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In this paper, it is found that the preferential growth of secondary {117} facets of Bi24O31Br10 into dominant facets would lead to higher photocatalytic activity, although the original main {213} facet has a stronger molecular oxygen adsorption ability, which illustrates that the charge separation efficiency induced by dominant/secondary facet control plays a more important role than that of O2 adsorptive performance in improving activity.

Gas atomization uses a high-speed gas flow to impact alloy melt and crush it into small droplets. During this process, the kinetic energy of the high-speed gas flow is transformed into the surface energy of small droplets, and the droplets are dragged and cooled by the gas. In this study, a FeNiCrBSiC alloy was used to investigate the motion and solidification behavior of alloy droplets during gas atomization. A mathematical model of the cooling and solidification process of droplets is modified and used. The initial velocity of the droplets attributed to the breakup by the high-speed gas flow is considered a factor. The results suggest that the velocity difference between the droplet and the gas is appearing to be smaller, indicating that droplets are more likely to collide with each other; as the velocity difference between the droplet and the gas becomes smaller, the heat transfer coefficient decreases. Thus, the solidification process of the droplet needs a longer flight distance; the relation between the cooling rate and the particle size was determined from measured data and empirical formula and model validation was performed.

The purpose of this investigation was to evaluate the microstructure, high-temperature oxidation behaviour, and hardness of a seal coating under controlled exposures at 750 °C with different exposure times. The results reveal that the main phases in the coating are Ni, FeNi3, and hexagonal BN, with α-Al2O3 peaks appearing after 2-h oxidation. As the exposure time increases, the diffraction peak intensity of α-Al2O3 begins to decrease and Cr2O3 peaks appear after 200 h. After 1000 h, Cr2O3 becomes dominant with only small amounts of α-Al2O3 remaining. The high-temperature oxidation process of the coating includes three stages: the fast stage, transition stage, and slow stage. The oxidation rate is constant in each stage, and in the fast stage and slow stages with values of 7.59 × 10−4 and 8.37 × 10−5 mg2·cm−4·s−1, respectively. Initially, α-Al2O3 forms near the pores in the coating, followed by the formation of Cr2O3. As the exposure time increases, oxidation penetrates into the interior of the coating along phase boundaries to form island-shaped inner oxide layers with high concentrations of Cr, Ni, and Fe. Additionally, hardness increases with increasing oxide percentage.

This paper investigates the intensity noise and pulse oscillation characteristics of an InAs/GaAs quantum dot laser epitaxially grown on germanium. We show that the relative intensity noise of the free-running laser generally decreases with increasing pump current, and the minimum value reaches down to about $-$ 126 dB/Hz. The intensity noise is hardly affected by the optical feedback, unless there is a resonance or pulse oscillation in the noise spectrum. The laser pumped at a high current is more sensitive to the optical feedback. Interestingly, it is found that the free-running Ge-based quantum dot laser generates self-sustained pulse oscillations with one period or two periods upon the pump current, without incorporating saturable absorbers. This behavior is valuable for both self-generation of photonic microwaves and for understanding nonlinear dynamics of semiconductor lasers.

In order to study the process and characteristic of the fragments in the warhead with one end cap under full constraint condition, we established a cylindrical casing with two end caps which one of them was fully constrained using the simulation analysis. The result showed that the fragmentation of cylindrical casing with one end full constrained has its own characteristic. The Mach stem was generated when the detonation wave propagated to the fully constrained end cap under the condition of one end detonation, working on unreactive explosives and causing the nearby fragment subjected to nearly 2.5 times the normal pressure to obtain a higher speed. The cylindrical casing first ruptured at the contact surface with the fully constrained end, and then at the end cover of the initiating end, and then the rupture extends to the whole cylindrical casing. The detonation products started to leak out from the rupture. driving fragments to fly, and forming two dense flying areas. The analysis of this paper can provide a reference for the optimal design of this kind of warhead.

The impact of impurities on the microstructure and thermal shock resistance of YSZ TBCs was investigated. ZrO2-7.5wt%Y2O3 (7.5YSZ) coatings of 5 spices of compositions (4 of them were doped with one type of impurity, namely, Al2O3, Fe2O3, SiO2 and TiO2, and the other was not doped) were manufactured by APS. Thermal shock tests of these TBCs were carried out at 1100 °C, and the samples were quenched in cold water in the temperature range from 20 to 25°C. The microstructure evolution and phase analysis were performed before and after the thermal shock tests by scanning electron microscope (SEM) and X-ray diffractometer (XRD). The results showed that the thermal shock lifetime of YSZ TBCs doped with impurities was obviously reduced compared to that of no-impurity TBCs. Additionally, the differences in the microstructure and phases of YSZ TBCs were ascertained and the elements distribution was tested by Energy Dispersive Spectrometer (EDS) and Energy Dispersive X-Ray Spectroscopy (EDX).

