Abstract
In this study, a high-density ZrN/ZrSi2 composite reinforced with ZrO2 as an inert phase was synthesized under vacuum starting with a Zr-Si4N3-ZrO2 blend using combustion-synthesis methodology accompanied by compaction. The effects of ZrO2 additions (10–30 wt%) and compression loads (117–327 MPa) on the microstructure, porosity and hardness of the samples were studied. The process was monitored using XRD, SEM, EDS, porosity, density and hardness measurements. Thermodynamic calculations of the effect of ZrO2 addition on the combustion reaction were performed including the calculation of the adiabatic temperatures and the estimation of the fractions of the liquid phase. The addition of up to 20 wt% ZrO2 improved the hardness and reduced the porosity of the samples. Using 20 wt% ZrO2, the sample porosity was reduced to 1.66 vol%, and the sample hardness was improved to 1165 ± 40.5 HV at 234 MPa.
Highlights
The transition metal nitrides group is related to a family of materials featuring a combination of exceptional characteristics, such as a high melting point, very high hardness, metallic luster, and sometimes shining colors
Owing to its unique physical and chemical properties, zirconium nitride ZrN is considered an important candidate of the nitrides group
To the best of our knowledge, no available studies reported the fabrication of ZrN/ZrSi2 /ZrO2 composites by combustion synthesis
Summary
The transition metal nitrides group is related to a family of materials featuring a combination of exceptional characteristics, such as a high melting point, very high hardness, metallic luster, and sometimes shining colors. Their simple metallic structures are usually associated with outstanding thermal and electrical conductivities [1]. SiC/ZrSi2 mixtures have been reported to be suitable sintering aids for ZrB2 ceramics because they enhance their sintering and mechanical properties [26,31,32]. High-density monolithic ZrN has been fabricated without sintering aids via spark plasma sintering using commercially available ZrN powder [33]. To the best of our knowledge, no available studies reported the fabrication of ZrN/ZrSi2 /ZrO2 composites by combustion synthesis
Sign-in/Register to view highlights & summary 
Published Version (
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