Device and method for making a three-dimensional object

Abstract

A device for the making of a three-dimensional object ( 3 ) by means of layer by layer consolidation of a powderlike construction material ( 11 ) by electromagnetic radiation or particle beam has a height-adjustable carrier ( 2 ), on which the object ( 3 ) is built, and whose horizontal dimension defines a construction field ( 5 ). Furthermore, an irradiation device ( 6, 9 ) is present for directing the radiation onto regions of an applied layer of the construction material within the construction field ( 5 ) corresponding to an object cross section ( 30 ). A control unit ( 10 ) controls the irradiation device ( 6, 9 ) such that the powder particles of the construction material ( 11 ) are bonded together at the sites where the radiation impinges on the construction material. A selective heating device ( 18 a, 18 b ) is designed so that any given partial surface ( 19 ) of the construction field ( 5 ) can be heated before and/or after to a plateau temperature, which is significantly higher than the temperature of at least a portion of the construction field ( 5 ) outside the partial surface ( 19 ). The control unit ( 10 ) actuates the selective heating device ( 18 a, 18 b ) such that the partial surface ( 19 ) has a predefined minimum distance (d) from the edge of the construction field ( 5 ).

1 . Device for the making of a three-dimensional object by means of layer by layer consolidation of a powderlike construction material by electromagnetic radiation or particle radiation with:
 a height-adjustable carrier, on which the object is built, and whose horizontal dimension defines a construction field,   an irradiation device for directing the electromagnetic radiation or particle radiation onto regions of an applied layer of the construction material within the construction field corresponding to an object cross section,   a control unit for controlling the irradiation device such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized by a selective heating device, which is designed so that any given partial surface of the construction field can be heated to a plateau temperature, which plateau temperature is significantly higher than the temperature of at least a portion of the construction field outside the partial surface, wherein the control unit is designed so that it actuates the selective heating device such that the partial surface has a predefined minimum distance from the edge of the construction field.   
     
     
         2 . Device according to  claim 1 , wherein the plateau temperature is at most 200° C. less than an activation temperature of the construction material. 
     
     
         3 . Device according to  claim 1 , wherein
 the control unit has a data storage, in which material parameter values with regard to a thermal behaviour of at least one construction material, preferably various construction materials, are stored.   
     
     
         4 . Device according to  claim 3 , wherein
 the control unit in operation establishes the minimum distance in dependence on the material parameter values stored in the data storage for the construction material being used.   
     
     
         5 . Device according to  claim 1 , wherein the control unit in operation establishes the shape of the partial surface in dependence on the shape of the object cross section to be consolidated. 
     
     
         6 . Device according to  claim 1 , wherein the control unit in operation establishes the partial surface such that its area extent is greater than that of the object cross section to be consolidated. 
     
     
         7 . Device according to  claim 1 , wherein the selective heating device in operation directs electromagnetic radiation, especially laser radiation, and/or particle radiation onto the surface of the construction material. 
     
     
         8 . Device according to  claim 7 , wherein the irradiation device directs laser radiation onto the surface of the construction material and the laser radiation of the selective heating device has the same wavelength as that of the irradiation device. 
     
     
         9 . Device according to  claim 1 , further comprising a container surrounding the construction field, wherein the device comprises a cooling and/or heating device for the cooling and/or heating of the container. 
     
     
         10 . Device according to  claim 1 , further comprising a temperature measuring device, wherein the control unit in operation controls the heat supply by the selective heating device so that a minimum plateau temperature to which the partial surface of the construction field is heated in at least one operating state is by a predetermined amount above a temperature relayed by the temperature measuring device to the control unit. 
     
     
         11 . Device according to  claim 10 , wherein the control unit controls the selective heating device so that the partial surface is preheated to a minimum plateau temperature which lies at least 300° C. above the temperature relayed by the temperature measuring device to the control unit. 
     
     
         12 . Device according to  claim 1 , wherein the control unit actuates the selective heating device so that it heats a partial surface of the construction field after the directing of the electromagnetic radiation or particle radiation onto the construction material by the irradiation device such that a cooldown rate in the partial surface is at least 30% less than without the action of the selective heating device, wherein the partial surface has a predefined minimum distance from the edge of the construction field. 
     