InAs/GaAs quantum dot (QD) lasers monolithically grown on Ge or Si are a promising method to achieve low cost, large scale, and high yield optical sources for photonic integrated circuits [1]. This work shows that a free-running Ge-based QD laser can output periodic pulse oscillations with one, two and three periods, without incorporating saturable absorber or employing any external perturbations [2,3]. The QD laser under study was epitaxially grown on a 4-inch Ge-wafer by the gas-source molecular beam epitaxy, and the active region consists of five stacked dot-in-well layers [4]. The wafer was fabricated into a ridge-waveguide laser with a ridge width of 4.0 μm and a cavity length of 4.4 mm. The laser shows a lasing threshold of 60 mA at 20 °C, and the lasing peak is at 1213 nm. Figure 1(a) shows that the relative intensity noise (RIN) of the Ge-based laser pumped at 80 mA exhibits a common resonance with continuous-wave output. However, the resonance of the laser pumped at 160 mA does not become overdamped, but evolves into pulse oscillations with a high and sharp peak. Figure 1(b) shows the resonance frequency and the damping factor extracted from the RIN spectra. The resonance frequency increases with the pump current from 0.4 GHz at 80 mA up to 1.1 GHz at 170 mA, whereas the damping factor declines from 4.0 GHz down to 0.03 GHz. The damping reduction confirms the onset of peculiar pulsing dynamics for pump currents above 140 mA.

This work experimentally investigates the optical feedback sensitivity of InAs/GaAs quantum dot (Qdot) lasers epitaxially grown on Ge substrate. In comparison with a Qdot laser on GaAs substrate with identical epilayer and cavity structures, the Ge-based laser is found to exhibit lower sensitivity to the optical feedback, although it has a higher epitaxial defect density. Theoretical analysis proves that the high defect density strongly increases the damping factor while slightly reduces the linewidth broadening factor, which lead to high tolerance to the optical feedback. This work suggests the high potential of Qdot lasers on Ge for isolator-free operation in photonic integrated circuits.

Silver nanowires–epoxy composites were prepared via cryomilling dispersion and hot-press forming process. The microstructure of the silver nanowires was studied by SEM. Dependence of dielectric properties of the composites on volume fraction of silver nanowires and frequency was investigated RF impedance material analyzer. The percolation threshold of the composites was 0.16, the value of the dielectric constant of the composite was as high as 100.

Barium ferrite micro/nanofibers were successfully prepared via the electrospinning by using dimethyl formamide (DMF) as the solvent, poly vinyl pyrrolidone (PVP) as the spinning auxiliaries and iron nitrate and barium nitrate as raw materials. The effect of poly vinyl pyrrolidone on the structure, morphology, magnetic and microwave absorbing properties were investigated by scanning electron microscope (SEM), X-ray diffraction analysis (XRD), vibration sample magnetometer (VSM) and vector network analyzer (VNA). XRD patterns of the samples confirmed that when the additive content of PVP was up to 10%, (wt%) pure barium ferrite fibers formed under the condition of the same heat treatment. Also, the FE-SEM images showed that the morphology of the fibers improved with the increase of PVP content. Moreover, the VSM results demonstrated that the saturation magnetization can reach 54.7 emu/g when the PVP dosage is 14% (wt%) in the precursor solution.

In this paper, the microstructure of laser cladding layer was studied under two laser conditions. The microstructure of laser cladding layer was characterized as directional rapid solidification. On the premise of forming a good metallurgical bond between the coating and the matrix, higher laser energy density was harmful to refine the coating structure and reduce the microhardness of the coating.

This work demonstrates that the relative intensity noise of Ge-based epitaxial InAs quantum dot lasers are weakly sensitive to the temperature, while it is more sensitive to the optical feedback at higher bias currents.

