| Phosphate composites have excellent properties in high temper ature and dielectric properties,so they are widely used in the fiel d of next-generation spacecraft. The stability of mullite is very g ood, and its physicochemical property matches Aluminum-Chromiu m-Phosphate. Mullite whisker usually as Reinforcing material is u sed in high temperature structural materials. In the thesis, the eff ect on sample performance of various factors in sintering process is systematically studied so that mullite whisker can better used t o strengthen the performance of Aluminum-Chromium-Phosphate.In the thesis, I have studied the effects of various factors on mullite whisker strengthening the performance of Aluminum-Chro mium-Phosphate. These factors include following aspects: ball-mill ing time, briquetting pressure, sintering temperature, sintering time, heating rate. When ball-milling time is 24 hours, particle size of milled material is smallest, and is easy to access to quality sam ples by following procedure. I studied the effect on sample perfor mance of percentage composition of Al F3. When the percentage co mposition of Al F3 is 5%, both can provide moderate gas phase at mosphere for mullite whisker formation, and can ensure density of sample. I studied the molding pressure of ceramic body, and find out that the appropriate pressure is 30 MPa. Near by 30 MPa, diel ectric constant increases accompany pressure increasing, mechanica l properties enhance accompany pressure increasing.. I studied ef fect on sample performance of sintering temperature、 sintering tim e、 heating rate. And I sought out good parameters and temperatu re curve with 1500 ℃and 4 hours.The main analysis and test methods: XRD, SEM, dielectric co nstant, linear shrinkage, Vickers hardness. In the thesis, I ascertai n some parameters of sintering, summarized the effects law of var ious factors, have accumulated a large of data. |
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