Thedependencesofradiationinduceddefectsonirradiationtemperatureupto700℃at15dpaandonirradiationdoseupto85dpaatroomtemperaturehavebeeninves-tigatedbytheheavyionirradiationandthepositronannihilationlifetimespectroscopyfortheCLAM.Avoidsizepeakisobservedat~500℃wherethevacancyclustercontains9vacanciesandhasanaveragediameterof0.59nm.Thesizeofthevacancyclustersincreaseswiththeincreaseofirradiationdoseatroomtemperature,andthevacancyclusterat85dpaconsistsof9vacanciesandreachesasizeof0.60nmindiameter.TheabsolutevaluesofthevoidsizeatthepeakandtheincreaseofvoidsizewithdoseintheCLAMsteelarenegligiblecomparedtothoseofthenormalstainlesssteels,indicatingthattheCLAMsteelhasgoodradiationresistantproperty.