bluuebunny/crossref_metadata_2025_split huggingface dataset:
SHORT CRACK GROWTH BEHAVIOUR UNDER VARIABLE AMPLITUDE LOADING OF SHOT PEENED SURFACES
Authors: De Los Rios E. R. , Mercier P. , El‐Sehily B. M. 
Published: April 2007

Abstract— The effect of variable amplitude loading on the initiation and propagation of fatigue cracks from shot peened and unpeened surfaces was investigated. The results confirm the well‐known effect of shot peening, i.e. the increase of fatigue life in comparative tests under constant amplitude loading. Shot peening increases the time to crack initiation and also decreases crack propagation rate, particularly in the earlier stages of growth.Variable amplitude tests were of various kinds: (i) half‐life at one stress level, followed by testing at the second stress level until failure, (ii) sequence loading at two stress levels, and (iii) a different number of overload cycles (1, 10, 100) following a given number of base amplitude cycles.The results of the two amplitude tests showed different behaviour depending on whether the first half‐life cycles were of higher or lower stress levels. These results are explained in terms of crack density and crack coalescence. The extent of damage accumulation during block loading depends on the stress levels employed. The benefits of shot peening are compromised by high stress levels.Results from the overload tests showed that the interpretation of results is not straight forward. A combination of the theories of crack retardation and microstructural‐fracture mechanics seems a necessary prerequisite in an explanation of the resultant behaviour.
ENERGY DAMAGE SUMMATION METHODS FOR CRACK INITIATION AND GROWTH DURING BLOCK LOADING IN HIGH‐TEMPERATURE LOW‐CYCLE FATIGUE
Authors: Skelton R. P. , Rees C. J. , Webster G. A. 
Published: April 2007

Abstract— Strain‐controlled total endurance tests have been carried out on smooth specimens of 2¼Cr‐1Mo steel at 550°C in continuous cycling, and also using interspersed blocks of “major” and “minor” cycling. Similar low‐cycle fatigue crack growth tests were also carried out on cylindrical specimens of ½CrMoV steel containing a 0.2 mm deep starter defect using interspersed blocks of “major”, “intermediate” and “minor” cycling, their order being changed in separate tests.Damage summation in the smooth specimen tests at failure was found to be less than unity (irrespective of the failure criterion) when Miner's rule was employed, and the results are compared with limited previous data. Damage was also summed on an energy‐expended basis and this was found to be (i) independent of strain range, and (ii) independent of cycle type (i.e. continuous loading or block loading). The nearer the chosen failure criterion to crack initiation, the closer was the agreement in accumulated energies.Similarly, in the crack growth tests, the number of complete loops to “failure” (10% load drop) was independent of block order over a wide range of applied strain ranges, but was affected by the number of cycles in each block. However, the energy criterion was again able to rationalise all the data.
PREDICTING THE EFFECTS OF CRACK TIP CONSTRAINT ON MATERIAL RESISTANCE CURVES USING DUCTILE DAMAGE THEORY
Authors: Burstow M. C. , Howard I. C. 
Published: April 2007

Abstract— In recent years much interest has been focused on the geometry dependence of the resistance to stable ductile crack growth of engineering materials, and in particular, in explaining this in terms of “constraint” effects. This paper describes the results of work using the Rousselier ductile damage model in finite element studies to simulate the growth and coalescence of voids, and hence the mechanics of ductile crack growth, to predict the effect of constraint on resistance to fracture. Using the modified boundary layer solution, where constraint is controlled by the application of remote displacements, it was possible to simulate resistance curves for different constraint conditions. This has produced a “net” of resistance curves, within which the curve for any specimen geometry can be found from a knowledge of the crack tip constraint for that specimen. This has been tested by comparing the results with those obtained from two specimens for which the constraint conditions are known. Good agreement has been achieved.The results show that, although constraint has very little effect on conditions at the crack tip at initiation of crack growth, beyond that constraint plays an important part in defining the resistance curve. For low constraint geometries there is a very large loss in crack tip constraint which results in a large increase in the slope of the resistance curve. On the other hand, high constraint geometries exhibit very little dependence on crack tip constraint.
A STUDY ON STRENGTH CHARACTERISTICS OF Si3N4 COIL SPRINGS
Authors: Sato S. , Taguchi K. , Adachi R. , Nakatani M. 
Published: April 2007

