Abstract
Resistance heating metal wire materials additive manufacturing technology is of great significance for space environment maintenance and manufacturing. However, the continuous deposition process has a problem in which the metal melt is disconnected from the base metal. In order to study the difference between the second contact melting of the disconnected metal melt and the continuous melting of the metal wire as well as eliminate the problem of the uneven heat dissipation of the base metal deposition on the melting process of the metal wire, the physical test of melting the metal wire clamped by the equal diameter conductive nozzle was carried out from the aspects of temperature distribution, temperature change, melting time, dynamic resistance change, and the microstructure. The current, wire length, and diameter of the metal wire are used as variables. It was found that the dynamic resistance change of the wire can be matched with the melting state. During the solid-state temperature rise, due to the presence of the contact interface, the continuous melting and secondary contact melting of metal wires differ in dynamic resistance and the melting process. The continuous melting of the metal wire was caused by the overall resistance of the wire to generate heat and melt, and the temperature distribution is “bow-shaped”. In the second contact melting, the heat generated by the contact interface resistance was transferred to both ends of the metal wire to melt, and the temperature distribution is “inverted V”. The microstructure of the metal wire continuous melting and secondary contact melting solidification is similar. The continuous melting length of the metal wire is greater than the melting length of the secondary contact.
Highlights
In-space metal materials’ additive manufacturing technology has been applied to the manufacture and repair of metal parts in the orbit
The heat sources used in metal additive manufacturing technology are mainly laser beams, electron beams, plasma beams, and arc beams [4,5]
In order to study the difference between the second contact melting of the disconnected metal melt and the continuous melting of the metal wire, the influence of uneven heat the base metal deposition on the melting process of the metal wire is avoided
Summary
In-space metal materials’ additive manufacturing technology has been applied to the manufacture and repair of metal parts in the orbit. Metal wire additive manufacturing technology using a laser beam as a heat source has the advantages of high energy density, high precision, high efficiency, and high flexibility [8,9]. In this approach, the device structure is relatively complicated, the power output is high, and the energy utilization rate is relatively low. The electrical energy is converted into Joule heating by the current, and the wire was melted and shaped This method has the advantages of high thermal efficiency, precise heat input control, and simple additive manufacturing equipment [15,16,17]. The research is carried out from the aspects of temperature distribution, temperature change, melting time, dynamic resistance change, and microstructure
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
