Why are pieces of spaghetti generally broken into three to ten segments instead of two as one thinks?How can one obtain the desired number of fracture segments?To answer those questions,the fracture dynamics of a stra...Why are pieces of spaghetti generally broken into three to ten segments instead of two as one thinks?How can one obtain the desired number of fracture segments?To answer those questions,the fracture dynamics of a strand of spaghetti is modelled by elastic rod and numerically investigated by using finiteelement software ABAQUS.By data fitting,two relations are obtained:the number of fracture segments in terms of rod diameter-length ratio and fracture limit curvature with the rod diameter.Results reveal that when the length is constant,the larger the diameter and/or the smaller the diameter-length ratio D/L,the smaller the limit curvature;and the larger the diameter-length ratio D/L,the fewer the number of fractured segments.The relevant formulations can be used to obtain the desired number of broken segments of spaghetti by changing the diameter-to-length ratio.展开更多
Recently,there have been the increase of ship size and the development of oil and gas in arctic region.These trends have led to the requirements such as high strength,good toughness at low temperature and good weldabi...Recently,there have been the increase of ship size and the development of oil and gas in arctic region.These trends have led to the requirements such as high strength,good toughness at low temperature and good weldability.The high performance structural steels for shipbuilding and arctic offshore structure have been developed by our own micro-alloying and TMCP technologies.M-A constituent was precisely controlled in the both HAZ and base metal to get high toughness at low temperature.Also,the grain growth of austenite at HAZ was effectively suppressed by thermally stable TiN particles,leading to a good HAZ toughness.On the other hand,there has been the key issue of crack arrestability in large size container ship.The effect of joint design on crack arrestability was investigated to prevent a catastrophic failure along the block joint of hatch side coaming.A brittle crack arrest technique was developed without block joint shift,using an arrest weld in the end of hatch side coaming weld line.展开更多
基金supported by Xi’an University of Architecture and Technology(Grant No.002/2040221134).
文摘Why are pieces of spaghetti generally broken into three to ten segments instead of two as one thinks?How can one obtain the desired number of fracture segments?To answer those questions,the fracture dynamics of a strand of spaghetti is modelled by elastic rod and numerically investigated by using finiteelement software ABAQUS.By data fitting,two relations are obtained:the number of fracture segments in terms of rod diameter-length ratio and fracture limit curvature with the rod diameter.Results reveal that when the length is constant,the larger the diameter and/or the smaller the diameter-length ratio D/L,the smaller the limit curvature;and the larger the diameter-length ratio D/L,the fewer the number of fractured segments.The relevant formulations can be used to obtain the desired number of broken segments of spaghetti by changing the diameter-to-length ratio.
文摘Recently,there have been the increase of ship size and the development of oil and gas in arctic region.These trends have led to the requirements such as high strength,good toughness at low temperature and good weldability.The high performance structural steels for shipbuilding and arctic offshore structure have been developed by our own micro-alloying and TMCP technologies.M-A constituent was precisely controlled in the both HAZ and base metal to get high toughness at low temperature.Also,the grain growth of austenite at HAZ was effectively suppressed by thermally stable TiN particles,leading to a good HAZ toughness.On the other hand,there has been the key issue of crack arrestability in large size container ship.The effect of joint design on crack arrestability was investigated to prevent a catastrophic failure along the block joint of hatch side coaming.A brittle crack arrest technique was developed without block joint shift,using an arrest weld in the end of hatch side coaming weld line.
