In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition...In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition(LDED).The effects of ultrasonic vibration(UV)and tempering treatment on microstructure evolution,microhardness distribution and mechanical properties of deposition layer were studied in detail.The microstructure of UV assisted LDED sample after tempering is mainly composed of tempered sorbite(TS).Due to the improvement of microstructure inhomogeneity and grains refinement,UV assisted LDED sample with tempering treatment obtains excellent mechanical properties.The ultimate tensile strength(UTS),yield strength(YS)and elongation after breaking(EL)reach 765 MPa,657 MPa and 19.5%,the increase ratios of UTS and YS are 14.5%and 33.8%while maintaining plasticity compared to original LDED sample,respectively.It is obvious that ultrasonic vibration combined with tempering is a potential and effective method to obtain uniform microstructure and excellent mechanical properties in metal laser directed energy deposition field.展开更多
This paper introduces the research and development of high strength A517Q developed by Baosteel for platform rack,with micro-alloying adding suitable quenching and tempering process,trial thickness of 127-178 mm high-...This paper introduces the research and development of high strength A517Q developed by Baosteel for platform rack,with micro-alloying adding suitable quenching and tempering process,trial thickness of 127-178 mm high-strength A517Q.The trial plate crossing thickness has a uniform mechanical properties,yield strength greater than 700 MPa,tensile strength than 790 MPa,the Charpy impact than 90 J at-40℃,aging impact than 69 J,has high strength and excellent low temperature impact toughness,While the plate has excellent resistance to crack tearing ability of low-temperature,NDT is less than-45℃.The Developing heavy plates had been used for manufacturing racks of 200-foot jack-up offshore platform,the performance meeting the requirements of the ABS,CCS classification societies.展开更多
基金Project(2021YFC2801904) supported by the National Key R&D Program of ChinaProject(KY10100230067) supported by the Basic Product Innovation Research Project,China+3 种基金Projects(52271130,52305344) supported by the National Natural Science Foundation of ChinaProject(ZR2022QE073) supported by the Natural Science Foundation of Shandong Province,ChinaProject(AMGM2021F01) supported by the Science Fund of Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai,ChinaProject(KY90200210015) supported by Leading Scientific Research Project of CNNC,China。
文摘In this work,ultrasonic energy field assistance combined with tempering treatment is proposed to improve the microstructure and mechanical properties of A517Q alloy steel fabricated by laser directed energy deposition(LDED).The effects of ultrasonic vibration(UV)and tempering treatment on microstructure evolution,microhardness distribution and mechanical properties of deposition layer were studied in detail.The microstructure of UV assisted LDED sample after tempering is mainly composed of tempered sorbite(TS).Due to the improvement of microstructure inhomogeneity and grains refinement,UV assisted LDED sample with tempering treatment obtains excellent mechanical properties.The ultimate tensile strength(UTS),yield strength(YS)and elongation after breaking(EL)reach 765 MPa,657 MPa and 19.5%,the increase ratios of UTS and YS are 14.5%and 33.8%while maintaining plasticity compared to original LDED sample,respectively.It is obvious that ultrasonic vibration combined with tempering is a potential and effective method to obtain uniform microstructure and excellent mechanical properties in metal laser directed energy deposition field.
文摘This paper introduces the research and development of high strength A517Q developed by Baosteel for platform rack,with micro-alloying adding suitable quenching and tempering process,trial thickness of 127-178 mm high-strength A517Q.The trial plate crossing thickness has a uniform mechanical properties,yield strength greater than 700 MPa,tensile strength than 790 MPa,the Charpy impact than 90 J at-40℃,aging impact than 69 J,has high strength and excellent low temperature impact toughness,While the plate has excellent resistance to crack tearing ability of low-temperature,NDT is less than-45℃.The Developing heavy plates had been used for manufacturing racks of 200-foot jack-up offshore platform,the performance meeting the requirements of the ABS,CCS classification societies.
