一种多晶石墨的拉伸蠕变行为

 对一种多晶石墨材料进行了拉伸蠕变试验后,用ＲＡＭＡＮＯＲＵ１０００拉曼光谱仪对蠕变前后的试样作了分析,并用扫描电镜观察了蠕变前后试样纵向剖面的孔隙变化。结果表明：在１７００℃,０．７ＭＰａ的应力作用下多晶石墨材料不发生明显蠕变。蠕变初期可用ε－ε０＝Ａｔｎ进行描述,在不同温度和应力下ｎ值从０．４８５～０．８之间变化。在同一应力条件下,随温度提高,ｎ值增大。激光拉曼光谱仪和扫描电镜分析表明,多晶石墨蠕变后石墨化程度增加、孔隙增多、变大。

THE TENSILE CREEP BEHAVIOR OF A POLYCRYSTALLINE GRAPHITE MATERIAL

The tensile creep was investigated on a polycrystalline graphite material.A specimen before and after creep was analyzed by RAM ANOR U1000 Raman Spectrum,and the varia- tion of pores on longitudinal profile by SEM observed.The results indicate that for a polycrystalline material creep does not take place obviously at 1700℃ and 0.7MPa stress.On ini- tial creep step,the relations can be expressed as ε-ε0=Atn. Under the conditions of different temperatures and stresses,the exponent n varies from 0.485 to 0.8.Under the same stress,n increases as the temperature is raised,The Raman spectrum analysis and SEM analysis show that after the polycrystalline graphite creeped, graphitization degree is increased and pores are multiplied and enlarged.