To improve gas turbine performance, it is essential to decrease back flow gases in the high-temperature combustion region of turbo machine by reducing the shroud/rotor gap. An abradable seal coating will function effectively. Therefore, it is significant to identify and characterize the main wear mechanisms occurring on turbo machinery seals. A high temperature and speed test rig has been developed by BGRIMM for testing the AlSi–hBN abradable seal coating and Ti-6Al-4V dummy blade. Impact velocities between 150 and 300m·s-1 and incursion rates between 5.0 and 480 μm·s-1 have been applied. It was found that incursion rate has a greater impact on the wear mechanism of the AlSi–hBN coating, with tests at low incursion rate showing a obvious grooving and little micro-rupture, whereas tests at high incursion rate showing significant cutting and adhesion. The present work also shown that tests at low incursion rate related to a higher IDR, which means that blade suffered a serious wear. The investigation together with SEM and XRD analysis on the coating revealed both wear and adhesion occurred at the end of the test.

Growing semiconductor laser sources on silicon is a crucial but challenging technology for developing photonic integrated circuits (PICs). InAs/GaAs quantum dot (Qdot) lasers have successfully circumvented the mismatch problem between III–V materials and Ge or Si, and have demonstrated efficient laser emission. In this paper, we review dynamical characteristics of Qdot lasers epitaxially grown on Ge or Si, in comparison with those of Qdot lasers on native GaAs substrate. We discuss properties of linewidth broadening factor, laser noise and its sensitivity to optical feedback, intensity modulation, as well as mode locking operation. The investigation of these dynamical characteristics is beneficial for guiding the design of PICs in optical communications and optical computations.

The free standing NiCrAlY and NiCoCrAlY coating samples were prepared by HVOF. The cyclic oxidation resistance of the coatings was evaluated and the coating surface morphology was investigated by SEM. The MCrAlY coating CTE was tested. The results show that the NiCoCrAlY coating exhibits better oxidation resistance than the NiCrAlY coating and the difference in MCrAlY CTE curve shape is considered as the main reason.

The bioactivity of two plant extract mixtures on Lasioderma serricorne adults were investigated. As biomateriasls, the two plant extract mixtures had potent contact toxicity and fumigant toxicity against L. serricorne adults, which significantly increased with increasing treatment dosages. The toxicity of plant extract mixtureⅡ was stronger than that of plant extract mixture. For the contact toxicity, the LD50 values of plant extract mixtureⅠ and plant extract mixture Ⅱ were 2.89 and 1.37 µL/cm2, respectively. For the fumigant toxicity, the LD50 values of plant extract mixtureⅠ and plant extract mixture Ⅱ were 284.42 and 82.95 µL/L air, respectively.

Nd2Fe14B/-Fe nanocomposite permanent magnet contains the hard and soft magnetic phases, Nd2Fe14B and -Fe respectively. An exchange coupling effect exists between the two magnetic phases. The effect of alloying element Nb on its nanostructure and properties have been studied. Adding Nb to the alloy is effective to refine grains, a relatively small grain size causes a high intrinsic coercivity, remanence and therefore a high maximum energy product, (BH)max. MFM (Magnetic Force Microscope) was used to observe the magnetic micro-domain structure in the nanophase alloys. The length of the magnetic contrast shows a significant dependence on the microstructure and phase constitution, and the longer length is correspond with the larger exchange coupling effect between the soft and hard magnetic phases.

We report the relative intensity noise (RIN) characteristics of an InAs quantum dot (Qdot) laser epitaxially grown on the Ge substrate. It is found that the minimum RIN of the Ge-based Qdot laser is around −120 dB/Hz, which is 15 dB higher than that of a native GaAs-based Qdot laser with the same layer structure. The higher RIN in the Ge-based laser can be attributed to the high-density epitaxial defects of threading dislocations and antiphase domain boundaries.

By means of finite element method which is based on the conventional theory of mechanism-based strain gradient plasticity, cohesive interface model is used to study the intergranular fracture in polycrystalline metals with nanoscale and ultra-fine grains. A systematical study on the overall strength and ductility of polycrystalline aggregates which depend on both grain interiors and grain boundaries for different grain sizes is performed. The results show that the overall strength and ductility of polycrystalline aggregates with nanoscale and ultra-fine grains are strongly related to the competition of grain boundaries deformation with that in grain interiors. Finally, the deformation and failure behavior of nanocrystalline nickel are described by using the computational model.

