Room Temperature Brittlement of T2 in the Mo-Si-B System
Compression and three-point bending tests were conducted at room temperature (RM) on the Mo5SiB2 (T2) alloy,which was prepared by sparking plasma sintering (SPS).It was found that almost no plastic deformation occured in the T2 alloy before failure but with a tremendous compressive strength of 2907 MPa.The fracture toughness determined from the single edge notch bend specimen is 3.34 MPa·m1/2,similar to the value of 3.5 MPa·m1/2 in ɑ-Al2O3.Once the cleavage crack initiated near the notch under continuous loads,it propagated on a certain plane (001) until the specimen completely fractured.In this work,the electronic structure was also calculated by the first-principles method,indicating that the contribution to RM brittleness is mainly caused by the covalent bonds which arrange alternately in the T2 phase.
T2 Intrinsic brittlement First-principles calculation Covalent bond
Kunming Pan Laiqi Zhang Wei Du Junpin Lin
State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, 100083, China
国际会议
the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))
太原
英文
132-138
2012-07-13(万方平台首次上网日期,不代表论文的发表时间)