Vol. 6 No. 4 CONTENTS
Special issue on Material Evaluation by X-ray and Neutron Diffrcation
Special issue on Material Evaluation by X-ray and Neutron Diffrcation (Vol.6 No.4)
Preface (Vol.6 No.4)
Editorial |
Takao HANABUSA and Toru GOTO |
229 |
General Papers (Vol.6 No.4)
X-Ray Stress Measurement of TiN Thin Film with <110> Fiber Texture under External Loading |
 |
Keisuke TANAKA, Toshimasa ITO, Yoshiaki AKINIWA, Hirohisa KIMACHI and Yasuhiro MIKI |
231 |
X-Ray Stress Measurement for <110>-Oriented TiC Films |
|
Shouichi EJIRI, Juwen HE, Toshihiko SASAKI and Yukio HIROSE |
237 |
X-Ray Stress Measurement and Mechanical Properties of TiN Films Coated on Aluminum and Aluminum Alloy Substrates by Arc Ion Plating and Ion Beam Mixing |
|
Yasuhiro MIKI, Tadashi TANIGUCHI, Takao HANABUSA, Kazuya KUSAKA and Tatsuya MATSUE |
243 |
Single Crystal Elastic Constants of b-Silicon Nitride Determined by X-Ray Powder Diffraction |
|
Keisuke TANAKA, Kenji SUZUKI, Yoshihisa SAKAIDA, Hirohisa KIMACHI and Yoshiaki AKINIWA |
249 |
X-Ray Stress Measurement of Silicon Single Crystal |
|
Hiroshi SUZUKI, Koichi AKITA and Hiroshi MISAWA |
255 |
Measurement for Actual Stress Distribution by Using X-Ray Diffraction uring Rotary Bending Fatigue Test |
|
Shin-ichi OHYA, Toshitaka NAGAHAMA, Reiko KOJIMA and Yoshihiko HAGIWARA |
263 |
X-Ray Fractography Using Synchrotron Radiation
-Residual Stress Distribution just beneath Fatigue Fracture Surface- |
|
Koichi AKITA, Y. YOSHIOKA, Hiroshi SUZUKI and T. SASAKI |
269 |
Modeling and Simulation of X-Ray Stress Measurement Using PSPC as a Detector |
|
Toru GOTO and Yu GONG |
275 |
Neutron Diffraction Study of Thermal Residual Stress in Ceramic Composite |
|
Yoshiaki AKINIWA, Keisuke TANAKA, Nobuaki MINAKAWA and Yukio MORII |
281 |
Residual Stress Distribution in Carbon Steel Pipe Welded Joint Measured by Neutron Diffraction |
|
Makoto HAYASHI, Masayuki@ISHIWATA, Yukio MORII, Nobuaki Minakawa and John H. Root |
287 |
Local Stress Measurement in Notched Sapphire by Raman Microspectroscopy |
|
Yoshihisa SAKAIDA, Keisuke TANAKA and Kaori SHIRAKIHARA |
295 |
Vol.6 No.4 ABSTRACT
X-Ray Stress Measurement of TiN Thin Film with <110> Fiber Texture under External Loading
Keisuke TANAKA, Toshimasa ITO, Yoshiaki AKINIWA, Hirohisa KIMACHI and Yasuhiro MIKI
Abstract:On the bases of Reuss and Voigt models, a new X-ray method is proposed to measure the non-equi-biaxial state of stresses in thin films which have a fiber texture with <110> axis perpendicular to the film surface. The method was successfully applied to measure the stress in TiN films coated on the steel substrate by the ion-beam mixing method. The film had a strong <110> fiber texture and the initial residual stress was a compression of about -5500 Mpa. The initial part of the changes of the in-plane stresses in the film due to external tensile loading agreed well with the prediction based on elasticity. While the substrate is under uniaxial stresses, the film was in the biaxial state of stress because of the mismatch of Poisson's ratio. When the measured stress in the film becomes tension, the stress stops increasing even though the applied strain keeps increasing. This leveling of the stress was caused by cracking of the film.