The limitation of the currently available thermal management method has put an ever serious challenge for computer chip designers. A liquid metal with low melting point around room temperature was recently identified as a powerful coolant of driving heat away because of its superior thermo-physical properties and the unique ability to be driven efficiently by a completely silent electromagnetic pump. However, the adoption of gallium, one of the best candidates as metal coolant so far, may cause serious corrosion to the structure materials and subsequently affect the performance or even dangerous running of the cooling system. To address this emerging critical issue, here the compatibility of gallium with four typical metal substrates (6063 Aluminum-Alloy, T2 Copper-Alloy, Anodic Coloring 6063 Aluminum-Alloy and 1Cr18Ni9 Stainless Steel) was comprehensively investigated in order to better understand the corrosion mechanisms and help find out the most suitable structure material for making a liquid metal cooling device. To grasp in detail the dynamic corrosion behavior, an image acquisition and contrasting method was developed. Moreover, corrosion morphology analyses were performed by means of scanning electron microscope (SEM). The chemical compositions of the corroded layers were evaluated using energy dispersive spectrometry (EDS). According to the experiments, it was found that, the corrosion of the 6063 Aluminum-Alloy was rather evident and serious under the temperature range for chip cooling. The loose corrosion product will not only have no protection for the inner substrate, but also accelerate the corrosion process. Compared to the 6063 Aluminum-Alloy, T2 Copper-Alloy showed a slow and general corrosion, but part of the corrosion product can shed from the substrate, which will accelerate corrosion action and may block the flowing channel. Anodic Coloring 6063 Aluminum-Alloy and 1Cr18Ni9 Stainless Steel were found to have excellent corrosion resistance among these four specimens. No evident corrosion phenomena were found under the examination of SEM and EDS when exposed for 30 days at the temperature of 60°C, which suggests their suitability as structure materials for the flow of liquid metal. However, as for the Anodic Coloring 6063 Aluminum-Alloy, surface treatment and protection are of vital importance. The present study is of significance for making a liquid metal chip cooling device which can actually be used in the future computer industry.

A fine-grained magnesium alloy AZ31was obtained through equal channel angular pressing (ECAP).Mechanical properties and the microstructures after deformation under tension and compression were investigated. The tensile strength, compressive strength and the elongation to failure of the fine-grained AZ31 are enhanced due to the reduction of grain size. The compressive ultimate strain (CUS) of the fine-grained AZ31 magnesium alloy is lower than that of the initial state due to the formation of shear bands during compression. The ECAP processed AZ31 magnesium alloy exhibited no tension/compression asymmetry in yielding.

The mechanical behaviors of the ceramic particle-reinforced metal matrix composites are modeled based on the conventional theory of mechanism-based strain gradient plasticity presented by Huang et al. Two cases of interface features with and without the effects of interface cracking will be analyzed, respectively. Through comparing the result based on the interface cracking model with experimental result, the effectiveness of the present model can be evaluated. Simultaneously, the length parameters included in the strain gradient plasticity theory can be obtained.

TiN coating was deposited on TC11 titanium alloy by arc ion plating technique and reactive direct current (D.C.) magnetron sputtering technique. The phases of TiN coating were determined by XRD technique. The surface morphology and hardness of TC11 alloy and TiN coating were analyzed by SEM and Micro-hardness Detector measurements, respectively. The tribological behaviors of reciprocating sliding for two TiN coatings which prepared by different PVD technologies (magnetron sputtering and ion plating) were studied on UMT wear tester. The results showed that wear properties of TC11 alloy were considerably improved by two TiN coatings.

Due to its high specific stiffness and strength, good damage tolerance capabilities, and good fatigue resistance with respect to the traditional materials, metal matrix composite materials (MMCs) have attracted much research interests in recent years. It is known that interface debonding plays an important role in the thermo-mechanical behavior of the MMCs. In the present study, the effect of interface debonding on the mechanical properties of MMCs has been studied by a new periodic unit cell model, the multi-particle cubic (MPC) model, which is proposed with the consideration of the inhomogeneous structures within the MMCs. The representative cell is constructed by several randomly distributed elastic spheres, matrix material and interfacial region with the perfect bonding initially. And the onset of damage was assumed to follow a maximum normal stress criterion. The simulated results agree well with the experimental results. It is found that with the decrease of interfacial strength, the degradation of the composite resulted from the initiation and propagation of interfacial damage becomes severe. Damage evolution of the interface is further investigated with the increase of plastic strain. In additions, the predictions from the MPC model have also been compared with those from the single particle cubic (SPC) model.

