离心喷射沉积Ti-48Al-2Mn-2Nb的疲劳裂纹扩展速率和门槛值  

FATIGUE CRACK GROWTH RATES AND FATIGUE THRESHOLDS OF CENTRIFUGAL SPRAY DEPOSITED Ti-48Al-2Mn-2Nb

作　　者：陈文哲[1] 张飒 钱匡武[1] 顾海澄[2] 王中光[3] 

机构地区：[1]福州大学材料系,福州350002 [2]西安交通大学材料学院,西安710049 [3]中国科学院金属研究所材料疲劳与断裂国家重点实验室,沈阳110015

出　　处：《金属学报》1998年第1期70-74,共5页Acta Metallurgica Sinica

基　　金：福建省自然科学基金!E95002

摘　　要：本文着重研究了采用特殊的离心喷射沉积成型方法制备的Ti-48Al-2Mn-2Nb金属间化台物的室温疲劳裂纹扩展速率和疲劳门槛值.试验采用三点弯曲单边切口试样进行恒载和逐级降载控制的压-压疲劳试验,结果表明．具有层片状组织的离心喷射成型（CSD）样品比经热等静压（HIP）后具有双态组织样品表现出更高的疲劳裂纹扩展阻力和疲劳门槛值，其Paris经验式分别为da／dN＝3．8×10-12（△K）6和da／dN＝1．9×10-17（△K）12；而CSD和HIP试样的疲劳门槛值分别为10．5MPa.m1／2和7.The fatigue crack growth rates and fatigue thresholds of a Ti-48Al-2Mn-2Nb intermetallics, which was formed by a special spray forming technique so--called' centrifugal spray deposition' (CSD) under a low vaccum condition, were investigated at ambient temperature.Threepoint bend fatigue specimens with notch length of 0.5 mm were prepared and compressioncompression fatigue tests were carried out under load control. The results show that CSD samples with lamellar-structure have a better fatigue crack growth resistance and a higher fatigue threshold than that of HIP (hot isostatic pressing) samples with duplex structure. The relationship of da/dNversus △K could be shown as: da/dN=3.8×10-12 (△K)6 for CSD samples and da/dN=1.9 ×10-17 (△H)12 for HIP samples, and the fatigue thresholds of CSD and HIP samples are 10.5 MPa m1/2 and 7.5 MPam1/2, respectively.

关 键 词：离心喷射沉积 裂纹扩展速率 门槛值 钛铝合金 

分 类 号：TG111.8[金属学及工艺—物理冶金] TG146.23[金属学及工艺—金属学]