School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, No.2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu, Sichuan, China
Dr. Zhi Zeng
School of Mechanical and Electrical Engineering, University of Electronic Science and Technology of China, No.2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu, Sichuan, China
Compared to the common selective laser sintering (SLS) manufacturing method, fused deposition modeling (FDM) seems to be an economical and efficient three-dimensional (3D) printing method for high temperature polymer materials in medical applications. In this work, a customized FDM system was developed for polyether-ether-ketone (PEEK) materials printing. The effects of printing speed, layer thickness, printing temperature and filling ratio on tensile properties were analyzed by the orthogonal test of four factors and three levels. Optimal tensile properties of the PEEK specimens were observed at a printing speed of 60 mm/s, layer thickness of 0.2 mm, temperature of 370 °C and filling ratio of 40%. Furthermore, the impact and bending tests were conducted under optimized conditions and the results demonstrated that the printed PEEK specimens have appropriate mechanical properties.
6 January 2023 in International Journal of Heat and Mass Transfer
Ag nanoparticles (NPs) with about 40 nm diameter covered with 5–8 nm organic shell were prepared by chemical reduction reaction. The thermal characteristics of Ag nanoparticle (NP) paste were measured by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The low‐temperature sintering bonding processes using Ag NP paste were carried out at the temperature range of 150–350°C for 5 min under the pressure of 3 MPa. The microstructures of the sintered joint and the fracture morphology were evaluated by scanning electron microscopy (SEM). The shear strength was used to evaluate the mechanical property of the sintered joint. TGA‐DSC test showed that the Ag content is approximately 95.5 mass% in Ag NP paste. The average shear strength of the joint fabricated at 250°C for 5 min under the pressure of 3 MPa was about 28 MPa, which could meet the requirements of electronics packaging working at high temperature. The joint shear strength increased with the increase of the sintering temperature due to much denser sintered Ag NPs and more comprehensive metallurgical bonds formed in the joint.