Near net-shape, ultra-high melting, recession-resistant ZrC/W-based rocket nozzle liners via the displacive compensation of porosity (DCP) method

Experimental set up for characterization of carbide-based materials in propulsion environment

“…This work is focused on the development and testing of monolithic composites based on carbides of early transition metals, in particular tantalum carbide. [3][4][5] Ultra High Temperature Ceramics (UHTC) such as Tantalum Carbide (TaC) and Hafnium Carbide (HfC) are very good potential candidate materials for use in propulsive systems. These compounds possess an excellent combination of properties including extremely high melting point (3950 • C and 3928 • C, respectively), high electrical and thermal conductivity, good thermal shock resistance and superior ablation resistance compared to C/C composites.…”

Microstructure and properties of W–ZrC composites prepared by the displacive compensation of porosity (DCP) method

“…Zirconium carbide, for its extremely high melting temperature (3540 • C), relatively low density ( [ZrC] = 6.63 g/cm 3 , one third of [W]), good ablation resistance [4][5][6], and being consistent with tungsten [7,8], has been introduced into the refractory metal [4,6,7]. Furthermore, composites of these two materials can improve the flexural strength of tungsten and the fracture toughness of zirconium carbide at elevated temperature [9,10].…”

“…In this process, a solid-state reaction between ZrO 2 and WC was used, and ZrC powder was added to adjust the microstructure. Recently, a novel method for preparation the composites, known as the displacive compensation of porosity (DCP) method, was developed by Dickerson and Sandhage et al [7,[14][15][16]. The DCP method, in which a molten Zr 2 Cu alloy infiltrated into and then reacted with a porous WC perform at modest temperatures, was effective and promising for fabricating ZrC/W composites.…”

Near net-shape/net-dimension ZrC/W-based composites with complex geometries via rapid prototyping and Displacive Compensation of Porosity

“…24 Dickerson et al have used a reactive infiltration process to convert porous WC preforms into 96.5-99.6% dense ZrC/W-based composites containing 50-60 vol% ZrC with little change (<1%) in dimensions and shape. 25,26 This patented process, known as the Displacive Compensation of Porosity, involves the use of volume-increasing liquid/solid displacement reactions to fill the pores within rigid, shaped ceramic-bearing preforms. [27][28][29][30][31][32] The reactive (pressureless) infiltration of Zr 2 Cu(l) into rigid, porous WC preforms at 1150-1300 • C resulted in the formation of ZrC/W-based composites via the following displacement reaction:…”

“…[34][35][36][37] DCP-derived ZrC/W-based rocket nozzle liners, fabricated by reactive infiltration of a porous, nozzle-shaped WC preform prepared by gel casting, have been found to be resistant to the extreme thermal shock and erosion conditions of a solid-fueled Pi-K rocket test. 25 While gel casting is an effective and scalable method for fabricating complex-shaped 3D WC preforms, this casting process required the fabrication of a multipart mold with the an internal geometry appropriate for a particular nozzle configuration. The use of mold-free rapid prototyping methods for fabricating WC preforms would allow for rapid variations in preform geometries that, in turn, could be rapidly converted into dense, near net-shape/net-dimension ZrC/W-based composites for subsequent component testing (e.g., rocket tests of nozzle and nozzle liners with varied configurations).…”