压痕法测定Mo_5SiB_2合金断裂韧性的经验方程确定  

Determination of empirical equation of fracture toughness for Mo_5SiB_2 alloy by indentation method

作　　者：张来启[1] 黄永安[1] 黄蕾[1] 林均品[1] 

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《材料热处理学报》2017年第1期178-183,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金项目(50871012)

摘　　要：分析了载荷对Mo_5SiB_2合金压痕裂纹影响规律,观察了压痕裂纹形貌特征,表征了裂纹长度与载荷的关系,确定了压痕裂纹系统,选取不同的压痕方程计算了室温断裂韧性KIC值,探讨了压痕载荷以及压痕方程对KIC值的影响关系。结果表明,Mo_5SiB_2合金压痕裂纹系统属于中位裂纹,只要选择合适的压痕方程,载荷并不影响断裂韧性值。压痕法测定Mo_5SiB_2合金断裂韧性合适的经验方程为KIC=0.8193H^(0.5)E^(0.5)a^2c^(-1.5),测得的其KIC值为2.63 MPa·m^(1/2)。The influence of load for indentation crack of Mo_5SiB_2alloy was analyzed,the morphology characteristics of indentation crack was observed,the relationship between crack length and load was characterized.Then the indentation crack system was determined,and different indentation equations were selected to calculate the fracture toughness KICvalue of the alloy at room temperature.The relationship of indentation load and indentation equations on KICvalue was discussed.The results show that indentation crack of the Mo_5SiB_2alloy is in line with the median crack under this experimental conditions,the load does not affect fracture toughness as long as the appropriate indentation equation is used.Empirical equation of M-3（ KIC= 0.8193H^（0.5）E^（0.5）a^2c^（-1.5）） is suitable for calculating KICvalue of the Mo_5SiB_2alloy and the value is 2.63 MPa·m^（1/2）.

关 键 词：Mo_5SiB_2 合金 压痕法 断裂韧性 经验方程 

分 类 号：TG115.5[金属学及工艺—物理冶金]