Fracture　toughness　can　be　measured　by　microscratch　test　from　objective　force　and　depth　measurement,　which　is　much　convenient　than　indentation　approach　and　conventional　means,　since　initial　notch　or　pre-crack　is　not　required.　Micro-scratch　test　was　conducted　on　copper　under　a　spherical　probe　of　radius　105　μm　and　constant　applied　normal　load　with　the　aim　of　characterizing　fracture　toughness　of　copper　by　sliding　technique　with　a　sphere.　Scratch　variables　such　as　normal　load,　lateral　load,　friction　coefficient,　and　penetration　depth　were　analyzed,　and　different　methodologies　for　calculating　fracture　toughness　were　compared.　Linear　elastic　fracture　mechanics　was　found　to　be　inapplicable　to　scratch　of　elastic-plastic　material　with　sufficient　plasticity　under　a　spherical　probe,　while　energetic　size　effect　law　can　be　successfully　applied　to　characterize　fracture　toughness　by　microscratch　test　with　a　sphere　abrading　metallic　material.　©　2019　Elsevier　B.V.