放电等离子烧结和快速热压工艺制备具有低或负热 膨胀系数钨酸锆块体(英文)

采用快速热压工艺(放电等离子烧结和感应加热热压),利用ZrW2O5粉料制备了负热膨胀系数(coefficient of thermal expansion,CTE)钨酸锆 (ZrW2O8)陶瓷体材料.这两种工艺可在烧结过程中保留负CTE材料钨酸锆所需的结构和相组成.结果表明:改变工岂参数,如热压温度和保温时间, 可以调节ZrW2O8陶瓷的CTE从-9×10-6/K到+9×10-6/K变化.首次采用ZrW2O8作为填料与轻金属钛复合制备了零膨胀复合材料.

BULK ZIRCONIUM TUNGSTATE WITH A LOW OR NEGATIVE COEFFICIENT OF THERMAL EXPANSION PREPARED BY SPARK PLASMA SINTERING AND RAPID HOT PRESSING PROCESSES

Zirconium tungstate (ZrW2O8) ceramic materials with a negative coefficient of thermal expansion (CTE) were prepared by rapid hot pressing techniques (spark plasma sintering, inductively heated hot pressing) using ZrW2O8 powder. The processes allow preserving the required stucture and phase composition of the negative CTE ZrW2O8 ceramics. It shows that the variation of the process parameters (hot pressing temperature, Keeping time) allows a certain tailoring of the CTE in a range from -9 ×10-6/K to +9 × 10-6/K. A first attempt was made to use the negative CTE ZrW2O8 filler powder in a light mass matrix (titanium) to obtain a zero CTE composite with metallic matrix.