The　410　stainless　steel　(SS410)　large-size　block　part　without　defects　was　successfully　prepared　by　cold　metal　transfer　(CMT)　wire-arc　additive　manufacturing　(WAAM).　Results　showed　that　5-ferrite　in　SS410　could　be　eliminated　during　deposition　without　any　extra　post-treatment.　The　content　of　martensite　in　the　central　zone　and　overlap　zone　both　exceeded　96%,　and　the　rest　was　punctate　austenite.　The　average　strength/elongation　of　the　as-deposited　(AD)　block　part　was　1323　MPa/4.1%.　By　comparing　the　tensile　properties　of　AD　samples　with　low-temperature　annealing　(LA),　full　annealing　(FA),　and　high　temperature　tempering　(HT)　post-heat-treated　samples,　the　HT　could　achieve　the　best　balance　of　strength　and　ductility　with　an　elongation　about　12.7%.　This　work　proved　that　the　high-performance　parts　could　be　prepared　through　WAAM　by　using　appropriate　processing　parameters.　(C)　2021　Published　by　Elsevier　B.V.