of　the　material　were　tested,　the　friction　coefficient　was　about　0.2　at　room　temperature,　while　0.5-0.7　at　200　degrees　C-600　degrees　C.　(C)　2022　The　Author(s).　Published　by　Elsevier　B.V.