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The propagation of stress waves and the concentration of dynamic stress in tapered lap adhesive joints with impact loading were investigated analytically and experimentally. Stress distribution and time variation of stress and strain in the joints under tensile impact loading were calculated using FEM, considering viscoelastic properties of the adhesive resin. Impact tests on the adhesive joints of aluminum alloy were conducted. Calculated results agreed with experimental results. The effects of taper length on the concentration of stress and strain were examined by comparing the calculated results with the experimental results. An increase in taper length is an effective way to reduce the concentration of stress and strain in adhesive lap joints under impact loading.

The dynamic strength of an adhesively bonded joint was investigated experimentally. Strength of an adhesive layer and an interface between adhesive and adherend under combined impact loading was measured using the clamped Hopkinson bar method. A tuber butt adhesive joint was used for the experiment. The strength of the adhesive joint was determined by measuring strain transmitted in the transmission tube of the specimen. The dynamic strength of the adhesive layer was greater than the static strength under tensile and shear loads. The time duration to fracture, however, was very short.

This paper discusses the dynamic strain and stress distribution of adhesively bonded joints having different configurations. The selected configurations are tapered lap and scarf joints. The dynamic deformation of the joints under impact loading is calculated using the finite element method. The calculated strains are compared with the experimentally measured dynamic strains. The bending effect for the tapered lap joints are more remarkable than those in the scarf joints when the joints are subjected to impact loading. Stress waves propagate in a complicated manner due to the bending effect and the reflection of the waves for the tapered lap joints; however the waves propagate smoothly for the scarf joints. The dynamic stress in the adhesive layer increases for the tapered lap joints with increasing in time, but the change in dynamic stress with respect to time is negligible for the scarf joints.

Propagation of stress wave and concentration of dynamic stress in tapered lap adhesive joints under impact loading were investigated analytically and experimentally. Stress distribution and time variation of stress and strain in the joints under tensile impact loading were calculated using F.E.M. considering viscoelastic properties of adhesive resin. Impact tests on the adhesive joints of aluminum alloy were conducted. Calculated results agreed with experimental results. Effects of taper length on the concentration of stress and strain were examined by comparing the calculated results with the experimental results. An increase in taper length is effective to reduce the concentrations of stress and strain in adhesive lap joints under impact loading.

レーザーアブレーション(LA)/ICP-AESによる金属の直接分析法において,水溶液標準試料を用いた定量法を検討した.ICPトーチに四重管型を用い,その補助試料導入口から合成標準溶液を導入することにより検量線を作成した.四重管トーチの試料導入位置の違いによる感度差は内標準法で低減でき,低沸点元素の選択蒸発の影響はレーザーのせん(尖)頭出力を土げることにより低減できた.又,ICPへの溶媒導人の有無は発光強度に著しい影響を与えるため,LA法での測定中においても蒸留水を並列に導入することにした.本法の適用性を低合金鋼,Ti合金,Al合金の分析において調べたところ,低合金鋼中のCu,Cr,Mn,Ni,Mo,Vを誤差26%以内の正確さで定量できた。又,Ti及びAl合金の分析における誤差は,40%以内であった.

Inductively coupled plasma mass spectrometry using a laser ablation technique has been developed for the analysis of small inclusions of fused silica. A Q-switched pulsed Nd: YAG laser is fired at interesting sites of sample pieces with sizes of 10-40mm. Ablated particles were introduced directly into the ICP. Preablation with the laser pulses was effective in removing the surface contamination; thus, 1-min preablation could be conducted at interesting sites before data acquisition. The intensity ratios of interesting elements to matrix element with corrections using the relative sensitivity factors obtained by a solution introduction method provide some semi-quantitative data concerning the samples. The established procedure has been applied to the analysis of black inclusions of fused silica. The results have indicated that the major constituent of the inclusions was Fe (oxides).

The metal vapor evaporated from molten steel was solidified to yield fine particles. Using this technique, the resulting particles were introduced into an atomic absorption spectrometric instrument with an electrically heated absorption cell which utilized Ar as the carrier gas. The majorirty of the particles were of round shape and their diameters were less than 1 μm. The temperature of the molten steel and the absorption cell had a great influence on the sensitivity. As the absorption cell temperature increased up to 1200°C, the manganese absorbance became substantially higher. The use of the iron absorbance as the internal standard was effective in correcting the variation in the amount of fine particles introduced into the absorption cell.

レーザーアブレーション(LA)/ICP-MS法の深さ方向の分析特性を調べた.検討には,膜厚1.5μmのSnめっき鋼板を用い,レーザー光のデフォーカスの影響や出力,発振周波数の影響について調べた.Snめっき鋼板については,焦点位置から10mm程度レンズに近づけてデフォーカスさせたときが最適で,200mJ以下の低出力,1Hz以下の低発振周波数でμmレベルの深さ分解能が得られた.又,サンプリング速度は対象となる物質により異なり,検討した7種の金属のうちCu以外の金属については,サンプリング速度と沸点が逆比例の関係にあった.LA/ICP-MSの応用として,TiN膜及び塗装鋼板の深さ方向分析を試みた.

