Superconducting thin films are widely used in superconducting quantum interferometers,microwave devices,etc.The electrical performance of a superconducting thin film is often affected by structural deformation or stre...Superconducting thin films are widely used in superconducting quantum interferometers,microwave devices,etc.The electrical performance of a superconducting thin film is often affected by structural deformation or stress.Based on four-point bending of a Cu-Be beam,we constructed a device that could apply uniaxial,uniform.compressive strain to a superconducting thin film at both room temperature and the temperature of liquid nitrogen.The thin film was placed into a slot carved in the Cu-Be beam.We optimized the size of this slot via numerical simulation.Our results indicated that the slot width was optimal when it was same as the width of the Cu-Be beam.Notably,the sample bended hardly after machining two slits along width direction on both sides of the slot.A YBa2Cu3O7-δSrTiO3(YBCO-STO)film was used as an example.It was loadedby the aforementioned device to determine its electrical characteristics as functions of the uniaxial-uniform-compressive strain.The optimized design allowed the sample to be compressed to a larger strain without breaking it.展开更多
The residual stress is formed in YBa_(2)Cu_(3)O_(7-δ) (YBCO) bulk superconductors,which undergoes a complex fabrication process and experienced a huge temperature change about 1000℃.The residual stress may result in...The residual stress is formed in YBa_(2)Cu_(3)O_(7-δ) (YBCO) bulk superconductors,which undergoes a complex fabrication process and experienced a huge temperature change about 1000℃.The residual stress may result in micro-cracks in YBCO bulks and cause degradation of its superconducting and mechanical properties.It will be greatly helpful to reform the structural designs if the distribution of residual stress in YBCO bulk can be investigated.The traditional method of measuring residual stress does not apply to oxide ceramics as they are brittle materials.In this paper,a YBCO bulk was sliced into pieces of several millimeters in height,which could thus be treated as a plane-stress problem.The residual stress and principal stress angle for YBCO bulk have been obtained by an artificial hole-drilling method with very low speed.展开更多
基金the National Natural Science Foundation of China(Grants 11622217,11872196,and11902130)the Fundamental ResearchFunds for the Central Universities(Grant lzujbky-2018-9).
文摘Superconducting thin films are widely used in superconducting quantum interferometers,microwave devices,etc.The electrical performance of a superconducting thin film is often affected by structural deformation or stress.Based on four-point bending of a Cu-Be beam,we constructed a device that could apply uniaxial,uniform.compressive strain to a superconducting thin film at both room temperature and the temperature of liquid nitrogen.The thin film was placed into a slot carved in the Cu-Be beam.We optimized the size of this slot via numerical simulation.Our results indicated that the slot width was optimal when it was same as the width of the Cu-Be beam.Notably,the sample bended hardly after machining two slits along width direction on both sides of the slot.A YBa2Cu3O7-δSrTiO3(YBCO-STO)film was used as an example.It was loadedby the aforementioned device to determine its electrical characteristics as functions of the uniaxial-uniform-compressive strain.The optimized design allowed the sample to be compressed to a larger strain without breaking it.
基金supported by the fund of Natural Science Foundation of China(Nos.11872196,11902130).
文摘The residual stress is formed in YBa_(2)Cu_(3)O_(7-δ) (YBCO) bulk superconductors,which undergoes a complex fabrication process and experienced a huge temperature change about 1000℃.The residual stress may result in micro-cracks in YBCO bulks and cause degradation of its superconducting and mechanical properties.It will be greatly helpful to reform the structural designs if the distribution of residual stress in YBCO bulk can be investigated.The traditional method of measuring residual stress does not apply to oxide ceramics as they are brittle materials.In this paper,a YBCO bulk was sliced into pieces of several millimeters in height,which could thus be treated as a plane-stress problem.The residual stress and principal stress angle for YBCO bulk have been obtained by an artificial hole-drilling method with very low speed.
