| 1 | TENSILE CREEP DEFORMATION AND DAMAGE BEHAVIOR IN A NICKEL-BASE SUPERALLOY AT 900℃显示文摘The tensile creep deformation and damage evolution in a Ni-base superalloy at 900℃/170MPa were investigated. At the first creep stage, abnormal creep occured due to the resolution of fine particles, and the deformation initiated from grain boundary areas. It is evident that nearly all of the dislocations were in γ matrix channels in form of dislocation pairs and the dislocations were impeded at γ/γ′ interfaces, thus the dislocation networks developed deformation. At the steady creep stage, impeded dislocations at γ /γ′ interfaces climbed over γ′ phases by diffusion-dominant mechanism.At the last creep stage, voids were formed around carbides at grain boundary which leaded to accumulated damage and caused creep rate accelerated. With the dislocation networks being broken, the voids connected and grew into micro-cracks gradually.Finally the cracks propagated along grain boundary area and resulted in failure. | H.C.Yu S.S.Xie H.C.Yang | 2004 | Acta Metallurgica Sinica(English Letters)2004，17，4： | 1 |
| 2 | SILICON MICRO-TRENCH ETCHING USING HIGH-DENSITY PLASMA ETCHER显示文摘Dry etching of silicon is an essential process step for the fabrication of Micro electromechancal system (MEMS). The AZ7220 positive photo-resist was used as the etching mask and silicon micro-trenches were fabricated with a multiplexed indu ctively coupled plasma (ICP) etcher. The influence of resist pattern profile, an d etch condition on sidewall roughness were investigated detail. The results sho w that the sidewall roughness of micro-trench depends on profiles of photo-resis t pattern, the initial interface between the resist bottom surface and silicon s urface heavily. The relationship between roughness and process optimization para meters are presented in the paper. The roughness of the sidewall has been decrea sed to a 20-50nm with this experiment. | T.T.Sun Z.G.Liu H.C.Yu M.B.Chen J.M.Miao | 2005 | Acta Metallurgica Sinica(English Letters)2005，18，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员