The process and application analysis of the deposition of TiAl functionally graded material by co-sputtering

• Main Authors: Wen-Te Liao, 廖文德
• Other Authors: Shun-Fa Hwang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/17066800180958469390

碩士 === 國立雲林科技大學 === 機械工程系碩士班 === 93 === The research is to co-sputter Ti and Al with different deposition rate into a single layer and a multi-layer functional graded material (FGM) by using a PVD-DC/RF magnetron co-sputtering machine. This FGM is intended to be between a Ti layer and an Al layer. EDS, XRD, FESEM, TEM, α-Step, Nanoindenter and AES are used to analyze the composition, microstructure, surface roughness, thickness, hardness, and elastic modulus of the single layer and multi-layer FGM. The single layer FGM reveals that its composition as desired could be co-sputtered by controlling the power. The hardness and the elastic modulus of the single layer is increased by the increasing of Ti content. The multi-layer FGM is analyzed by TEM and AES, and the result illustrates that the composition of multi-layer could be continuously changed. From the analysis of thin film stress, the thermal stress will be less and even flatten out by increasing the gradient layer. To do the finite element analysis by ANSYS, the rule of mixture is used to describe the property of the FGM layer such that its mechanical properties are gradually changed along the thickness direction. Due to symmetry, only half of the specimen is analyzed and the thermal stress is calculated. The results show that the thermal stress of that with six-layer FGM is just 6% of that of the one with two-layer FGM. It is obvious that FGM can reduce the thermal stress effectively.