ORIGINAL ARTICLE Fabrication and control of a microheater array for Microheater Array Powder Sintering Nicholas Holt 1 & Lucas Galvan Marques 1 & Austin Van Horn 1 & Mahsa Montazeri 1 & Wenchao Zhou 1 Received: 25 June 2017 /Accepted: 2 November 2017 # Springer-Verlag London Ltd., part of Springer Nature 2017 Abstract Microheater Array Powder Sintering (MAPS) is a novel additive manufacturing process that uses a microheater array to replace the laser of selective laser sintering as the energy source. Most of the previous research on microheaters is for applications in gas sensing or inkjet printing. The oper- ation temperature and response time of the microheater array are critical for the choice of sintering materials and printing speed for the MAPS process. This paper presents the fabrica- tion, packaging, and control of a platinum microheater array that has a target operation temperature of 400 °C and a re- sponse time of ~ 1 ms for the MAPS process. First, the fabri- cation process of a microheater array is presented. The fabri- cated microheater array was packaged for easy control and to serve as the printhead of the MAPS process. A proportional- integral-derivative controller was designed to control the tem- perature response of the microheater. Finally, the effectiveness of the controller was evaluated. Results show the fabricated microheater array is capable of reaching the target temperature of 400 °C and has a thermal response time of less than 1 ms, which satisfies the design requirements for the MAPS process. Keywords Additive manufacturing . MAPS . Microheaters . MEMS . PID controls 1 Introduction Microheater Array Powder Sintering (MAPS) is an emerging additive manufacturing (AM) technology which selectively sinters powder particles with a microheater array. In contrast to selective laser sintering (SLS) which uses an expensive laser to scan a powder bed pointwise to fuse particles, MAPS uses an array of microheaters as an energy source to deliver a heat pattern by bringing the microheater array in close proximity to a powder bed to sinter powder particles in a layer-wise fashion as illustrated in Fig. 1 [1, 2]. MAPS promises significant increase in printing speed by increasing the number of microheaters and great energy savings because a microheater typically operates with a power of ~ 1 watt (compared to a laser usually around ~ 100 watts in selective laser sintering (SLS)). To maximize the potential of the MAPS technology, the microheater array needs to satisfy several requirements: (1) Each microheater element in the microheater array needs to be able to deliver sufficient energy to sinter powder particles at a speed on par with that of a laser; (2) Each microheater ele- ment needs to be individually operated at a timescale (i.e., the timescale of the heating and cooling cycle) shorter than the sintering timescale; (3) The microheater array needs to be fabricated in a cost-efficient manner and be scalable to a large number of microheater elements at minimal additional cost; (4) The packaging of the microheater array should be designed such that nothing protrudes from the microheater surface to avoid interference with the MAPS process; (5) The tempera- ture of the microheater needs to be precisely controlled, and the temperature distribution in the microheater needs to be as even as possible for consistent sintering quality. As will be revealed in our literature review in the next section, microheaters have been typically used in gas sensing and thermal inkjet printing applications. No research has been reported on designing, fabricating, packaging, and controlling a microheater array that can satisfy the requirements for the MAPS process. In this paper, a microheater printhead for the MAPS process, which includes the fabrication, packaging, * Wenchao Zhou zhouw@uark.edu 1 The AM³ Lab, Department of Mechanical Engineering, University of Arkansas at Fayetteville, Fayetteville, AR, USA Int J Adv Manuf Technol https://doi.org/10.1007/s00170-017-1316-8