A contribution of X ray diffraction analysis in the determination of creep of Si3N4 ceramics

Autor(es)

Claudinei dos Santos ^[1] ; Kurt Strecker ^[2] ; Francisco Piorino Neto ^[3] ; Olivério Moreira Macedo Silva ^[4] ; Cosme Roberto Moreira da Silva ^[5]

Afiliação do(s) autor(es)

^[1] Faculdade de Engenharia Química de Lorena. Departamento de Engenharia de Materiais - Brasil

^[2] Faculdade de Engenharia Química de Lorena. Departamento de Engenharia de Materiais - Brasil

^[3] Centro Técnico Aeroespacial. Divisão de Materiais - Brasil

^[4] Centro Técnico Aeroespacial. Divisão de Materiais - Brasil

^[5] Centro Técnico Aeroespacial. Divisão de Materiais - Brasil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 9, n. 1, p. 1-8, 2006-03-00.

Resumo

The understanding of the creep behavior of silicon nitride (Si3N4) is extremely complex because of a large number of parameters influencing simultaneously the creep deformation of the materials. In general, the main creep mechanisms acting in these materials are grain boundary sliding or materials transport by solution-precipitation process. In this work, the creep behavior has been monitored by X ray diffraction analysis, determining the peak intensity ratio of the (101) and (210) planes of b-Si3N4. This characterization technical, allied the microstructural analysis can contribute to determination of creep mechanisms acting in material. The beta-Si3N4 grains are highly elongated with aspect ratios ranging between 3 and 11. Therefore, the intensity of the peaks related to the basal plane (101) tends to be higher when compared to the lateral planes (210). During creep deformation occurs alignment of the elongated beta-Si3N4 grains in the plane parallel to the direction of the applied load, reflecting in the peak intensity ratio. Crept samples presented variations in the (101)/(210) peak intensity ratio of beta-Si3N4 indicating that grain rotation can to be contributing with creep deformation. In this way, the use of X ray diffractometry as a mean to characterize microstructural changes during creep has been shown successfully. (AU)

• Processo FAPESP: 01/08682-6 - Estudo dos mecanismos de fluência do Si3N4 prensado a quente, aditivado com CTR2O3/AIN e CTR2O3/AI2O3
• Beneficiário: Claudinei dos Santos
• Modalidade de apoio: Bolsas no Brasil - Doutorado