In this paper, the variety behavior in spraying process of nanoparticle agglomerated ZrO2 −8% Y2O3 (YSZ)powder by air plasma spraying(APS) is studied. The morphology, microscopic structure and phase structure of sprayed powder were analyzed by SEM and XRD. The result indicates that the agglomerated particle surface happens to melt and be crystallization by APS sprayed, and the grain size is 0.5∼1.5μm. The molten zone thickness increases gradually as the particle diameter reduces. The particle inside still keeps nanoparticle structure. The phase structure accords with the powder before spraying.

An experimental verification is reported on the early predicting index of agglomeration in bubbling fluidized bed. Coarse quartz sand, which has the same density but larger diameter than the bed material, was used to simulate the initial agglomerated particle. Wigner distribution was used to analyze the pressure fluctuation of the tested bed, and the average amplitude of local domain frequency (LDF) and local peak weighted average frequency (LPWA) under different operating conditions were measured and compared. The results showed that the LDF is sensitive to the agglomeration phenomena and had quick response to the incipient agglomeration in fluidized beds. It can be concluded from the results that these two parameters could be taken as the characteristic indexes to the agglomeration in fluidized beds.

Polarizing beam splitter (PBS) is a critical optical component in projection display system because PBS performance greatly influences the contrast and brightness of the system. PBS performance is usually measured by spectrophotometer after coating and cementing, but the measured result cannot represent the actual performance in practice because people usually change the incident angle in one plane (horizontal plane) and do not consider the other plane (vertical plane). Geometrical polarization rotation occurring at reduced F-number influences the measuring precision of s-polarization transmittance (Ts) and p-polarization reflectance (Rp). A more accurate and practical way to measure the performance of broadband, wide-angle PBS is presented in this paper.

Progressive damage along a kink band plays an important role for damage characterization of fiber-reinforced materials under compression. We approach this prob lem from a set of homogenized field equations which set up the criterion of initial surface instability. Further progression of the bifurcated kink bands into the composite blocks is formulated under damage induced bridge model, within the framework of J integral.

Effective heat dissipation is of great importance in many engineering fields. In this paper, we investigated a newly emerging method to significantly improve the cooling capability of micro channel devices, through implementing liquid metal with low melting point as the powerful coolant. A series of experiments with different working fluids and volume flow were performed, and the different cooling effects between liquid metal and water were compared. In order to better evaluate the cooling capability of liquid metal based micro channel cooling device, the hydrodynamic and heat transfer theory involved was discussed. The results indicated that, when the system operated in a relatively high velocity, micro channel cooling devices with liquid metal as coolant could produce higher convective heat transfer coefficient compared to those with traditional cooling fluids. And under the same pump power, not only the thermal resistance of liquid metal based micro channel could be much smaller, but also the coolant volume flow could be decreased. What is more, the liquid metal can be driven by a highly efficient electromagnetic pump without any noise. Therefore, more compact and energy-saving micro channel cooling devices with better cooling capability may come into reality. This new method is rather practical, and is expected to be important for realizing an extremely high heat dissipation rate.Copyright © 2009 by ASME

In the present work, a series of [Fe80Ni20—O/SiO2]n multilayer thin films is fabricated using a reactive magnetron sputtering equipment. The thickness of SiO2 interlayer is fixed at 3 nm, while the thickness values of Fe80Ni20—O magnetic films range from 10 nm to 30 nm. All films present obvious in-plane uniaxial magnetic anisotropy. With increasing the Fe80Ni20—O layer thickness, the saturation magnetization increases slightly and the coercivity becomes larger due to the enlarged grain size, which could weaken the soft magnetic property. The results of high frequency magnetic permeability characterization show that films with thin magnetic layer are more suitable for practical applications. When the thickness of Fe80Ni20—O layer is 10 nm, the multilayer film exhibits the most comprehensive high-frequency magnetic property with a real permeability of 300 in gigahertz range.

