Exploration Into The Mechanical Properties Of Test Samples Prepared By A Novel Hot Pressing Method

This paper is mainly to explore into high quality of test samples prepared by a novel hot pressing method.The thesis is mainly focused on two aspects as follows:Firstly,PP material was used,to compare the characteristics of two methods of sample preparation:molding method and molding-cut method,and then the best hot pressing conditions was explored.The comparison of the two methods was done by testing the mechanical properties of samples prepared.Dumbbell samples of PP of different temperature,pressure and hot press time were prepared by the two methods and used for the tensile test.By changing the temperature and holding other conditions constant,the best processing temperature was determined through the observation of tensile test data and the surface of the sheets.Similarly,the best hot press pressure and time were confirmed.Analysis showed that the molding-cut method was better than the molding method.Although the processes involved in molding-cut method were complicated and more materials were needed for sample preparation,the sheet was uniform and had good performance.Besides,the optimal processing conditions were 210?,40MPa and 5 min for temperature,pressure and time respectively.Secondly,an exploration into high quality samples of epoxy resin by hot pressing method was carried out and its advantages and disadvantages was compared with that of the conventional casting method.Exploration into high quality epoxy resin samples prepared by a novel hot pressing method.There were two problems to be overcome in making a good sample of epoxy resin.The first one was how to eliminate bubbles from samples and the second one was how to remove the samples from the mold.We groped for two methods to get rid of the bubbles.The first one was to drop bubbles off before the epoxy resin AB glue mix.Another one was to drop bubble off after the epoxy resin AB glue have mixed.Analysis showed that it would be better to get rid of the bubbles before the epoxy resin mixes.The best pressure,the temperature and time for making an epoxy resin sample using hot pressing method were then determined.Analysis also showed that the optimal processing conditions for the samples were 100?,30-40 MPa and 10 min for temperature,pressure and time respectively.To solve the problem on how to remove samples from the mold perfectly,the mold was heated and the best temperature was found to be 80?.Also,the mechanical properties of the samples made by hot pressing method were compared with conventional casting method.Lastly,the merits and demerits of the two methods have been given.