The　IC10　single　crystal　superalloys　are　welded　by　the　laser　welding　process,　and　the　effects　of　welding　speed　on　joint　weld　forming,　cross-section　morphology　and　microstructure　are　analyzed.　The　results　show　that　the　surface　and　back　widths　of　welds　increase　with　the　decrease　of　welding　speed.　The　cross-sections　of　welds　under　different　welding　speeds　all　show　a　typical　goblet　shape.　The　welds　mainly　consist　of　fine　grains,　cellular　crystals　and　columnar　crystals.　The　welding　cracks　extending　along　the　grain　boundaries　always　occur　in　welds　under　different　welding　speeds.　The　growing　direction　of　the　grains　in　joints　tends　to　be　the　same,　which　increases　the　cracking　susceptibility　of　joints.　©　2018,　Chinese　Lasers　Press.　All　right　reserved.