Key Words:Stress measurement, X-ray method, Titanium nitride, Thin film, Fiber texture, Reuss model, Voigt model, Residual stress, Loading stress
X-Ray Stress Measurement for <110>-Oriented TiC Films
Shouichi EJIRI, Juwen HE, Toshihiko SASAKI and Yukio HIROSE
Abstract:In this study, we investigate the residual stress of titanium carbide films with the X-ray diffraction method. It is difficult to determine the stress by conventional X-ray stress measurement, I.e., the sin2y technique, because the sin2y technique requires macroscopic isotropy from the specimen but the <110> orientation is observed for our evaporated TiC films by chemical vapor deposition. Therefore, in this paper, the X-ray stress measurement for <110>-oriented films was formulated by introducing the weighted average method. The formulation showed that the relation between the stress of the specimen and the strain measured by X-ray diffraction depended on the measured diffraction planes. Then, a stress calculation was performed and discussed based on the loading experiments.
Key Words:X-ray stress measurement, Titanium carbide films, Fiber texture, Residual stress, CVD
X-Ray Stress Measurement and Mechanical Properties of TiN Films Coated on Aluminum and Aluminum Alloy Substrates by Arc Ion Plating and Ion Beam Mixing
Yasuhiro MIKI, Tadashi TANIGUCHI, Takao HANABUSA, Kazuya KUSAKA and Tatsuya MATSUE
Abstract:TiN coatings on cutting tools have greatly succeeded in prolongation of tool lives. In the present study, TiN film deposition was tried on a surface of aluminum and aluminum alloy substrates by means of an arc ion plating (AIP) method and an ion beam mixing (IBM)
method. The aim is to develop aluminum-based materials having strong wear resistance. In order to examine the hardness and residual stress of TiN films, the bias the voltage and N2 gas pressure were varied in the AIP treatment and the titanium deposition rate was changed in the IBM treatment. Vickers hardness test revealed high values (HV=1800`2400). The TiN films coated by the AIP and the IBM methods exhibited very high {111} and {110} preferred orientations, respectively. The two-exposure X-ray stress measuring method was used to measure residual stresses in the TiN film. Large compressive residual stresses of -6.3` -2.3 GPa were developed at lower N2 gas pressures for the AIP method and at higher Ti deposition rates for the IBM method. A wear experiment was also made with a ball-on-disk type wear testing machine. The depth and the width of wear traces on the surface of specimens were greatly reduced when TiN coatings were applied.
Key Words:Residual stress, Vickers hardness, Wear experiment, Aluminum and aluminum alloy substrates, Arc ion plating, Ion beam mixing
Single Crystal Elastic Constants of b-Silicon Nitride Determined by X-Ray Powder Diffraction
Keisuke TANAKA, Kenji SUZUKI, Yoshihisa SAKAIDA, Hirohisa KIMACHI and Yoshiaki AKINIWA
Abstract:The X-ray elastic constants of pressureless sintered b-silicon nitride (Si3N4), were experimentally determined for ten different diffractions by using Ka radiations of Cu, Co, Fe, Cr and V. The X-ray compliances, (1+v')/E' and v'/E' (E'= Young's modulus, v'=Poisson's ratio), change as a second power function of cos2f (f=angle between the diffraction plane normal and the c-axis of hexagonal crystal). Using the simplex method, the elastic constants of single crystals of b-silicon nitride were determined from the measured values of the X-ray compliances on the basis of the average of Voigt and Reuss models and Kroener's model, combined with the self-consistent analysis of multi-phase materials. The obtained result SHOWS a high stiffness in the c-direction of hexagonal crystals, but the degree of anisotropy is not so large as the whisker data reported by Hay et al.
