Research On The Properties And Key Technology Of Rapid Prototyping Pieces With WPC

The Selective Laser Sintering is based on the principle of laminated manufacturing and superposition and also take advantage of CAD&CAM technology to make solid powder into three-dimensional parts. Using polymers and compound powder to make functional components is one of the typical directions of SLS development and has promising prospects on application. Although domestic and international researchers have studied on this technology in depth, there are still considerable critical technical problems need to be solved. So to speak, research on the critical issue of SLS on wood-plastic composite materials is promising.This article gives a brief introduction for the definition of rapid prototype and background for generation, present situation of research both in domestically and foreign country and developing trends, especially have a discussion and analysis on SLS technology's present situation of research both in domestically and foreign country, principles of working and characteristics of process, what's more, based on the former research, it demonstrates the purpose and significance of this issue. The purpose of the article is mainly on solving the problems of properties and critical technology of rapid prototype components based on wood powder to reach the objective of reducing cost and enlarge the area of application of rapid prototype material.This article refers to the present achievement of interface-compatible and interface-sintering principles and carefully analyzes the properties of wood powder, PES and PP, mainly researching on the compatibility after mixture and it's sintering principle, and base on this, I conducted the making of mixed powder and its process.Through test and analysis, the compatibility of interface between wood-plastic has been improved. According to the research, there are two methods with which we can improve the compatibility. One method is that we can process the surface of wood fibers by alkalization to reduce the repulsion with hydrobolicity, meanwhile, the interfacial compatiblizer should be used. Through test and SEM analysis, we conclude that the force such as van force, electrostatic force and capillary force and so forth make material contact efficiently while sintering, meanwhile it attains sintering neck and molecule segment, and it's internal rotation is the main mechanism of material migration of polymers sintering. Molecule segment's flexibility increases and it's strength decreases with the increasing of temperature.This article has a specific analysis on the temperature field of wood-plastic powder bed, thermal stress and strain field in the process of SLS, and discusses heat transmission and distribution from the perspective of power density. The article talks about the precision problem of formed parts in SLS systematically though test and theory, and discusses all composing parts of precision, its forming reason and its effects respectively, which makes me draw the following conclusions that the errors of formed components consists of the error of machine's system, CAD mold, process, secondary sintering and surplus within Z axis. It points out that the main shape error of formed components is mainly due to forming warp age which is caused by the inconsistency of contract among layers, and we can divide one-dimensional warpage and two-dimensional warpage.To sintering the compound material and finally manages to make the test components,then did some mechanics property test,analysis with SEM,as well as sintering process parameter optimization, the tests shows that with the change of wood-plastic powder and MAH, the wood-plastic powder's stretching, bending and impact strength are changed. Compatibilizer is good for the improvement of mechanics property of compound materials. The using of optimized sintering parameter can bring us high density test parts whose mechanics property has been improved greatly at the same time.This research promotes the development of domestic polymers and its compound powder used in SLS and fills in the blank of application of wood-plastics material in laser sintering, and does well for boosting the progressing of domestic SLS technology, and also has significance in improving the using of SLS technology in all professions.