scholarly journals Propagation of Short Fatigue Cracks in Notched Specimens of Intermetallic Compound TiAl.

1997 ◽  
Vol 46 (11) ◽  
pp. 1261-1267 ◽  
Author(s):  
Yoshiaki AKINIWA ◽  
Keisuke TANAKA ◽  
Hidehiko KIMURA ◽  
Makoto KOGOSHI
Keyword(s):  
Intermetallic Compound ◽  
Fatigue Cracks ◽  
Notched Specimens ◽  
Compound Tial

Atomic structure of interface of intermetallic compound TiAl and nitride Ti2AIN using HREM and image processing

1991 ◽  
Vol 49 ◽  
pp. 570-571
Author(s):  
E. Sukedai ◽  
H. Mabuchi ◽  
H. Hashimoto ◽  
Y. Nakayama
Keyword(s):  
Mechanical Properties ◽  
Image Processing ◽  
Composite Material ◽  
Intermetallic Compound ◽  
Side Surface ◽  
High Resolution Electron Microscopy ◽  
Hexagonal Structure ◽  
Second Phase ◽  
Resolution Electron ◽  
Compound Tial

In order to improve the mechanical properties of an intermetal1ic compound TiAl, a composite material of TiAl involving a second phase Ti2AIN was prepared by a new combustion reaction method. It is found that Ti2AIN (hexagonal structure) is a rod shape as shown in Fig.1 and its side surface is almost parallel to the basal plane, and this composite material has distinguished strength at elevated temperature and considerable toughness at room temperature comparing with TiAl single phase material. Since the property of the interface of composite materials has strong influences to their mechanical properties, the structure of the interface of intermetallic compound and nitride on the areas corresponding to 2, 3 and 4 as shown in Fig.1 was investigated using high resolution electron microscopy and image processing.

Characteristics of the nitrogen ion implanted intermetallic compound TiAl

1993 ◽  
Vol 80-81 ◽  
pp. 250-253 ◽  
Author(s):  
Wang Xi ◽  
Yang Yunjie ◽  
Liu Xianghuai ◽  
Zou Shichang ◽  
Shigeji Tanaguchi ◽  
...  
Keyword(s):  
Intermetallic Compound ◽  
Nitrogen Ion ◽  
Compound Tial ◽  
Ion Implanted

Fatigue-Life Prediction Method Based on Small-Crack Theory in an Engine Material

2011 ◽  
Vol 134 (3) ◽  
Author(s):  
James C. Newman ◽  
Balkrishna S. Annigeri
Keyword(s):  
Crack Closure ◽  
Test Data ◽  
High Cycle Fatigue ◽  
Fatigue Cracks ◽  
Loading Conditions ◽  
Cycle Fatigue ◽  
Constant Amplitude ◽  
Notched Specimens ◽  
Wide Range ◽  
Stress Ratios

Plasticity effects and crack-closure modeling of small fatigue cracks were used on a Ti-6Al-4V alloy to calculate fatigue lives under various constant-amplitude loading conditions (negative to positive stress ratios, R) on notched and un-notched specimens. Fatigue test data came from a high-cycle-fatigue study by the U.S. Air Force and a metallic materials properties handbook. A crack-closure model with a cyclic-plastic-zone-corrected effective stress-intensity factor range and equivalent-initial-flaw-sizes (EIFS) were used to calculate fatigue lives using only crack-growth-rate data. For un-notched specimens, EIFS values were 25-μm; while for notched specimens, the EIFS values ranged from 6 to 12 μm for positive stress ratios and 25-μm for R = −1 loading. Calculated fatigue lives under a wide-range of constant-amplitude loading conditions agreed fairly well with the test data from low- to high-cycle fatigue conditions.

Fatigue Life Predictions of Smooth and Notched Specimens Based on Fracture Mechanics

1981 ◽  
Vol 103 (2) ◽  
pp. 91-96 ◽  
Author(s):  
M. H. El Haddad ◽  
T. H. Topper ◽  
T. N. Topper
Keyword(s):  
Fatigue Life ◽  
Fracture Mechanics ◽  
Intensity Factor ◽  
Crack Growth ◽  
Fatigue Cracks ◽  
Propagation Model ◽  
Actual Length ◽  
Notched Specimens ◽  
Material Condition ◽  
Length Constant

An elastic plastic fracture mechanics solution for short fatigue cracks in smooth and notched specimens is presented which admits plasticity by replacing the conventional stress term with a strain term and accounts for the propagation of very short cracks by the introduction of an effective crack length which is equal to the actual length increased by length l0, the length constant l0 is characteristic of the material and material condition and is calculated from the smooth specimen endurance limit and the long crack threshold stress intensity. Crack growth results for cracks in both elastic and plastic strain fields of notched specimens when interpreted in terms of this strain based intensity factor showed excellent agreement with elastic long crack data. This intensity factor when combined with a propagation model that includes all stages of crack growth also successfully predicted the total fatigue life of the smooth and notched specimens studied here. The predicted propagation life of elliptical and circular notched specimens is in all cases within 50 percent of the actual fatigue lives.

Effect of grain size and temperature on the yield stress of the intermetallic compound TiAl

1989 ◽  
Vol 23 (4) ◽  
pp. 467-469 ◽  
Author(s):  
V.K. Vasudevan ◽  
S.A. Court ◽  
P. Kurath ◽  
H.L. Fraser
Keyword(s):  
Grain Size ◽  
Intermetallic Compound ◽  
Yield Stress ◽  
Compound Tial
Sign in / Sign up

Export Citation Format

Share Document