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"It can be freely deformed according to the environment. Onceget wounded or shoot， the wound will heal automatically likeliquid，" which is the image of the amorphous alloy robot in thescience fiction movie "Terminator". It is amazing because its body ismade by a kind of material called amorphous alloy.
So is there existing such stuff in real life？ Yes， and it has beensuccessfully developed by scientists. US scientists predict that itcould cause the third revolution in the history of material application.
Amorphous； Alloys： Metal
Exterior， Glass Heart
From human's first discovery ofamorphous alloy （also known asmetallic glasses）， to extensive andin-depth research of it， it was onlya few decades. We can say thatit is a very young member in thefamily of metallic materials.
Amorphous alloy is a kind ofmetal alloy obtained by meltinga variety of mixed elements. Ithas opaque nature， electricalconductivity， thermal conductivity，etc.， of the metal， with a clearmetallic luster； and high-strength，hardness and structural featuresintrinsic nature of glass. Therefore，it is also called as metallic glass orliquid metal.
It has the appearance ofmetal， but also deep with a heart ofqlass， combininq the advantaqesof both， but also toovercomina theshortcomings of thetwo， hence knownas the unbroken"King of glass" that cannever be smashed.
Preparation Tips： CoolDown Faster
It was until the 1960s， that DuWeizi and other US scientistssuccessively made amorphousalloy. It was discovered so late，mainly due to the fact that itsmethod of development is veryspecial.
After melting in hightemperature， metals condensenaturally， resulting in ordinarymetal of crystalline shape [atomicarrangement shown in picture（a）]. If the cooling rate of themelting process is acceleratedartificially， e.g. approaching 10，000o C per second or faster， thenthe amorphous alloy is obtained[atomic arrangement in picture （b）]
So， there is only one trick forpreparing amorphous alloys： cooldown faster！ High amorphousalloy by rapid coolingis of great strength，hardness， wearresistance， corrosionresistance， goodelasticity... Moreover， itsmost magic part is its thermoplasticwhich makes it soften like glass orplastic once heated.
Stretch the Noodles，Blow the Balloon
Amorphous alloy is thermoplastic，which at a certain temperature（the temperature range is calledsupercooled liquid region）， will beable to deform freely according to theneeds of people， just like the robtot inthe movie "Terminator". Using the thermoplastic ofamorphous alloy， we can make itlonger like stretching noodles [seeFig. （c）， we can also blow it into aspherical vessel like blowing a balloon[see Fig. （e）]. In addition， it can alsofreely deform in boiling water， and youcan print a variety of patterns on itssurface.
"Micro-shaped" Gizmo
The uniquethermoplastic ofamorphousalloy， is notonly ableto formthe macroscopicscale， but also isbetter at formingmicrostructure frommicron to nanometerscale. It is alsoknown as the "idealmicro and nanomoldina material."
Compared with the conventional moldingmaterials and micromachining technology， it has ahigh preparation efficiency （molding cycle in seconds，typically less than half a minute）， good precision offorming （dimensional error of about 2 %0）， superiorsurface quality （surface roughness even smaller ataround 10 nm）， simple process and low cost， etc..
Using the method of Fig.（g）， we can print patternsvarious types of micro structure on the surface of theamorphous， such as round or elongated ones timesthinner than a human hair； "LOVE" pattern less thanhalf a millimeter； millet phone logo arrays of line sizesmaller than bacteria millet phone logo arrays， etc..With the rapid development of microelectroniccomponents and precision machinery， in the currenttrend of structure and device miniaturization， the formingof fine parts and products is becoming increasinglyimportant.
Famous scholar in the University of CambridgeA.L.Greer believes that one of amorphous alloys' mostpromising application in the future is the one in the microand nano molding process. Its excellent thermoplasticand formability make it available to be printed functionalmicrostructure on its surface， and in this case produce arange of related devices and products.
For example， embossing on its surface gratingstructure l/10 the size of a human hair， we can getgrating devices， which has a bright prospect in precisionanalytical instruments， creating lotus-shaped micro-nano composite structure on its surface， we can achievesuperhydrophobic self-cleaning effect similar to lotusleaves， and this surely have a promising prospectin anti-corrosion， anti-dirt， anti-water， anti-snow， oiltransportation， and new water transportation tools.
In addition， it has a very broad application prospectsin medicine， precision instruments， especially in theemerging micro-electromechanical systems （MEMS，Micro-Electro-Mechanical System） fields.
Amorphous alloy has characteristics of both metaland glass， solid and liquid and it is the "holder" of manyrecords. Its thermoplastic makes it able to be createdprecise fine structure with excellent dimensionalaccuracy on its surface. Thus， it was identified as "thebest micro and nano molding material."