高周波燃焼/電量滴定法による高純度鉄中の微量硫黄定量方法について検討した.すなわち燃焼ガス流量の影響,助燃材の影響,試料量の影響及び硫黄の二酸化硫黄としての回収率を求めて分析条件を決定した.高純度鉄中の硫黄を本法で定量したところ1ppm程度の硫黄が精度よく分析可能であった.又,検出下限は0.23μgであった.更に他分析方法と分析精度も比較した.

A flow injection (FI) technique has been applied to the trace analysis of metal samples using inductively coupled plasma mass spectrometry (ICP-MS). Parameters such as carrier flow rate, injection volume and sample concentration has a great influence on the sensitivity, precision and analysis time of the FI/ICP-MS. A small volume (240μl) of nickel-base alloy solutions containing up to 0.75% (m/v) was introduced into an ICP-MS instrument by the flow of carrier solution. The optimized procedure was applied to the determination of Tl, Pb and Bi in standard nickel-base alloys of the National Institute of Standards and Technology. The result was compared with that of the continuous sample nebulization method. The FI method gave improved precision as well as high sensitivity. The precision ranged from 2.0 to 8.2 (RSD, %) for the elements containing 0.25-11.7ppm. Detection limits were 0.001-0.04ppm.

エチレングリコール抽出・導電率測定法による製鋼スラグ中の遊離酸化カルシウムの迅速定量法について検討した.カルシウムと同時に抽出される鉄及びマンガンが導電率測定時に影響を与えるため,その補正方法を決定した.すなわち,抽出された金属(鉄及びマンガン)量は490nmにおける吸光度から決定できることから,これを補正法として用いて,分析法を確立した.本法による分析結果とAASによる分析結果はよく一致した.又,分析精度は2.5～3.3%(相対標準偏差)であった.

An atomic absorption spectrometric system was examined to clarify manganese evaporation behavior from molten steel. The system was based on direct atomic absorption measurement of the manganese vapor evaporated from the molten steel at 1600±10°C. The results showed that the absorbance of manganese depended on the manganese concentration in the molten steel. The iron absorbance was used effectively to correct the amounts of evaporated vapor. The absorbance ratio of manganese to iron was in proportion to the manganese concentration.

Un systeme d'ablation par laser YAG a ete developpe pour l'analyse directe des aciers par spectrometrie ICP-AES (le laser permet d'obtenir des particules finies de taille

There are many methods for measuring FT-IR spectra, for example, transmission, diffuse reflection, attenuated total reflection and so on. It is said that the transmission method is the most reliable method for qualitative and quantitative analysis of FT-IR spectra. The spectra of highly scattering samples such as coals or amorphous silicon powders measured by the transmission method, however, have large backgrounds with small relevant absorption peaks. Therefore, we investigated measuring methods for reducing the background itself. As a result, using a highly scattering 1R filter, we could clearly distinguish absorption peaks of amorphous silicon powders that were not found in IR spectrum measured by the normal transmission method. Our highly scattering filter is composed of fine Csl powders(

水酸化ベリリウム共沈分離/モリブドリン酸青吸光光度法によるタングステン含有合金中のリン定量方法を検討した.ニッケル,クロム,コバルト,ジルコニウムなどを含む合成試料を用いて各元素の影響を調査した.ニッケル,コバルト,はEDTAでマスキングすることで,クロムは二塩化二酸化クロムとして揮散することで良好な結果が得られた.ただし,ジルコニウムが1%以上と同時にタングステンが2%以上存在する場合はその影響を受ける.又,1-ペンタノールを抽出溶媒とする溶媒抽出法も検討した.それぞれの定量下限はモリブドリン酸青吸光光度法では20ppm,溶媒抽出法では1ppmであった.

A new interelement correction method has been developed for the X-ray fluorescent determination of chromium in high-alloy steels and nickel-base alloys. The calibration equation which was derived from the JIS (Japanese Industrial Standards) model is applicable over wide ranges of compositions by preparation of only Fe-Cr binary standards.

The results of a preliminary study on direct analysis of solid metals and nonconductive samples by inductively coupled plasma mass spectrometry (ICP-MS) are described. The aerosols ablated from solid samples by a ruby laser are introduced into an inductively coupled plasma, with detection of the resulting ions by a mass spectrometer. With conventional solution introduction, polyatomic species from mineral acids and solvents prevent the accurate determination of some trace analytes. However, using laser ablation, these background peaks are greatly reduced. The relative sensitivity factors for the laser ablation method are seen to vary from unity, with volatile elements such as Pb and Bi being more sensitive. Detection limits of rare-earth elements, Th and U in silicate rocks are excellent (0.02-0.9ppm at the effective integrating time of 1.4s), being better than those of the examined elements in steel (1.7-29ppm at the effective integrating time of 0.6s).

