日本合金结构钢SMn420 SMn433 SMn438 SMn443 SMnC420 SMnC443 SCr415 SCr420 SCr430 SCr435 SCr440 SCr445 SNC236 SNC415 SNC631 SNC815 SNC836 SNCM220 SNCM240 SNCM415 SNCM420 SNCM431 SNCM439 SNCM447 SNCM616 SNCM625 SNCM630 SNCM815 SCM415 SCM418 SCM420 SCM421 SCM430 SCM432 SCM435 SCM440 SCM882 SACM645 SMn420H SMn433H SMn438H SMn443H SMnC420H SMnC443H SCr415H SCr420H SCr430H SCr435H SCr440H SNC415H SNC631H SNC815H SNCM220H SNCM420H SCM415H SCM418H SCM420H SCM435H SCM440H SCM445H SCM822H