Key Words:Stress measurement, X-ray method, Elastic constant, b-silicon nitride, Simplex method
X-Ray Stress Measurement of Silicon Single Crystal
Hiroshi SUZUKI, Koichi AKITA and Hiroshi MISAWA
Abstract:In X-ray stress measurement of a single crystal, the control of crystal oscillation is required in order to obtain a perfect diffraction profile. Accurate diffraction profiles can be measured by using the cy -oscillation method proposed in this study. The elasticity applied stresses in a silicon single crystal used as a material of semiconductor devices was measured using this oscillation method. Lattice strain was obtained from the peak shift of the diffraction profiles. The stress was calculated using the lattice strain of three different diffraction planes. As a result, the measured stress agreed well with the applied stress evaluated using the strain gage. Therefore, the possibility of X-ray stress measurement of a single crystal using the cy-oscillation method was confirmed. Also, the relationship between the displacement error of the specimens and the stress error was theoretically examined. It was confirmed that the effect of misalignment on X-ray stress measurement of single crystal materials is much larger than in the case of polycrystalline materials. In this study, a microscope was used in order to set the specimen.
Key Words:X-ray stress measurement, Single crystal, Diffraction profile, Semiconductor device, Lattice strain
Measurement for Actual Stress Distribution by Using X-Ray Diffraction uring Rotary Bending Fatigue Test
Shin-ichi OHYA, Toshitaka NAGAHAMA, Reiko KOJIMA and Yoshihiko HAGIWARA
Abstract:The purpose of this investigation is to detect a damage from actual stress distribution in the surface of specimen by using X-ray diffraction technique during fatigue test. An apparatus to measure the actual stress distribution along specimen circumference was fabri-cated by use of a cantilever type rotary bending fatigue machine and a stress analyzer based on single exposure technique with two posi-tion sensitive proportional counters. The authors developed a method for collecting separately the diffraction profile at each position along the circumference. Actual stress distributions at the maximum tensile applied stress were dynamically measured. As a result, the shape of the distribution was keeping stable with the increase in the number of stress cycles until crack initiation. When the crack length reached greater in size than the width of irradiation area, the actual stresses at the crack position were suddenly decreased down to 0 Mpa, and the distribution showed a V-shape. These results show that the method adopted in this study is available for detecting both the posi-tion and the period of crack initiation.
Key Words:X-ray stress analysis, Single exposure technique, Fatigue strength, Fatigue damage, Rotary bending fatigue test
X-Ray Fractography Using Synchrotron Radiation
-Residual Stress Distribution just beneath Fatigue Fracture Surface-
Koichi AKITA, Y. YOSHIOKA, Hiroshi SUZUKI and T. SASAKI
Abstract:The residual stress distributions just beneath the fatigue fracture surface were measured using synchrotron radiation of three different wavelengths having three different penetration depths. The residual stress distributions were estimated from these three diffraction data by the following process. First, a temporary residual stress distribution in the depth direction is assumed. Theoretical 2q-sin2y diagrams for each wavelength are calculated by the cosy method developed by one of the authors. The total of the differences between the theoretical and experimental values of the diffraction angle in 2q-sin2y diagrams is calculated. This total value is minimized by changing the assumed stress distribution using the quasi-Newton optimization method. Finally, the optimized 2q-sin2y diagrams for each diffraction and the detailed stress distribution are determined. The true surface residual stress is obtained from this stress distribution. No effect of the load ratio R (=Pmin /Pmax) on the residual stress of the fatigue fracture surface in low-carbon steels was observed when the sin2y method was used for stress measurement. However, it was found in this synchrotron study that the residual stress became higher with increasing R. On the basis of this, the stress intensity factor range, DK, can be estimated from the residual stress on the fatigue fracture surface.
Key Words:Fracture analysis, X-ray fractography, Synchrotron radiation, X-ray diffraction, Residual stress, Fatigue fracture surface, Stress intensity factor
Modeling and Simulation of X-Ray Stress Measurement Using PSPC as a Detector
Toru GOTO and Yu GONG
Abstract:Recently, the position sensitive proportional counter (PSPC) has been becoming popular as a detector for X-ray stress measurement. However, little information is available in the literature regarding the effects of specimen mis-setting and/or collimator misalignment on
the stress measurement. Many factors such as the stress and the X-ray diffraction broadening of the specimen, the X-ray focus size, the dimensions of the collimator, the PSPC and the goniometer are complicatedly related to the effects of specimen mis-setting and/or collimator misalignment. In this paper, a modeling of the X-ray stress measurement using a PSPC as the detector is presented enabling us to simulate the stress measurement under various conditions. In the case of Wassembly, the errors in stress measurement are illuminated under specimen mis-setting and/or collimator misalignment.
