Heated build platform and system for three dimensional printing methods

Abstract

An apparatus performing as a base for printing 3D objects using high temperature thermoplastics employing additive manufacturing methods is provided. The apparatus comprises a heated build platform, a thin removable plate secured on top of the build platform, a high temperature polymer coating applied over the removable plate, and surface treatment of high temperature polymer coating to maintain adhesion between 3D object and printing surface. Also, the removable plate has low coefficient of thermal expansion compared to build platform below it, for avoiding bowing of the plate as it is heated due to heated build platform, hence providing flat printing surface. The thin removable plate allows 3D objects to pop off the plate upon cooling, without damaging the polymer coating, the plate, or the object. It also allows for continuous operation of printing, while the plate is released for cooling, a new plate is installed for printing.

1 .- 18 . (canceled) 
     
     
         19 . A build apparatus for printing a three-dimensional (3D) object, comprising:
 a thermally conductive plate disposed adjacent to a build platform, wherein said thermally conductive plate is removable from said build platform, and wherein said thermally conductive plate is capable of (i) securing said 3D object during printing and (ii) permitting removal of said 3D object from said thermally conductive plate once said 3D object has been formed, which removal is without chemically or mechanically removing material from said 3D object and without damaging said thermally conductive plate or said 3D object.   
     
     
         20 . The build apparatus of  claim 19 , further comprising a temperature control unit configured to control heating of said build platform. 
     
     
         21 . The build apparatus of  claim 20 , further comprising a ceramic or high temperature dielectric that insulates said build platform. 
     
     
         22 . The build apparatus of  claim 20 , wherein said temperature control unit comprises heater cartridges that are spaced along a surface of said build platform. 
     
     
         23 . The build apparatus of  claim 20 , wherein said temperature control unit comprises a heater and/or temperature sensor. 
     
     
         24 . The build apparatus of  claim 20 , wherein said build platform comprises thermocouples situated at one or several locations to provide feedback to a controller for maintaining temperature set points. 
     
     
         25 . The build apparatus of  claim 20 , wherein said build platform comprises a material selected from the group consisting of aluminum, steel, brass, ceramic, glass, and an alloy with a low coefficient of thermal expansion (CTE). 
     
     
         26 . The build apparatus of  claim 20 , wherein said build platform comprises a ceramic material. 
     
     
         27 . The build apparatus of  claim 20 , wherein said build platform has a first coefficient of thermal expansion (CTE) and said thermally conductive plate has a second CTE, wherein said first CTE is greater than said second CTE. 
     
     
         28 . The build apparatus of  claim 19 , further comprising a polymer coating that is capable of facilitating adhesion to said 3D object during printing. 
     
     
         29 . The build apparatus of  claim 28 , wherein said polymer coating is a polyimide. 
     
     
         30 . The build apparatus of  claim 28 , wherein said polymer coating comprises a thickness ranging between 0.001 inches and 0.1 inches. 
     
     
         31 . The build apparatus of  claim 28 , wherein a surface of said polymer coating includes nano-, micro-, or milli-meter scale features that increase adhesion to said 3D object. 
     
     
         32 . The build apparatus of  claim 28 , wherein said thermally conductive plate is flexible so as to allow for easier dissociation between said 3D object and said thermally conductive plate upon cooling and reduce damage to said polymer coating or said 3D object during removal of said 3D object. 
     
     
         33 . The build apparatus of  claim 28 , wherein said build platform, said thermally conductive plate, and said polymer coating are able to withstand high temperature ranging between 150 degree Celsius and 300 degree Celsius. 
     
     
         34 . The build apparatus of  claim 19 , wherein said thermally conductive plate comprises a material selected from the group consisting of aluminum, steel, brass, ceramic, glass, and an alloy with a low coefficient of thermal expansion (CTE). 
     
     
         35 . The build apparatus of  claim 19 , wherein said thermally conductive plate comprises a thickness ranging between 0.025 inches and 0.5 inches, wherein said thickness depends on a flexural character of said material. 
     
     
         36 . The build apparatus of  claim 19 , wherein said thermally conductive plate is non-magnetically secured to and removable from said build platform. 
     
     
         37 . The build apparatus of  claim 19 , further comprising a component selected from the group consisting of guiding legs, guiding rails, spring, latch, a means for providing vacuum suction, magnets, and electromagnets to secure and remove said thermally conductive plate. 
     
     
         38 . The build apparatus of  claim 19 , wherein said build platform comprises holes for heater cartridges and thermocouples. 
     
     
         39 . The build apparatus of  claim 19 , wherein said thermally conductive plate is vacuum suctioned onto said build platform.