An investigation was conducted to examine the low cycle symmetric push-pull fatigue behaviour of the Cr-Mn-N dual-phase stainless steel.Two groups of specimens,A and B, were used,they were solution treated at 1050 and...An investigation was conducted to examine the low cycle symmetric push-pull fatigue behaviour of the Cr-Mn-N dual-phase stainless steel.Two groups of specimens,A and B, were used,they were solution treated at 1050 and 1250℃,respectively.The.fatigue life of group A is almost twice as long as that of group B under the same total strain amplitude.The energy loss during the fatigue tests and the mophology of the fracture surfaces have been stu- died and discussed.展开更多
High temperature low cycle fatigue tests on GH4742 superalloy were studied under the total strain-con- trolled conditions at 650 ℃. Combined with fatigue test data, fatigue properties of the alloy were analyzed. Frac...High temperature low cycle fatigue tests on GH4742 superalloy were studied under the total strain-con- trolled conditions at 650 ℃. Combined with fatigue test data, fatigue properties of the alloy were analyzed. Fracture morphology and dislocation structure were observed by scanning electron microscopy and transmission electron mi- croscopy. The results showed that fatigue life and fatigue resistance of GH4742 alloy decreased significantly with in- creasing total strain amplitude. The cyclic hardening, cyclic softening and cyclic stability phenomena of the alloy oc- curred during the low cycle fatigue process. The increasing total strain amplitude is conducive to the formation of γ1 phase. Fatigue crack propagation is controlled jointly by ductile and brittle fracture. Inhomogeneous deformation and deformation restricted in slip bands are the main reasons for the reduction of fatigue life of GH4742 alloy.展开更多
文摘An investigation was conducted to examine the low cycle symmetric push-pull fatigue behaviour of the Cr-Mn-N dual-phase stainless steel.Two groups of specimens,A and B, were used,they were solution treated at 1050 and 1250℃,respectively.The.fatigue life of group A is almost twice as long as that of group B under the same total strain amplitude.The energy loss during the fatigue tests and the mophology of the fracture surfaces have been stu- died and discussed.
基金Sponsored by Major National Science and Technology Project of High-end CNC Machine Tools and Basic Manufacturing Equipments of China(2012ZX04010081)
文摘High temperature low cycle fatigue tests on GH4742 superalloy were studied under the total strain-con- trolled conditions at 650 ℃. Combined with fatigue test data, fatigue properties of the alloy were analyzed. Fracture morphology and dislocation structure were observed by scanning electron microscopy and transmission electron mi- croscopy. The results showed that fatigue life and fatigue resistance of GH4742 alloy decreased significantly with in- creasing total strain amplitude. The cyclic hardening, cyclic softening and cyclic stability phenomena of the alloy oc- curred during the low cycle fatigue process. The increasing total strain amplitude is conducive to the formation of γ1 phase. Fatigue crack propagation is controlled jointly by ductile and brittle fracture. Inhomogeneous deformation and deformation restricted in slip bands are the main reasons for the reduction of fatigue life of GH4742 alloy.
