Abstract: Provided is a method for forming a three dimensional article comprising the steps of: providing at least one electron beam source emitting an electron beam for at least one of heating or fusing said powder material, where said electron beam source comprises a cathode, an anode, and a grid between said cathode and anode; controlling the electron beam source in at least two modes during said formation of said three dimensional article; applying a predetermined accelerator voltage between said cathode and said anode; applying a predetermined number of different grid voltages between said grid and said cathode for producing a corresponding predetermined number of electron beam currents; and at least one of creating or updating a look-up table or mathematical function during one of the at least two modes, wherein said look-up table or mathematical function defines a relationship between a desired electron beam current and an applied grid voltage.

Abstract: Provided is a method for forming a three dimensional article comprising the steps of: providing at least one electron beam source emitting an electron beam for at least one of heating or fusing said powder material, where said electron beam source comprises a cathode, an anode, and a grid between said cathode and anode; controlling the electron beam source in at least two modes during said formation of said three dimensional article; applying a predetermined accelerator voltage between said cathode and said anode; applying a predetermined number of different grid voltages between said grid and said cathode for producing a corresponding predetermined number of electron beam currents; and at least one of creating or updating a look-up table or mathematical function during one of the at least two modes, wherein said look-up table or mathematical function defines a relationship between a desired electron beam current and an applied grid voltage.

Abstract: Provided is a method for forming a three dimensional article comprising the steps of: providing at least one electron beam source emitting an electron beam for at least one of heating or fusing said powder material, where said electron beam source comprises a cathode, an anode, and a grid between said cathode and anode; controlling the electron beam source in at least two modes during said formation of said three dimensional article; applying a predetermined accelerator voltage between said cathode and said anode; applying a predetermined number of different grid voltages between said grid and said cathode for producing a corresponding predetermined number of electron beam currents; and at least one of creating or updating a look-up table or mathematical function during one of the at least two modes, wherein said look-up table or mathematical function defines a relationship between a desired electron beam current and an applied grid voltage.

Abstract: The present invention relates to a method for forming a three-dimensional article through successively depositing individual layers of powder material that are fused together so as to form the article, said method comprising the steps of: providing at least one electron beam source emitting an electron beam for heating and/or fusing said powder material. Controlling the electron beam source in a first mode when said formation of said three dimensional article is in a first process step. Controlling said electron beam in a second mode when said formation of said three dimensional article is in a second process step, wherein in said first mode an electron beam current from said electron beam source is controlled in a feed-forward mode and in said second mode said electron beam current is controlled in a feed-back mode.

Abstract: The invention concerns an apparatus (1) for producing three-dimensional objects (6) layer by layer using a powdery material which can be solidified by irradiating it with a beam (4) of charged particles, said apparatus (1) comprising means for successive application of powder layers to a work table, and a radiation gun (3) for delivering said beam (4) of charged particles, wherein the inventive apparatus (1) comprises a powder-lifting detection device (10, 10a, 10b, 10c, 10d, 10e) capable of generating a signal (S) upon detection of lifting of powdery material from the working area (5).

Abstract: Provided is a method for forming a three dimensional article comprising the steps of: providing at least one electron beam source emitting an electron beam for at least one of heating or fusing said powder material, where said electron beam source comprises a cathode, an anode, and a grid between said cathode and anode; controlling the electron beam source in at least two modes during said formation of said three dimensional article; applying a predetermined accelerator voltage between said cathode and said anode; applying a predetermined number of different grid voltages between said grid and said cathode for producing a corresponding predetermined number of electron beam currents; and at least one of creating or updating a look-up table or mathematical function during one of the at least two modes, wherein said look-up table or mathematical function defines a relationship between a desired electron beam current and an applied grid voltage.

Abstract: The present invention relates to a method for forming a three-dimensional article through successively depositing individual layers of powder material that are fused together so as to form the article, said method comprising the steps of: providing at least one electron beam source emitting an electron beam for heating and/or fusing said powder material. Controlling the electron beam source in a first mode when said formation of said three dimensional article is in a first process step. Controlling said electron beam in a second mode when said formation of said three dimensional article is in a second process step, wherein in said first mode an electron beam current from said electron beam source is controlled in a feed-forward mode and in said second mode said electron beam current is controlled in a feed-back mode.

Abstract: The invention concerns an apparatus (1) for producing three-dimensional objects (6) layer by layer using a powdery material which can be solidified by irradiating it with a beam (4) of charged particles, said apparatus (1) comprising means for successive application of powder layers to a work table, and a radiation gun (3) for delivering said beam (4) of charged particles, wherein the inventive apparatus (1) comprises a powder-lifting detection device (10, 10 a, 10 b, 10 c, 10 d, 10 e) capable of generating a signal (S) upon detection of lifting of powdery material from the working area (5).

Abstract: The invention concerns a method for producing three-dimensional objects (6) layer by layer using a powdery material which can be solidified by irradiating it with a beam (4) of charged particles, which method comprises the following steps: successive application of powder layers to a working area (5), and fusing together successive layers of said three-dimensional object (6) by successively irradiating the powdery layers with said beam (4).

Abstract: The invention concerns a method for producing three-dimensional objects (6) layer by layer using a powdery material which can be solidified by irradiating it with a beam (4) of charged particles, which method comprises the following steps: successive application of powder layers to a working area (5), and fusing together successive layers of said three-dimensional object (6) by successively irradiating the powdery layers with said beam (4).