Effect of heat treatment process on microstructure and mechanical properties of 0Cr17Ni4Cu4Nb stainless steel

Effects of solution temperature,aging temperature and the cooling methods on microstructure and mechanical properties of 0Cr17Ni4Cu4Nb stainless steel were studied by means of transmission electron microscope,scanning electron microscope,X-ray diffraction meter,optical microscope and mechanical property tester.And the heat treatment process for large forgings of the stainless steel was deduced.The results show that the 0Cr17Ni4Cu4Nb steel can obtain preferable comprehensive mechanical properties by 1040 ℃ solution treatment with oil cooling.Effect of aging cooling rate on mechanical properties of the alloy is negligible,it is appropriate to 0Cr17Ni4Cu4Nb steel to be aged at 480 ℃ with air cooling,as a result the strength is qualified and the toughness is relatively higher.It is concluded that the optimal heat treatment process of 0Cr17Ni4Cu4Nb steel is solution treatment at 1040 ℃with oil cooling and aging at 480 ℃ with air cooling.