Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform geometries.In this work,two different kinds ...Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform geometries.In this work,two different kinds of Fe_(41)Co_(7)Cr_(15)Mo_(14)C_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAM technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating C obtained by air-sweep annealing of B with a low energy-density laser.The morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed structure.Cracking was suppressed in coating C,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous content.Finally,the internal friction behavior of a BMGcs was prepared on the basis of the process of sample C is compared with that of as-cast amorphous alloys.The results show that the low temperature internal friction behavior of BMGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.展开更多
With the rapid development of medical technology,3D printing technology with realistic representation can perfectly display static human anatomy,while 3D visualisation technology based on Web Graphics Library(WebGL)ca...With the rapid development of medical technology,3D printing technology with realistic representation can perfectly display static human anatomy,while 3D visualisation technology based on Web Graphics Library(WebGL)can promote the rigid replication characteristics of traditional teaching models and express the dynamic spatial relationship between different anatomical structures.Medical students traditionally have less cognition of ankle ligament sprains.In this study,computed tomography(CT)and magnetic resonance imaging(MRI)data of the ankle joints of volunteers were used to print models of the ankle bone,tendon,and ligament using 3D printing technology,and a real-time interactive 3D digital model of the functional ankle joint was designed using 3D visualisation based on WebGL and 2D image real-time rendering technology for interactive teaching.The utility of the 3D printing model combined with the WebGL-based 3D digital teaching model was evaluated in comparison with traditional teaching methods in 24 medical students.The results showed that the total score of students in the experimental group(mean±SD,79.48±12.93)was significantly better than that of the control group(61.00±14.94)with P<0.05.The practical test scores of the experimental group(18.00±2.70)were significantly higher than those of the control group(13.67±4.96)with P<0.05.In the satisfaction survey,the feedback questionnaire showed that the interactive teaching model of 3D printing technology combined with WebGL-based 3D visualisation technology was recognised by students in terms of quality and overall satisfaction.In addition,female students who used 3D printing combined with WebGL-based 3D visualisation technology as learning aids had a greater difference in practical test scores from the control group than male students.This study has demonstrated that the interactive teaching mode of 3D printing combined with WebGL-based 3D visualisation technology is beneficial to the teaching of medical imaging,enriching the learning experience of students,and increasing the interaction between teachers and students.展开更多
本文首先指出了传统过程流体机械教育存在的弊端,其次在传统教学模式基础上引出了微课教学模式,并分析了微课教学模式在过程流体机械教学中的可行性,最后结合solidworks建立的三维机械仿真模型、3D模型打印技术以及Adobe Premiere Pro C...本文首先指出了传统过程流体机械教育存在的弊端,其次在传统教学模式基础上引出了微课教学模式,并分析了微课教学模式在过程流体机械教学中的可行性,最后结合solidworks建立的三维机械仿真模型、3D模型打印技术以及Adobe Premiere Pro CC软件编辑介绍了微课在流体机械教学中的运用。展开更多
Highlights Amid rapid technological development in the Fourth Industrial Revolution,this article engages with an important question,especially in the context of science,technology,engineering,and mathematics(STEM)educ...Highlights Amid rapid technological development in the Fourth Industrial Revolution,this article engages with an important question,especially in the context of science,technology,engineering,and mathematics(STEM)education:Can technology transform STEM teaching and learning?展开更多
基金This work was supported by the National Natural Science Foundation of China(No.52161028)the Major Discipline Academic and Technical Leaders Training Program of Jiangxi Province(No.20213BCJ22017).
文摘Laser 3D printing,also known as laser additive manufacturing(LAM),is favored for its ability to form bulk metallic glass(BMG)and its composite materials(BMGcs)with freeform geometries.In this work,two different kinds of Fe_(41)Co_(7)Cr_(15)Mo_(14)C_(15)B_(6)Y_(2)amorphous coatings(A and B)were prepared by using LAM technology under air-and water-cooled conditions,respectively;meanwhile,to reduce the cracks generated due to the residual thermal stresses,coating C obtained by air-sweep annealing of B with a low energy-density laser.The morphology and amorphous content and microstructure of the coatings were investigated,the results show many cracks in coating B deposited under water-cooled conditions,and its microstructure shows an amorphous-crystal-nanocrystalline mixed structure.Cracking was suppressed in coating C,obtained by air-sweep annealing based on coating B,but the amorphous content was reduced from 32.6 to 13.4%.And the hardness and corrosion resistance of the coating will increase with the increase in the amorphous content.Finally,the internal friction behavior of a BMGcs was prepared on the basis of the process of sample C is compared with that of as-cast amorphous alloys.The results show that the low temperature internal friction behavior of BMGcs is affected by the defects produced during printing,and the high temperature internal friction behavior is affected by the precipitated hard phase.
基金the Clinical Research Plan of SHDC(No.SHDC2020CR3083B)the Technology Project of Shanghai Science and Technology Commission(Nos.19441902700,and 18441903100)the Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support(No.20152221)。
文摘With the rapid development of medical technology,3D printing technology with realistic representation can perfectly display static human anatomy,while 3D visualisation technology based on Web Graphics Library(WebGL)can promote the rigid replication characteristics of traditional teaching models and express the dynamic spatial relationship between different anatomical structures.Medical students traditionally have less cognition of ankle ligament sprains.In this study,computed tomography(CT)and magnetic resonance imaging(MRI)data of the ankle joints of volunteers were used to print models of the ankle bone,tendon,and ligament using 3D printing technology,and a real-time interactive 3D digital model of the functional ankle joint was designed using 3D visualisation based on WebGL and 2D image real-time rendering technology for interactive teaching.The utility of the 3D printing model combined with the WebGL-based 3D digital teaching model was evaluated in comparison with traditional teaching methods in 24 medical students.The results showed that the total score of students in the experimental group(mean±SD,79.48±12.93)was significantly better than that of the control group(61.00±14.94)with P<0.05.The practical test scores of the experimental group(18.00±2.70)were significantly higher than those of the control group(13.67±4.96)with P<0.05.In the satisfaction survey,the feedback questionnaire showed that the interactive teaching model of 3D printing technology combined with WebGL-based 3D visualisation technology was recognised by students in terms of quality and overall satisfaction.In addition,female students who used 3D printing combined with WebGL-based 3D visualisation technology as learning aids had a greater difference in practical test scores from the control group than male students.This study has demonstrated that the interactive teaching mode of 3D printing combined with WebGL-based 3D visualisation technology is beneficial to the teaching of medical imaging,enriching the learning experience of students,and increasing the interaction between teachers and students.
基金supported by the Research Grant Council of Hong Kong,Early Career Scheme (ECS Ref#24615919).
文摘Highlights Amid rapid technological development in the Fourth Industrial Revolution,this article engages with an important question,especially in the context of science,technology,engineering,and mathematics(STEM)education:Can technology transform STEM teaching and learning?