Abstract—Coil springs made of silicon nitride (Si3N4), which has higher strength and heat resistance than other ceramics, have recently been developed. By examining the range of strengths and the heat resistance of the coil springs, it is shown that the coil springs can be used at temperatures up to 1000°C. We derive an equation to calculate the effective volumes of coil springs and examine the influence of size on the strength of coil springs. In addition, using a process zone size failure criterion, proof tests were conducted and analysed. The results show that the mean strength of coil springs decreases with increasing effective volume. Therefore the strength of coil springs can be estimated from the value of the effective volume, and this relationship can be applied in design calculations. Furthermore, by conducting proof tests, coil springs that have relatively large defects can be eliminated and so only highly reliable coil springs can be placed in service.
A MODEL TO PREDICT THE FATIGUE LIFE OF FIBRE‐REINFORCED TITANIUM MATRIX COMPOSITES UNDER CONSTANT AMPLITUDE LOADING
Authors: De Los Rios E. R. , Rodopoulos C. A. , Yates J. R. 
Published: April 2007

Abstract—A model based on micro‐mechanical concepts has been developed for predicting fatigue crack growth in titanium alloy matrix composites. In terms of the model, the crack system is composed of three zones: the crack, the plastic zone and the fibre. Crack tip plasticity is constrained by the fibres and remains so until certain conditions are met. The condition for crack propagation is that fibre constraint is overcome when the stress at the location of the fibre ahead of the crack tip attains a critical level required for debonding. Crack tip plasticity then increases and the crack is able to propagate round the fibre. The debonding stress is calculated using the shear lag model from values of interfacial shear strength and embedded fibre length published in the literature.If the fibres in the crack wake remain unbroken, friction stresses on the crack flanks are generated, as a result of the matrix sliding along the fibres. The friction stresses (known as the bridging effect) shield the crack tip from the remote stress, reducing the crack growth relative to that of the matrix alone. The bridging stress is calculated by adding together the friction stresses, at each fibre row bridging the crack, which are assumed to be a function of crack opening displacement and sliding distance at each row. The friction stresses at each fibre row will increase as the crack propagates further until a critical level for fibre failure is reached. Fibre failure is modelled through Weibull statistics and published experimental results. Fibre failure will reduce the bridging effect and increase the crack propagation rate.Calculated fatigue lives and crack propagation rates are compared with experimental results for three different materials (32% SCS6/Ti‐15‐3, 32% and 38% SCS6/Ti‐6‐4) subjected to mode I fatigue loading. The good agreement shown by these comparisons demonstrates the applicability of the model to predict the fatigue damage in Ti‐based MMCs.
A FRACTURE MODEL TO STUDY THE EFFECT OF SPECIMEN SIZE ON DYNAMIC ENERGY RELEASE RATES
Authors: Dear J. P. 
Published: April 2007

Abstract—The aim of this research was to simulate the ability of a material to transfer energy to the tip of a rapidly propagating crack when varying the specimen geometry and other factors. For this study, a distributed mass spring model was used which could be hosted on a Personal Computer (PC) of the type now available in most fracture laboratories to capture and process experimental data. The distributed mass spring model was chosen because it was easy to reconfigure for different studies. Also, it could produce the required data in the same format as more powerful FE models and at a quality not dramatically less than FE models. A most useful feature of the model was the good visibility of the fracture processes it was able to represent.
J‐Q MODEL FOR PREDICTING FRACTURE IN THE DUCTILE‐BRITTLE TRANSITION
Authors: Landes J. D. 
Published: April 2007

