Abstract
β‐Si3N4 powder containing 1 mol% of equimolar Y2O3–Nd2O3 was gas‐pressure sintered at 2000°C for 2 h (SN2), 4 h (SN4), and 8 h (SN8) in 30‐MPa nitrogen gas. These materials had a microstructure of “in‐situ composites” as a result of exaggerated grain growth of some β Si3N4 grains during firing. Growth of elongated grains was controlled by the sintering time, so that the desired microstructures were obtained. SN2 had a Weibull modulus as high as 53 because of the uniform size and spatial distribution of its large grains. SN4 had a fracture toughness of 10.3 MPa‐m1/2 because of toughening provided by the bridging of elongated grains, whereas SN8 showed a lower fracture toughness, possibly caused by extensive microcracking resulting from excessively large grains. Gas‐pressure sintering of β‐Si3N4 powder was shown to be effective in fostering selective grain growth for obtaining the desired composite microstructure.
Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