鉄鋼試料中の副・微量成分の迅速定量法として,ルビーレーザーによる固体試料の直接サンプリング/ICP-AES法を検討した.レーザー照射により生成したエアロゾル試料の搬送条件及びICP測定条件について最適化した後,鉄鋼試料の分析に本法を適用した.Si,Mn,P,Ni,Cr,Cu,Mo,V,Ti,Co,Nb,B,As,Snについて,正確さの良い検量線が得られた.鉄鋼試料の日常分析法であるスパーク発光分光法と比較し,検量線の直線性が良く,ダイナミックレンジが広い利点がある.しかし,分析精度はスパーク発光分光法より劣る元素が多い.

XRF法による鉄鋼分析において,Sc管球の特性を調べ,従来から用いられているRh管球との比較を行った.Sc管球から放射される連続X線強度はRh管球の約40%程度であり,このためScのK線より短波長側に吸収端を持つ元素に関してはRh管球のほうが高感度であった.一方,ScのK線が励起に関与するS,P,Si,Al,Cの定量においては,Rh管球に比べ感度・精度共に向上した.又,特にSc管球による向上が著しいCの定量について高速度工具鋼を試料として用い検討を行ったところ,共存元素によるスペクトル線の重なりが認められた.しかし,JIS法による重なり補正を行うことにより定量精度・正確さ共に良好な結果が得られた.

The method for determining free silicon in sintered Si3N4 by laser Raman spectrometry has been studied. In this study, it was found that the amount of free silicon can be determined from the Raman peak intensity ratio I. 521cm-1/I. 206cm-1, in which the peak of 521cm-1 is assigned to free silicon and that of 206cm-1, to skeleton vibration of β-Si3N4. The results obtained by using this method are as follows:(1) The increase in sintering temperature and time tends to increase the amount of free silicon.(2) The variation of free silicon content at the surface part from place to place is greater than that at the inside part.This method makes it possible to measure the amount of free silicon in β-Si3N4 easily, and possibly gives instructive information such as the condition for avoiding precipitation of free silicon.

粉体試料の迅速分析法として,ルビーレーザーによる固体試料の直接サンプリング/ICP-AES法を確立した.粉体試料は加圧成形によりペレットとするか(ブリケット法),あるいは,四ホウ酸ナトリウムと融解してガラスビードとして(ガラスビード法),レーザー照射に供した.鉄鋼精錬スラグの分析に本法を適用したところ,ブリケット法では,今回検討したSi, Al, Mg, Fe, Mn, Ti, Pについて良好な精度と正確さが得られた.又,ガラスビード法はブリケット法に比し,迅速性・適用性は劣るものの,主成分の定量において精度・正確さを向上することができる.

鉄鋼試料を硫酸と過酸化水素で分解し,発生する二酸化炭素を2-アミノエタノールを含むジメチルホルムアミド溶液に吸収させた後,テトラブチルアンモニウムヒドロキシドで滴定する方法を検討した.酸分解によって二酸化炭素と同時に各種の炭化水素が発生する.これは鉄と酸との反応によって生ずる水素(プロトン)によって炭素が水素化されて生ずるものと考えられる.共存する硫黄が高値を示す原因となるが,活性二酸化マンガンによって除去可能であった.炭素5μgまでは良好な精度で分析可能であった.日本鉄鋼標準試料を分析した結果,相対標準偏差1%前後で定量できた.

Because they are composed of a variety of chemical components, pitches are possessed of highly scattering properties. Therefore, the spectra of pitches obtained by FT-IR have large backgrounds, and the backgrounds have a detrimental influence on the accuracy of analysis. Recently, the diffuse reflection method has been widely used for analyzing pitches, although it has been pointed out that the method has some problems; for example, diffuse reflection cannot obtain very sharp absorption peaks. In this paper, new dilution materials are developed and proposed that allow one to obtain fine spectra of pitches. With the use of our dilution materials, the shapes of absorption peaks become more sharp, the intensities of the peaks increase considerably, and the backgrounds of those spectra are reduced to a large extent. The quality of the spectra of the pitches is considerably improved. Our method may prove to be a solution for dealing with the problem posed by backgrounds, which have heretofore seriously affected accuracy in the analysis of spectra.

The accuracy in quantitative and qualitative analysis of IR spectra of coals by the transmission method has been limited. This is because the IR transmission spectra of coals possess large background interferences. In this note, we report a method for reducing background, thus allowing an increase in the precision of quantitative analysis by the IR transmission method. In our observation, an IR scattering filter proved to reduce the background remarkably.