Tensile creep of Mo-Si-B alloys

被引:96
作者
Jain, P. [1 ]
Kumar, K. S. [1 ]
机构
[1] Brown Univ, Div Engn, Providence, RI 02912 USA
关键词
Refractory metals; High temperature deformation; Dislocations; Segregation; Precipitation; METAL-MATRIX COMPOSITES; SOLID-SOLUTION ALLOY; POWER-LAW CREEP; MECHANICAL-PROPERTIES; ELEVATED-TEMPERATURES; INTERMETALLIC ALLOYS; DEFORMATION-BEHAVIOR; SINGLE-CRYSTALS; FLOW BEHAVIOR; T-2; PHASE;
D O I
10.1016/j.actamat.2009.11.054
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Multiphase Mo-Si-B alloys containing a Mo solid solution matrix and brittle Mo3Si and Mo5SiB2 (T2) intermetallic phases are candidates for ultra-high-temperature applications. The elevated temperature uniaxial tensile response at a nominal strain rate of 10(-4) s(-1) and the tensile creep response at constant load between 1000 degrees C and 1300 degrees C of a (i) single phase solid solution (Mo-3.0Si-1.3B in at.%), (ii) two-phase alloy containing similar to 35 vol.% T2 phase (Mo-6Si-8B in at.%) and (iii) three-phase alloy with similar to 50 vol.% T2 + Mo3Si phases (Mo-8.6Si-8.7B in at.%) were evaluated. The results confirm that Si in solid solution significantly enhances both the yield strength and the creep resistance of these materials. A Larson-Miller plot of the creep data showed improved creep resistance of the two- and three-phase alloys in comparison with Ni-based superalloys. The extent of Si dissolved in the solid solution phase varied in these three alloys and Si appeared to segregate to dislocations and grain boundaries. A stress exponent of similar to 5 for the solid solution alloy and similar to 7 at 1200 degrees C for the two multiphase alloys suggested dislocation climb to be the controlling mechanism. Grain boundary precipitation of the T2 phase during creep deformation was observed and the precipitation kinetics appear to be affected by the test temperature and applied stress. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:2124 / 2142
页数:19
相关论文
共 41 条
[1]   Creep effects on crack growth in a Mo-Si-B alloy [J].
Alur, A. P. ;
Chollacoop, N. ;
Kumar, K. S. .
ACTA MATERIALIA, 2007, 55 (03) :961-974
[2]   High-temperature compression behavior of Mo-Si-B alloys [J].
Alur, AP ;
Chollacoop, N ;
Kumar, KS .
ACTA MATERIALIA, 2004, 52 (19) :5571-5587
[3]   Ultrahigh-temperature Nb-silicide-based composites [J].
Bewlay, BP ;
Jackson, MR ;
Zhao, JC ;
Subramanian, PR ;
Mendiratta, MG ;
Lewandowski, JJ .
MRS BULLETIN, 2003, 28 (09) :646-653
[4]  
CARVALHINHOS H, 1967, J I MET, V95, P364
[5]   STEADY-STATE POWER-LAW CREEP IN HETEROGENEOUS ALLOYS WITH COARSE MICROSTRUCTURES [J].
CHEN, IW ;
ARGON, AS .
ACTA METALLURGICA, 1979, 27 (05) :785-791
[6]   On the fracture and fatigue properties of Mo-Mo3Si-Mo5SiB2 refractory intermetallic alloys at ambient to elevated temperatures (25 °C to 1300 °C) [J].
Choe, H ;
Schneibel, JH ;
Ritchie, RO .
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 2003, 34 (02) :225-239
[7]   Power-law creep of powder-metallurgy grade molybdenum sheet [J].
Ciulik, J. ;
Taleff, E. M. .
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 2007, 463 (1-2) :197-202
[8]   NIAL ALLOYS FOR HIGH-TEMPERATURE STRUCTURAL APPLICATIONS [J].
DAROLIA, R .
JOM-JOURNAL OF THE MINERALS METALS & MATERIALS SOCIETY, 1991, 43 (03) :44-49
[9]  
Davis L.E., 1976, HDB AUGER ELECT SPEC
[10]   Mo-Si-B alloys: Developing a revolutionary turbine-engine material [J].
Dimiduk, DM ;
Perepezko, JH .
MRS BULLETIN, 2003, 28 (09) :639-645