Thermal expansion behaviour of barium and strontium zirconium phosphates

Bulletin of materials science

A M Umarji¹  Sheela K Ramasesha²  P Srikari Tantri²  K Geetha¹ 

[1] Materials Research Centre, Indian Institute of Science, Bangalore 560 012, India$$Materials Research Centre, Indian Institute of Science, Bangalore 560 012, IndiaMaterials Research Centre, Indian Institute of Science, Bangalore 560 012, India$$;Materials Science Division, National Aerospace Laboratories, Bangalore 560 017, India$$Materials Science Division, National Aerospace Laboratories, Bangalore 560 017, IndiaMaterials Science Division, National Aerospace Laboratories, Bangalore 560 017, India$$

关键词: Coefficient of thermal expansion;    low thermal expansion;    NZP;    ceramic;    dilatometer;    anisotropy.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Ba_{compounds with0, 0.25, 0.5, 0.75, 1.0, 1.25 and 1.5, belonging to the low thermal expansion NZP family were synthesized by the solid state reaction method. The XRD pattern could be completely indexed with respect tospace group indicating the ordering of vacancy at the divalent cation octahedral sites. The microstructure and bulk thermal expansion coefficient from room temperature to 800°C of the sintered samples have been studied. All the samples show very low coefficient of thermal expansion (CTE), with samples showing negative expansion. A small substitution of strontium in the pure barium compound changes the sign of CTE. Similarly,sample (pure strontium) shows a positive CTE and a small substitution of barium changes its sign. samples have almost constant CTE over the entire temperature range. The low thermal expansion of these samples can be attributed to the ordering of the ions in the crystal structure of these materials.}

【 授权许可】

Unknown