Key Words:X-ray stress measurement, Position sensitive proportional counter, Collimator, Mis-setting and misalignment, Wassembly
Neutron Diffraction Study of Thermal Residual Stress in Ceramic Composite
Yoshiaki AKINIWA, Keisuke TANAKA, Nobuaki MINAKAWA and Yukio MORII
Abstract:The residual stress in ceramic composites of alumina mixed with various volume fractions of zirconia, Al2O3/ZrO2, and of silicon carbide, Al2O3/SiC, was measured by the neutron diffraction method. The thermal re-sidual stress of each constituent phase was measured as a function of the second phase. The phase stresses were de-termined from the neutron
diffractions of ZrO2 202, Al2O3 113, Al2O3 116 , SiC 220 and SiC 311. In Al2O3/ZrO2 composites, the residual stress in the alumina phase was compression and that in the zirconia phase was tension. On the other hand, in Al2O3/SiC composites, the residual stress in the alumina phase was tension, and increased linearly with the silicon carbide volume fraction. The residual stresses were introduced by the mismatch of the coefficient of
thermal expansion. The change of the residual stress with volume fraction of the second phase agreed well with the theoretical prediction based on Eshelby's inclusion model.
Key Words:Residual stress, Neutron stress measurement, X-ray stress measurement, Ceramic composite, Phase stress, Inclusion model
Residual Stress Distribution in Carbon Steel Pipe Welded Joint Measured by Neutron Diffraction
Makoto HAYASHI, Masayuki@ISHIWATA, Yukio MORII, Nobuaki Minakawa and John H. Root
Abstract:In order to estimate crack growth behavior of fatigue and stress corrosion cracking in pipes, the residual stress distribution near the pipe weld region has to be measured through the wall thickness. Since the penetration depth of neutron is deep enough to pass through the thick pipe wall, the neutron diffraction technique for the residual stress measurement is effective for this purpose. At the first step the residual stress distribution near the weld region in a butt-welded carbon steel pipe was measured by the neutron diffraction. Significant stresses extended only to a distance of 30mm from the center of the weld. The major tensile stresses occurred in the hoop direction in the fusion and heat affected zones of the weldment, and they attained a level greater than 200MPa through the thickness. While the axial residual stress at the inside surface was 50MPa, the stress at the outside surface was -100MPa. The comparison of residual stress distributions measured by the neutron diffraction, the X-ray diffraction and the strain gauge method reveals that the neutron diffraction is the most effective for measuring the residual stress inside the structural components.
Key Words:Neutron diffraction, Residual stress, Welded pipe joint, X-ray diffraction, Strain gauge method
Local Stress Measurement in Notched Sapphire by Raman Microspectroscopy
Yoshihisa SAKAIDA, Keisuke TANAKA and Kaori SHIRAKIHARA
Abstract:A new system of Raman microspectroscopy was developed to measure the residual stress in a local area with about 2 mm diameter in ceramics. The system was applied to a single crystal sapphire in order to evaluate the capability of the system. The shift of two Raman spectra, 645 and 418 cm-1, of A1g mode was proportional to the lattice strain, e33, along the c-axis of trigonal crystals. The proportional constant was larger for 418 cm-1 than for 645 cm-1 spectrum. The distributions of loading strains due to four-point bending were measured across the minimum ligament of single-edge-notched specimens by scanning the focused Ar+ laser beam. The strain concentration near the notch root was successfully detected by Raman microspectroscopy. The measured distributions of strains agreed very well with the results of a finite element analysis. The developed system of Raman microspectroscopy was applicable to the strain measurement in the area having a steep gradient as observed near the crack tip in ceramics.
Key Words:Local stress measurement, Raman microspectroscopy, Sapphire, Finite element method