Based on the 2D-PC wave multilayer film structure, a method to broaden the bandwidth of polarization beam splitter is proposed, which is composed of two different thickness periodic film stacks. Combined with the evaluation function of polarization splitting characteristic, the particle swarm optimization method is employed to design the optimal structural parameters. A broadband and compact polarization beam splitter is acquired, in which the center wavelength is 565 nm and its working range has achieved 220 nm with the average extinction ratio over 30 dB. In addition, by using the finite difference time domain method, the band structure and transmission spectrum of the wave-structure multilayer film are calculated, the angle sensitivity of the structure is investigated in detail. And we also study the electromagnetic field in the wavy-structure. Simulation results prove that the structure composed of the two different thickness periodic film stacks can avoid the discontinuity of bandgap, and PSO method can accelerate the convergence of the optimization algorithm and extend the bandwidth effectively.

A novel design of reflective color filters based on a two-dimensional subwavelength grating structure is proposed, which exhibits an incident angle independent property with unpolarized incident light in the visible range. By using rigorous coupled-wave analysis method, the effects of the grating period, the groove depth and the size of the structure on the reflectance spectrum are investigated in detail. The structural parameters of the gratings are optimized, and a color filter with high angular tolerance is achieved. Simulation result shows that the maximal reflectance is 56% at 424 nm with a bandwidth of 45 nm, and that the grating can almost keep its reflectance, bandwidth and the peak position at the incident angle up to about 60° under unpolarized incident light. The peak position of the color filter can be tuned from 400 nm to 520 nm by changing structural parameters of the gratings, and keep its incident angle-independent property.

According to the requirements for design and manufacture, we choose double-chirped method for designing the initial structure of the chirped coatings, and analyze the dependencs of reflectivity and group delay dispersion on the parameters of coatings such as the double-chirped modulation factor and the the proportion of double-chirped layers on the total thin film stack. Further more, we establish their optimal values. Based on the analysis, a chirped mirror pair, whose reflectivity is more than 99.5% and average group delay dispersion is -40 fs2 with a residual ripple of less than 20 fs2 in a wavelength range of 600 nm-1050 nm, is demonstrated, which is to be used in the Ti: Sapphire femtosecond laser system for dispersion compensation.

Optical properties, stress and microstructure of Nb2O5 thin films prepared by ion beam sputtering (IBS) are investigated, and the effects of assist ion beam energy and ion current on characteristics of Nb2O5 thin films are systematically discussed. The results show that with different parameters of assisted ion source, the refractive index changes from 2.310 to 2.276 and residual stress varies from -281MPa to -152 MPa. The extinction coefficient of Nb2O5 can be under 10-4, and the surface is very smooth in an optimum deposition condition. Thin films deposited by IBS exhibit better optical properties and microstructures than those deposited by ion assisted deposition (IAD).

A Gires-Tournois(GT) mirror with a group delay dispersion (GDD) of -60 fs2 in one reflection was designed according to the requirement of dispersion compensation in the Ti-sapphire femtosecond laser system. It was manufactured by ion assisted deposition combined with the optical monitoring in transmission. The reflectance of the mirror was measured by a spectrophometer working in the range from 650 nm to 950 nm with a resolution of 1 nm. The results were consistent with the design. Furthermore, a home-made white light interferometry system was employed to test the reflection GDD and the result also agreed well with the design. The experimental GDD oscillation was less than ± 20 fs2. The GT mirror was applied in the Ti-sapphire femtosecond laser system and a good clamping result was obtained. Finally a 29 fs ultra-short pulse was acquired.

HfO2 films were prepared by electron beam evaporation on K9 glass. The residual stresse was measured by viewing the substrate deflection using ZYGO interferometer. The influences of deposition rate and oxygen partial pressure on the residual stress were studied. The results show that all the residual stresses are tensile stresses. The packing density of films increases while the residual stress decreases with the increasing deposition rates and the decreasing oxygen partial pressure. The microstructure of the HfO2 films was inspected by X-ray diffraction （XRD）. The relationship between the stress and the microstructure was also discussed.

Films deposited at high temperature are subjected to thermal stresses in cooling down, duc to the mismatch of thermal expansion between substrate and film materials, which tends to peel off the film from the substrate. The purpose of the present work is to search the effect of thickness, Young's modulus and thermal expansion of the films on the delamination of the films. The results are helpful in reducing the possibility of the peeling of the films.

Electric field modeling of nodular defects is performed to investigate the interaction between defective multilayer coatings and Gaussian profile laser beam. Light intensity is significantly enhanced as large as 6 times within the nodular defects. Different geometries of defects irradiated by laser beams at 0 to 40 deg incident laser angles are analyzed. Nodules with large but shallow seeds, or irradiation of 40 deg p-polarized laser beam, tends to produce the greatest enhancement effect.