The amorphization of alloys is of both broad scientific interests and engineering significance.Despite considered as an efficient strategy to regulate and even achieve record-breaking properties of metallic materials,...The amorphization of alloys is of both broad scientific interests and engineering significance.Despite considered as an efficient strategy to regulate and even achieve record-breaking properties of metallic materials,a facile and rapid method to trigger solid-state amorphization is still being pursued.Here we report such a method to utilize ultrasonic vibration to trigger amorphization of intermetallic compound.The ultrasonic vibrations can cause tunable amorphization at room temperature and low stress(2 MPa)conveniently.Remarkably,the ultrasonic-induced amorphization could be achieved in 60 s,which is 360 times faster than the ball milling(2.16×10^(4) s)with the similar proportion of amorphization.The elements redistribute uniformly and rapidly via the activated short-circuit diffusion.Both experimental evidences and simulations show that the amorphous phase initiates and expands at nanograin boundaries,owing to the induction of lattice instability.This work provides a groundbreaking strategy for developing novel materials with tunable structures and properties.展开更多
Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming o...Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming of long-term aged MGs.Here,we report ultrasonic vibration(UV)loading can lead to large plas-ticity and strong rejuvenation in significantly aged MGs within 1 s.A large UV-induced plasticity(UVIP)of 80%height reduction can be achieved in LaNiAl MG samples aged at 85%of its glass transition tem-perature(0.85 T_(g))for a duration of up to 1 month.The energy threshold required for UVIP monotonously increases with aging time.After the UV loading process,the aged samples show strong rejuvenation,with the relaxation enthalpy even surpassing that of as-cast samples.These findings suggest that UV loading is an effective technique for forming and rejuvenating aged MGs simultaneously,providing an alterna-tive avenue to explore the interplay between the property and microstructures as well as expanding the application prospects of MGs.展开更多
Glass-forming ability is a long-standing concern in the field of metallic glasses(MGs),which greatly limits their maximum casting size and extensive applications.In this work,we report an ultrasonic-assisted rapid col...Glass-forming ability is a long-standing concern in the field of metallic glasses(MGs),which greatly limits their maximum casting size and extensive applications.In this work,we report an ultrasonic-assisted rapid cold welding of bulk MGs without using any additives.MGs with various compositions are welded together under a 20,000-Hz highfrequency ultrasonic vibration without losing their amorphous nature.The ultrasonic technology offers the advantages of rapid bonding(<1 s)at low temperature(near room temperature)and low stress(<1 MPa).According to the phenomenon observed in the experiment,the activated fresh atoms diffuse through the broken channel port under continuous rupture of the oxide layer,and the ultrasonic vibration accelerates the atomic-diffusion process.Finally,stable bonding of the MG interface is realized.This universal ultrasonic-assisted welding process can realize the composition design of dissimilar MGs as well as tuning of new materials with new performance.展开更多
基金financially supported by the Key Basic and Applied Research Program of Guangdong Province,China(No.2019B030302010)the National Natural Science Foundation of China(Nos.52122105,51971150,51871157)+3 种基金the National Key Research and Development Program of China(No.2018YFA0703605)the financial support from the National Natural Science Foundation of China(No.12072344)the Youth Innovation Promotion Association of the Chinese Academy of Sciencessupported by the Beijing Electron Positron Collider(BEPC)project(No.2020-BEPC-PT-004661).
文摘The amorphization of alloys is of both broad scientific interests and engineering significance.Despite considered as an efficient strategy to regulate and even achieve record-breaking properties of metallic materials,a facile and rapid method to trigger solid-state amorphization is still being pursued.Here we report such a method to utilize ultrasonic vibration to trigger amorphization of intermetallic compound.The ultrasonic vibrations can cause tunable amorphization at room temperature and low stress(2 MPa)conveniently.Remarkably,the ultrasonic-induced amorphization could be achieved in 60 s,which is 360 times faster than the ball milling(2.16×10^(4) s)with the similar proportion of amorphization.The elements redistribute uniformly and rapidly via the activated short-circuit diffusion.Both experimental evidences and simulations show that the amorphous phase initiates and expands at nanograin boundaries,owing to the induction of lattice instability.This work provides a groundbreaking strategy for developing novel materials with tunable structures and properties.
基金supported by the Key Basic and Applied Research Program of Guangdong Province,China(Grant No.2019B030302010)the NSF of China(Grant Nos.52122105,51971150,51901243)+1 种基金the Science and Technology Innovation Commission Shenzhen(Grants No.RCJC20221008092730037 and 20220804091920001)the National Key Research and Development Program of China(Grant No.2018YFA0703605).
文摘Metallic glasses(MGs)possess exceptional properties,but their properties consistently deteriorate over time,thereby resulting in increased complexity in processing.It thus poses a formidable challenge to the forming of long-term aged MGs.Here,we report ultrasonic vibration(UV)loading can lead to large plas-ticity and strong rejuvenation in significantly aged MGs within 1 s.A large UV-induced plasticity(UVIP)of 80%height reduction can be achieved in LaNiAl MG samples aged at 85%of its glass transition tem-perature(0.85 T_(g))for a duration of up to 1 month.The energy threshold required for UVIP monotonously increases with aging time.After the UV loading process,the aged samples show strong rejuvenation,with the relaxation enthalpy even surpassing that of as-cast samples.These findings suggest that UV loading is an effective technique for forming and rejuvenating aged MGs simultaneously,providing an alterna-tive avenue to explore the interplay between the property and microstructures as well as expanding the application prospects of MGs.
基金supported by the Key Basic and Applied Research Program of Guangdong Province,China(2019B030302010)the National Natural Science Foundation of China(51871157,51971150 and 51775351)+2 种基金the Science and Technology Innovation Commission Shenzhen(JCYJ20170412111216258)the National Key Research and Development Program of China(2018YFA0703605)Shenzhen Basic Research Project(JCYJ20190808152409578).
文摘Glass-forming ability is a long-standing concern in the field of metallic glasses(MGs),which greatly limits their maximum casting size and extensive applications.In this work,we report an ultrasonic-assisted rapid cold welding of bulk MGs without using any additives.MGs with various compositions are welded together under a 20,000-Hz highfrequency ultrasonic vibration without losing their amorphous nature.The ultrasonic technology offers the advantages of rapid bonding(<1 s)at low temperature(near room temperature)and low stress(<1 MPa).According to the phenomenon observed in the experiment,the activated fresh atoms diffuse through the broken channel port under continuous rupture of the oxide layer,and the ultrasonic vibration accelerates the atomic-diffusion process.Finally,stable bonding of the MG interface is realized.This universal ultrasonic-assisted welding process can realize the composition design of dissimilar MGs as well as tuning of new materials with new performance.