     
         13 . Method for making a three-dimensional object by means of a layer by layer consolidation of a powderlike construction material by electromagnetic radiation or particle radiation in a device, according to  claim 1 ,
 wherein an object is built on a height-adjustable carrier, whose horizontal dimension defines a construction field,   wherein the electromagnetic radiation or particle radiation is directed with the aid of an irradiation device onto regions of a deposited layer of the construction material within the construction field that correspond to an object cross section,   wherein the irradiation device is controlled with a control unit such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized in that, with a selective heating device, any given partial surface of the construction field is heated to a plateau temperature, which plateau temperature is significantly higher than a temperature of at least a portion of the construction field outside the partial surface, wherein the control unit actuates the selective heating device so that the partial surface has a predefined minimum distance from the edge of the construction field.   
     
     
         14 . Method according to  claim 13 , wherein the minimum distance is established in dependence on preliminary experiments in which the heat transmission ability of the construction material used in the method is determined. 
     
     
         15 . Method according to  claim 14 , wherein the control unit actuates the selective heating device so that the latter heats the partial surface of the construction field at least to the plateau temperature before and/or after the directing of the electromagnetic radiation or particle radiation onto the construction material by the irradiation device, wherein the partial surface has a predefined minimum distance from the edge of the construction field. 
     
     
         16 . Device according to  claim 3 , with a temperature measuring device, wherein the control unit in operation controls the heat supply by the selective heating device so that a minimum plateau temperature to which the partial surface of the construction field is heated in at least one operating state is by a predetermined amount above a temperature relayed by the temperature measuring device to the control unit. 
     
     
         17 . Method for making a three-dimensional object by means of a layer by layer consolidation of a powder like construction material by electromagnetic radiation or particle radiation in a device, especially according to  claim 3 ,
 wherein an object is built on a height-adjustable carrier, whose horizontal dimension defines a construction field,   wherein the electromagnetic radiation or particle radiation is directed with the aid of an irradiation device onto regions of a deposited layer of the construction material within the construction field that correspond to an object cross section,   wherein the irradiation device is controlled with a control unit such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized in that, with a selective heating device, any given partial surface of the construction field is heated to a plateau temperature, which plateau temperature is significantly higher than a temperature of at least a portion of the construction field outside the partial surface, wherein the control unit actuates the selective heating device so that the partial surface has a predefined minimum distance from the edge of the construction field.   
     
     
         18 . Method for making a three-dimensional object by means of a layer by layer consolidation of a powder like construction material by electromagnetic radiation or particle radiation in a device, especially according to  claim 5 ,
 wherein an object is built on a height-adjustable carrier, whose horizontal dimension defines a construction field,   wherein the electromagnetic radiation or particle radiation is directed with the aid of an irradiation device onto regions of a deposited layer of the construction material within the construction field that correspond to an object cross section,   wherein the irradiation device is controlled with a control unit such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized in that, with a selective heating device, any given partial surface of the construction field is heated to a plateau temperature, which plateau temperature is significantly higher than a temperature of at least a portion of the construction field outside the partial surface, wherein the control unit actuates the selective heating device so that the partial surface has a predefined minimum distance (d) from the edge of the construction field.   
     
     
         19 . Method for making a three-dimensional object by means of a layer by layer consolidation of a powder like construction material by electromagnetic radiation or particle radiation in a device, especially according to  claim 6 ,
 wherein an object is built on a height-adjustable carrier, whose horizontal dimension defines a construction field,   wherein the electromagnetic radiation or particle radiation is directed with the aid of an irradiation device onto regions of a deposited layer of the construction material within the construction field that correspond to an object cross section,   wherein the irradiation device is controlled with a control unit such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized in that, with a selective heating device, any given partial surface of the construction field is heated to a plateau temperature, which plateau temperature is significantly higher than a temperature of at least a portion of the construction field outside the partial surface, wherein the control unit actuates the selective heating device so that the partial surface has a predefined minimum distance from the edge of the construction field.   
     
     
         20 . Method for making a three-dimensional object by means of a layer by layer consolidation of a powder like construction material by electromagnetic radiation or particle radiation in a device, especially according to  claim 10 ,
 wherein an object is built on a height-adjustable carrier, whose horizontal dimension defines a construction field,   wherein the electromagnetic radiation or particle radiation is directed with the aid of an irradiation device onto regions of a deposited layer of the construction material within the construction field that correspond to an object cross section,   wherein the irradiation device is controlled with a control unit such that the powder particles of the construction material are bonded together at the sites where the electromagnetic radiation or particle radiation impinges on the construction material,   characterized in that, with a selective heating device, any given partial surface of the construction field is heated to a plateau temperature, which plateau temperature is significantly higher than a temperature of at least a portion of the construction field outside the partial surface, wherein the control unit actuates the selective heating device so that the partial surface has a predefined minimum distance from the edge of the construction field.