TECHNICAL FIELD

The present teachings relate generally to three-dimensional (3D) printing and, more particularly, to systems and methods for determining a temperature of an object printed by a 3D printer.

BACKGROUND

A 3D printing process builds a three-dimensional object from a computer-aided design (CAD) model, usually by successively depositing material layer upon layer. For example, a first layer may be deposited upon a substrate, and then a second layer may be deposited upon the first layer. The temperature of the first layer and the temperature of the material being deposited upon the first layer to form the second layer should each be within a predetermined range to enable the layers to properly bond together and have the desired properties.

Oftentimes, non-contact temperature sensors are used to monitor the temperature during the 3D printing process, so as to not obstruct or otherwise interfere with the 3D printing process. One type of non-contact temperature sensor that is used is called a pyrometer, which measures an emissivity of a surface of the object during the 3D printing process. The emissivity refers to an effectiveness of emitting heat energy as thermal radiation. The pyrometer has a memory with data stored therein that corresponds to the type of material being printed. Using the measured emissivity and the data corresponding to the type of material being printed, the pyrometer may determine (e.g., predict) the temperature of the object (e.g., using a look-up table).

However, the surface finish and/or the surface content of the material being printed may vary, which may cause the temperature determinations from the pyrometer to be inaccurate. Therefore, it would be beneficial to have an improved system and method for determining a temperature of an object printed by a 3D printer.

SUMMARY

The following presents a simplified summary in order to provide a basic understanding of some aspects of one or more embodiments of the present teachings. This summary is not an extensive overview, nor is it intended to identify key or critical elements of the present teachings, nor to delineate the scope of the disclosure. Rather, its primary purpose is merely to present one or more concepts in simplified form as a prelude to the detailed description presented later.

A system for determining a temperature of an object is disclosed. The system includes a three-dimensional (3D) printer configured to successively deposit a first layer of material, a second layer of material, and a third layer of material to form the object. The 3D printer is configured to form a recess in the second layer of material. The material is a metal. The system also includes a temperature sensor configured to be positioned at least partially with the recess and to have the third layer deposited thereon. The temperature sensor is configured to measure a temperature of the first layer of material, the second layer of material, the third layer of material, or a combination thereof.

A method for determining a temperature of an object is also disclosed. The method includes depositing a first layer of material onto a substrate using a three-dimensional (3D) printer. The method also includes positioning a temperature sensor on the first layer of material. The method also includes depositing a second layer of material onto the first layer of material and the temperature sensor using the 3D printer. The method also includes measuring a temperature of the first layer of material, the second layer of material, or both using the temperature sensor.

In another embodiment, the method includes depositing a first layer of material onto a substrate using a three-dimensional (3D) printer. The method also includes depositing a second layer of material onto the first layer of material using the 3D printer. The method also includes forming a recess in the second layer of material. The method also includes positioning a temperature sensor at least partially in the recess such that the temperature sensor is in contact with the first layer of material, the second layer of material, or both. The temperature sensor is a thermocouple that includes two electrical conductors that are made of different materials. The method also includes depositing a third layer of material onto the second layer of material and the temperature sensor using the 3D printer. The first layer of material, the second layer of material, and the third layer of material includes a metal. The method also includes measuring a temperature of the first layer of material, the second layer of material, the third layer of material, or a combination thereof using the temperature sensor.

An object printed by a three-dimensional (3D) printer is also disclosed. The object includes a plurality of layers of material printed by the 3D printer. The layers of material bond together to form the object as the layers of material cool and solidify after being printed by the 3D printer. The object also includes a temperature sensor placed in contact with one or more of the layers when the layers of material are being printed by the 3D printer. The temperature sensor remains in contact with the object after the layers of material cool and solidify to form the object. The temperature sensor is configured to measure a temperature of the object after the layers of material cool and solidify to form the object.

In another embodiment, the object includes a first layer of material printed by the 3D printer. The object also includes a second layer of material printed by the 3D printer onto the first layer of material. A recess is formed in the second layer of material. The object also includes a third layer of material printed by the 3D printer onto the second layer of material. The first, second, and third layers of material bond together to form the object as the first, second, and third layers of material cool and solidify after being printed by the 3D printer. The object also includes a first temperature sensor positioned at least partially within the recess when the first, second, and third layers of material are being printed by the 3D printer. The first temperature sensor remains positioned at least partially within the recess after the first, second, and third layers of material cool and solidify to form the object. The first temperature sensor is configured to measure a temperature of the object before and after the first, second, and third layers of material cool and solidify to form the object.

A method for determining a temperature of an object is also disclosed. The method includes printing the object using a three-dimensional (3D) printer. The method also includes measuring the temperature of the object using a first temperature sensor while the object is being printed by the 3D printer. The first temperature sensor is in contact with the object. The method also includes measuring the temperature of the object using the first temperature sensor after the object has been printed by the 3D printer.

A method for determining a temperature of an object is also disclosed. The method includes contacting the object with a first electrical conductor. A difference in electronegativity between the object and the first electrical conductor is greater than a predetermined value. The method also includes contacting the object or a substrate on which the object is positioned with a second electrical conductor. A difference in electronegativity between the object or the substrate and the second electrical conductor is less than the predetermined value. The method also includes connecting the first and second electrical conductors together. The method also includes measuring the temperature of the object using the first and second electrical conductors. The first and second electrical conductors form at least a portion of a thermocouple.

A method for determining a temperature differential between two portions of an object is also disclosed. The method includes contacting a first portion of the object with a first end of an electrical conductor. A difference in electronegativity between the object and the electrical conductor is greater than a predetermined value. The method also includes contacting a second portion of the object with a second end of the electrical conductor. The method also includes determining a temperature differential between the first and second portions of the object using the electrical conductor.

A method for determining a temperature differential between two portions of an object is also disclosed. The method includes contacting a first portion of the object with a first electrical conductor. A difference in electronegativity between the object and the first electrical conductor is greater than a predetermined value. The method also includes contacting a second portion of the object with a second electrical conductor. A difference in electronegativity between the object and the second electrical conductor is greater than the predetermined value. The method also includes connecting the first and second electrical conductors together. The method also includes determining a temperature differential between the first and second portions of the object using the first and second electrical conductors.

