Papers by Author: Xiang He Peng

Abstract: As a new intelligent material, Nano-Magnetorheological Material (Nano-MRM) gets a wide range of great concern to researchers and its application scope is very broad. For diagnosis and treatment cancer in one of the most difficult types of intracranial aneurysm, the work established the most practical model on Nano-MRM in intracranial aneurysm therapy research and analyzed quantitatively. The results are effective. Hope the work can be a strong impetus to human progress in the anti-cancer project.

Abstract: The kind double-channel Magnetorheological Fluids (MRFs) testing equipment is characterized by low inertia of rotating element and ensures certain precision and economical applicability. Especially, research on and analyze the strain tensor by Finite element software Abaqus. Hope cordially the research can accelerate the study of MRFs with a rapid development.

Abstract: An incremental form of constitutive model is proposed for shape memory alloys using the modified strain based on experimental results and the finite element analysis, taking into account of the laminar microstructure, the thickness of martensite phase lamina and the interaction between the two phases. The pseudoelastisity of NiTi shape memory alloy micro-tube subjected to pure tension and pure torsion are analyzed and compared with the experimental results respectively. It can be seen that the pseudoelastic behavior, especially the stress drop during tension processes, can be well described with the proposed model.

Abstract: A two-phase constitutive model for shape memory alloys (SMAs) is proposed based on the fact that SMAs is dynamically composed of austenite and martensite. The behavior of SMAs is regarded as the dynamic combination of the individual behavior of each phase. This model can describe the main characteristics of SMAs, such as pseudoelasticity and shape memory effect. The corresponding numerical algorithm was also developed to describe the main features of shape memory alloy Au-47.5at.%Cd.

Abstract: The microstructure and mechanical properties of magnetorheological (MR) fluids with mixed particles of different size are investigated. The interaction between particles of different radius is obtained and the model for motion of particles is proposed. Under an external magnetic field, the microstructure and yield shear stress of MR fluids with mixed particles of different sizes are simulated. It shows that particle size ratio in bidisperse suspensions can influence the performance of MR fluids.

Abstract: Scanning electron microscope (SEM) observation was performed and showed that shank bone is a kind of bioceramic composite consisting of laminated hydroxyapatite and organic materials. The hydroxyapatite layers are parallel with the surface of the bone and consist of numerous thin and long hydroxyapatite sheet fibers. The hydroxyapatite sheet fibers in different hydroxyapatite make a little angle with each other and compose a kind of screwy microstructure. The maximum pullout force of the screwy microstructure was investigated and compared with that of parallel microstructure. It shows that the maximum pullout force of the screwy microstructure is markedly larger than that of the parallel microstructure, which was experimentally validated.

Abstract: As a typical biological material, bone possesses high fracture strength and fracture toughness, which are closely related to its exquisite microstructure. SEM observation of a cannon bone shows that the bone is a kind of layered bioceramic composite consisting of hydroxyapatite sheets and collagen matrix. The hydroxyapatite sheets are of long and thin shape, distributing in parallel. The fracture toughness of the bone is analyzed with the representative model of the hydroxyapatite sheets and the concept of maximum pullout energy. It is shown that the lathy shape as well as the parallel distribution of the hydroxyapatite sheets increases the pullout energy and endows the bone with high fracture toughness.

Abstract: Scanning electron microscope (SEM) observation shows that Solid-trough shell is a kind of bioceramic composite consisting of laminated aragonite and organic materials. The aragonite layers are parallel with the surface of the shell and consist of numerous thin and long aragonite fibers. The aragonite fibers in an arbitrary aragonite layers possess different directions and compose a kind of screwy microstructure. The maximum pullout force of the screwy microstructure was investigated and compared with that of parallel microstructure based on their representative models. It shows that the maximum pullout force of the screwy microstructure is markedly larger than that of the parallel microstructure, which was experimentally validated.

Abstract: Bone is a kind of biomaterial in nature. It behaves favorable strength, stiffness and fracture toughness which are closely related to its fine microstructures. Scanning electron microscope (SEM) observation on a shinbone shows that the bone is a kind of natural bioceramic composite consisting of hydroxyapatite layers and collagen matrix. The hydroxyapatite layers are arranged in a parallel distribution and consist of many hydroxyapatite sheets. The fracture toughness of the bone was analyzed based on the representative model of the microstructure in the bone and the idea of maximum pullout energy. The analytical result shows that the long and thin shape as well as the parallel distribution of the hydroxyapatite sheets increase the maximum pullout energy of the sheets and enhance the fracture toughness of the bone.

Abstract: Bone possesses excellent mechanical properties, which are closely related to its favorable microstructures optimized by nature through many centuries. In this work, a scanning electron microscope (SEM) was used to observe the microstructures of a cannon bone. It showed that the bone is a kind of bioceramic composite consisting of hydroxyapatite layers and collagen protein matrix. The hydroxyapatite layers are composed of long and thin hydroxyapatite sheets. The hydroxyapatite sheets in different hydroxyapatite layers distribute along different orientations, which composes a kind of cross microstructure. The maximum pullout force of the cross microstructure was investigated and compared with that of the 0° microstructure with their representative models. The result indicated that the maximum pullout force of the cross microstructure is markedly larger than that of the 0° microstructure.