（Editor in charge： Li Yinhui）
So is there existing such stuff in real life？ Yes， and it has beensuccessfully developed by scientists. US scientists predict that itcould cause the third revolution in the history of material application.
Amorphous； Alloys： Metal
Exterior， Glass Heart
From human's first discovery ofamorphous alloy （also known asmetallic glasses）， to extensive andin-depth research of it， it was onlya few decades. We can say thatit is a very young member in thefamily of metallic materials.
Amorphous alloy is a kind ofmetal alloy obtained by meltinga variety of mixed elements. Ithas opaque nature， electricalconductivity， thermal conductivity，etc.， of the metal， with a clearmetallic luster； and high-strength，hardness and structural featuresintrinsic nature of glass. Therefore，it is also called as metallic glass orliquid metal.
It has the appearance ofmetal， but also deep with a heart ofqlass， combininq the advantaqesof both， but also toovercomina theshortcomings of thetwo， hence knownas the unbroken"King of glass" that cannever be smashed.
Preparation Tips： CoolDown Faster
It was until the 1960s， that DuWeizi and other US scientistssuccessively made amorphousalloy. It was discovered so late，mainly due to the fact that itsmethod of development is veryspecial.
After melting in hightemperature， metals condensenaturally， resulting in ordinarymetal of crystalline shape [atomicarrangement shown in picture（a）]. If the cooling rate of themelting process is acceleratedartificially， e.g. approaching 10，000o C per second or faster， thenthe amorphous alloy is obtained[atomic arrangement in picture （b）]
So， there is only one trick forpreparing amorphous alloys： cooldown faster！ High amorphousalloy by rapid coolingis of great strength，hardness， wearresistance， corrosionresistance， goodelasticity... Moreover， itsmost magic part is its thermoplasticwhich makes it soften like glass orplastic once heated.
Stretch the Noodles，Blow the Balloon
Amorphous alloy is thermoplastic，which at a certain temperature（the temperature range is calledsupercooled liquid region）， will beable to deform freely according to theneeds of people， just like the robtot inthe movie "Terminator". Using the thermoplastic ofamorphous alloy， we can make itlonger like stretching noodles [seeFig. （c）， we can also blow it into aspherical vessel like blowing a balloon[see Fig. （e）]. In addition， it can alsofreely deform in boiling water， and youcan print a variety of patterns on itssurface.
"Micro-shaped" Gizmo
The uniquethermoplastic ofamorphousalloy， is notonly ableto formthe macroscopicscale， but also isbetter at formingmicrostructure frommicron to nanometerscale. It is alsoknown as the "idealmicro and nanomoldina material."
Compared with the conventional moldingmaterials and micromachining technology， it has ahigh preparation efficiency （molding cycle in seconds，typically less than half a minute）， good precision offorming （dimensional error of about 2 %0）， superiorsurface quality （surface roughness even smaller ataround 10 nm）， simple process and low cost， etc..
Using the method of Fig.（g）， we can print patternsvarious types of micro structure on the surface of theamorphous， such as round or elongated ones timesthinner than a human hair； "LOVE" pattern less thanhalf a millimeter； millet phone logo arrays of line sizesmaller than bacteria millet phone logo arrays， etc..With the rapid development of microelectroniccomponents and precision machinery， in the currenttrend of structure and device miniaturization， the formingof fine parts and products is becoming increasinglyimportant.
Famous scholar in the University of CambridgeA.L.Greer believes that one of amorphous alloys' mostpromising application in the future is the one in the microand nano molding process. Its excellent thermoplasticand formability make it available to be printed functionalmicrostructure on its surface， and in this case produce arange of related devices and products.
For example， embossing on its surface gratingstructure l/10 the size of a human hair， we can getgrating devices， which has a bright prospect in precisionanalytical instruments， creating lotus-shaped micro-nano composite structure on its surface， we can achievesuperhydrophobic self-cleaning effect similar to lotusleaves， and this surely have a promising prospectin anti-corrosion， anti-dirt， anti-water， anti-snow， oiltransportation， and new water transportation tools.
In addition， it has a very broad application prospectsin medicine， precision instruments， especially in theemerging micro-electromechanical systems （MEMS，Micro-Electro-Mechanical System） fields.
Amorphous alloy has characteristics of both metaland glass， solid and liquid and it is the "holder" of manyrecords. Its thermoplastic makes it able to be createdprecise fine structure with excellent dimensionalaccuracy on its surface. Thus， it was identified as "thebest micro and nano molding material."
（Editor in charge： Li Yinhui）