Erosive Simulation Analysis And Preparation Of Laminated Composite Pipe With Wear-resistant And Anti-corrosive Properties

The dissertation could be divided into two sections. The first section is mainly about the preparation, characterization and finite element (FE) analysis of the wear-resistant laminated composite pipe. The centrifugal-SHS process to prepare ceramic-lined composite pipe was introduced. The phase compositions and physical properties for the raw materials powders and the products have been characterized. The FE method has been adapted to simulate the residual thermal stresses in composite pipes. The ternary composite pipes were prepared by reactive impregnating blended resin onto the internal surface of ceramic-lined pipes. The interfacial stresses of the ternary composite pipe in service have been investigated through FE analysis. Furthermore, the erosion testing machine has been designed to test the erosion performance of two composite pipes. The second section of the dissertation is about the mechanism of the erosive wear and the erosion models. The impact factors of erosive wear on the materials and products have been discussed in details. The erosion mechanisms of ductile materials and brittle materials have been emphatically analyzed. And the application prospects for numerical simulation analysis techniques in the field of material wear were given as well. A brand new universal FE model of erosive wear was built. Utilizing the FE model, two examples of ductile materials and brittle materials were employed to simulate the effect of the impact angle, impact velocity and particles penetration on the targets. Moreover, a coupled model of erosive wear with meshfree simulation technique and FE method was established, which was the first time to use meshfree simulation technique in studying a wear process. The detailed research contents and results are summarized as follows:1. The preparation of the wear-resistant ceramic-lined composite pipeThe jig-type SHS-centrifugal machine has been designed using centrifugal-SHS process, with which the metallurgical bonding ceramic-lined has been successfully sintered into the internal surface of the steel pipe. The powders of raw materials and the products of ceramics-lined layer have been systemically characterized by DSC, XRD, EDS, SEM and TEM. The results display that the ceramic-lined pipe has outstanding erosion resistance and good thermal fatigue resistance and high surface hardness. It could be widely used in many fields such as electricity, petrochemical industry, metallurgy, chemical industries, etc.2. FE analysis of residual thermal stress in ceramic-lined composite pipeThe temperature distribution and transformation during the cooling process of the ceramic-lined composite pipe preparation were emphatically analyzed with FE method. With the function of transient thermal analysis and thermal-structure coupling of ANSYS, the residual thermal stress of the composite pipe was numerically simulated. The effect of the thickness of SHS-layer on the performance of the ceramic-lined composite pipe was investigated as well. The results of numerical analysis indicate that reasonable adjustment of the thickness of SHS-layer could reduce the interfacial stress between any two layers so that the service life, safety and reliability of the ceramic-lined composite pipe would be improved.3. The preparation of the ternary composite pipe and the effect of different component materials on pipeA kind of anti-corrosion ternary composite pipe was developed by reactive impregnating blended resin onto the internal surface of the ceramic-lined pipe. The ternary composite pipe could be used in the working conduction with the interaction of corrosion and wear. Utilized FE method, the characteristic for the interfaces of the composite pipe was numerically modeled and the effect of variation of their physical parameter on the mechanical property of the composite piping was analyzed as well. The numerical analysis results show that the reasonable adjustment of Young's modulus and Poisson's ratio of ceramic intermediate layer formed in the ternary composite pipe could reduce the interfacial stress between layers so that the service life and safety reliability of the pipe would be enhanced.4. The erosion test for the laminated composite pipeFor a common failure mode of erosive wear under pipe service conditions, according to the relevant standards, the erosion testing machine has been designed and manufactured. The erosion performances for the internal layer materials of the laminated composite pipe, Al₂O₃ ceramics of ceramic-lined pipe and blended resin sample of the ternary pipe, were examined on the erosion testing machine. The results indicate that the two linings show typical brittle erosive behavior, which has most serious damage at 90°impact angle. The blended resin which filled with modified nano-particles Al₂O₃ demonstrated excellent erosive wear resistance properties5. The impact factors of erosive wear and the erosion mechanism study.The materials erosive behavior was further studied from the impact factors of erosion. The effects of impact angle, erodent velocity and erodent particle size on weight loss of target materials were focused. The erosion failure mechanisms were particularly distinguished from ductile mode to brittle mode. At the same time, the application prospects for numerical simulation in the field of material wear failure were explained.6. FE model of erosive wear on ductile and brittle materialsA brand new universal FE model of erosive wear was established. The Johnson-Cook and Johnson-Holmquist materials model and the corresponding equation of state used in the FE model were described in more details. Utilizing the FE model, two examples of ductile materials and brittle materials were employed to simulate the effect of the impact angle, erodent velocity and particle size as well as particle penetration on the targets. The energy transfer and surface residual were calculated as well. It is shown that the predicted results are in agreement with published results obtained experimentally and from analytical erosion models. The present study could be useful and efficient in studying erosive wear.7. Coupled FE and meshfree model for erosive wearA coupled finite element and meshfree model was established for the simulation and prediction of erosive wear. The error due to mesh distortion and tangling at impacted area in the FE analysis could be avoided utilizing the meshfree technique. The computer simulations of high velocity erosive wear on a ductile target Ti-6Al-4V against steel particles' impacting and on an aluminum substrate with organic coating have been performed. The fundamental mechanisms of erosion by solid particle impact and the coating debonding behavior were investigated through the coupled numerical model. The coupled model has instructive significance for researching the mechanisms of high velocity erosive wear and the coating debonding mechanisms.