# SHS Produced TiB\({}_{2}\)-Si Powders for Selective Laser Melting of Ceramic-Based Composite
## 1 Introduction  
Recent progress in materials science and technology has established a new paradigm in producing visual models of 3D architectures by additive manufacturing (AM) or 3D printing. AM represents a continuously growing multi-billion-dollar industry and has a profound impact on society and culture [1; 2; 3] as this technology allows for the fabrication of precisely dimensioned high-value products with specified internal features without extensive tooling. The growing interest in the manufacturing of high-performance components for applications in biomedical, aerospace, and automotive industries exemplifies the need for development of high-temperature (HT) ceramic materials with the help of AM [4]. While still at its infancy, direct AM processing of ceramics or ceramic-based composites requires the development of specific precursor materials and procedures to sinter them. Thorough selection of feedstock powders, which highly affect structures, properties, and performance of final product, is urgently needed for the fabrication of defect-free, structurally sound, and reliable AM parts. An ability to add functionality requires not only the precise control over the process, but also the efficiency of powders used. Production of AM parts with consistent, repeatable, and predictable characteristics depends on input materials. Although a wide variety of available methods offer powerful features and impressive capabilities, one of the key hurdles impeding wider application of AM is the current severe limitation of materials feedstock suitable for direct or indirect AM processing [4; 5]. The main advantage of the direct AM route is a simultaneous combination of forming and densification steps, which allows generation of the final component without any post-treatment. The direct selective laser melting (SLM) is one of the most convenient and reliablemethods for producing polymer- and/or metal-matrix composites [3,4]. A relatively wide range of metallic powders has been developed for AM; however, there is a lack of ceramic or ceramic-based powders available for AM through SLM. The process of building defect-free dense ceramic parts by SLM remains challenging due to the extremely high melting point, poor thermal shock resistance, and low or no plasticity of ceramics [5,6]. Commonly, the components fabricated by the direct SLM exhibit a high level of porosity and poor mechanical properties. One of the approaches is combining ceramic particles with a metal/metalloid binder, which ideally represents core-shell structures with a ceramic core responsible for mechanical properties and a metallic shell needed for laser absorptivity and material ductility. Production of custom-made items of a high performance and economic efficiency necessitates the utilization of powdered feedstock, which meets the requirements posed by the AM process conditions [7]. Therefore, the development of powder materials with tailorable physical and chemical properties has attracted a great deal of attention in the research community and industry. The quality of the feedstock powders largely depends on manufacturing process. The alloy powders are mainly prepared with the help of either the gas atomization process, rotary atomization process, or plasma rotating electrode process (PREP) [8]. The importance of a cost-effective production of powders with controlled particle size distribution and purity is a driving force for the development of several innovative concepts. We report on the exploitation of the energy-efficient and time-saving method of self-propagating high-temperature synthesis (SHS) or combustion synthesis (CS) [9,10] to design and produce the ceramic-metal powders for AM process [11,12]. We demonstrate the \"pomegranate-like\" TiB\({}_{2}\)-Si powder particulates to be suitable for SLM of the ceramic-based composite of high ceramic fraction. The main characteristics of the feedstock materials, which govern the powders flowability during the layer building, include shape, size distribution, surface morphology, and composition [8].