Papers by Author: Jiang Tao Li

Abstract: Dense Y³⁺-dopted α-SiAlON/BN composition ceramics was fabricated by hot pressing at 1900 °C for 60 min, and flextural strength at room and 1000 °C was investigated through three-point bending test. The results show that h-BN contribute to the densification of powder body, but h-BN have little affect on the key temperature region of sintering densification of α-SiAlON ceramics. When content of BN is lower, which didn’t affect on the phase transformation of α-SiAlON, but when content of BN is higher, besides of major phase α-SiAlON, a little of β-SiAlON was also formed. For the α-SiAlON/BN composite ceramics content of 20 wt.% h-BN, the higer flexural strength( room-temperature and 1000 °C) were abtained, the formation of β-SiAlON should be an important resonon for the higher strentgh, more important is , whose flexural strength at 1000 °C is higher 50 MPa than at room temperature, the differnce of thermal properties between SiAlON and BN should contribute to the improve of high-temperature flextural strength.

Abstract: The single-phase Y-α-sialon ceramics with highly optical transmittance were produced by hot pressing starting mixtures of Si₃N₄, AlN, Al₂O₃ and Y₂O₃ at 1900 °C for 0.5 h in a nitrogen atmosphere. The resultant sialon shows very high optical transparency in the near infrared wavelength region, about 70% for 0.8 mm thickness. In addition to highly transmittance, the Y-α-sialon also show high hardness (19 GPa) and well fracture toughness (4 MPa•m^1/2), which attribute to the compound microstructure of uniform, equiaxed grain with a grain size of 2 μm and small aspect ration elongated α-sialon (<2) with a length no more than 5 μm. The high transparent was attribute to the uniform dense microstructure and pure single-phase α-sialon.

Abstract: Every year, roughly two million patients worldwide sustain a bone grafting procedure to repair bone defects stemming from tumor, the wound, the infection, as well as other reasons [1, 2]. The bone transplantation is one of main methods to treat bone damages [3]. The gold standard is to use autologous bone or autograft [4]. However, both the need of the second surgery and morbidity at the extraction site [5-7] has been an incentive to search for alternative treatment. One of them is to form bone graft bone. Many materials have been widely chosen to form bone graft substitutes: metals, polymers, ceramics, dehydrate, and calcium phosphates [8-13]. Although these synthetic materials provide an immediate solution for many patients, their long-term performance is generally not satisfactory. This is often due to a mechanical property mismatch between the implant failure and tissue damage [14, 15]. The development of combined artificial bone with improved mechanical properties and enhanced biocompatibility calls for a biomimetic approach using natural bone as a guide.