Abstract—A model is proposed to predict cleavage failure of precracked bodies in the transition region for steels. It is based on the concept that the failure of a weak link triggers the failure of the entire body. The model is similar to that originally proposed by Heerens et al. which assumes that the weak link has a given level of stress labeled the cleavage stress needed to cause failure. This weak link is located at some characteristic but variable distance from the crack tip. The variation in distance from the crack tip to the weak link causes variation in the transition fracture toughness. The crack tip stress is given by the J‐Q model of O'Dowd and Shih where Q characterizes the constraint level in the body.Given a set of input data, that is fracture toughness from a given specimen geometry at a known temperature, toughness values can be predicted from these inputs at a different temperature where the yield stress is known or for a different size or geometry where Q is known. The model is applied here for two steels; a DIN 20MnMoNi55 steel and a CrMoV steel. For the first steel fracture toughness values measured on compact specimens are used to predict cleavage fracture throughout the transition for the same geometry. For the second steel the transition trend is predicted for the same compact geometry. The results show that the model is good for predicting the sudden end of the transition that is often observed but does not predict the lower shelf or early transition very well. This is a region where a weak link mechanism may not be operating.SUMMARYA model is proposed to predict the cleavage fracture toughness in the transition for steels. It is based on a weak link failure concept and a crack tip stress distribution that is influenced by the constraint level. The model uses measured fracture toughness data to predict a distance from the crack tip to the weak link. This distance is a variable that is used to account for all of the variability in the fracture toughness. For a new temperature or geometry the toughness can be predicted by assuming that the cleavage stress is fixed and the material has the same range of weak link distances. The magnitude of the crack tip stresses can change due to a change in yield stress or constraint.The model was used to predict the toughness trend in the transition and the end of the transition. It was applied to two steels, a 20MnMoNi55 steel and a CrMoV steel. For the 20MnMoNi55 steel the transition trend and the end of the transition that were predicted by the model compared well with experimental results. For the CrMoV steel the interesting part was that the lower shelf region of the transition was not predicted well. The prediction from the model overestimated the measured fracture toughness values. This suggests, as was previously believed, that a weak link mechanism may not operate near the lower shelf part of the transition. The model could also be used to predict the toughness for a new geometry such as a component model geometry. That will be reported in a later work.
QUANTITATIVE FRACTOGRAPHIC ANALYSES OF FATIGUE CRACK GROWTH IN LONGERONS OF IN‐SERVICE HELICOPTER ROTOR‐BLADES
Authors: Shaniavski A. A. 
Published: April 2007

Abstract— An analysis is made of striation spacing measurements as observed on fatigue crack surfaces of specimens and longerons of helicopter rotor‐blades made from the aluminium alloy AVT. It is shown that, for the combined cyclic tensile stresses at various R‐ratios and static rotation angles, α, striation spacings were controlled by an equivalent intensity factor Ke=K1F(α, R). Values of the F(α) for Ri= const were computed.The crack growth life in terms of the number of flights and stress equivalents were computed for various longeron sections of the helicopter rotor‐blades which had failed in service.SUMMARY AND CONCLUSIONS(1) A fatigue striation spacing analysis was made from measurements on AVT Al‐alloy specimens tested in air under combined cyclic tension and static‐rotation loads at various a‐angles of rotation, and stress ratios, R. Fractographic analyses have shown similarities in terms of striation spacing formation in the investigated range of α‐angles and R ratios.(2) The similarity in the fatigue fracture mechanisms attested to the possibility of characterizing the striation spacing formation by a unified kinetic diagram via a Ke= K1F(α, R) approach for different α‐angles and R ratios. The function F(α, R) was determined and it can be used to calculate the tensile stress equivalent according to values of σi measurements taken from components broken in tests or in service.(3) It was a longeron of the rotor‐blade of helicopters manufactured from AVT Al‐alloy broken in service and tested cyclically that were investigated fractographically. An analysis of the formation of striations and their spacing has shown similarities with the investigated longerons fatigued in tests and in service. The crack growth life versus number of flights and stress equivalent was calculated according to values of the σi measurements.(4) It was shown that a fatigue crack will not nucleate in longerons in service if the depth of defects on the external surface have a size less than 0.3 mm. The stress for tested longerons is near to the calculated equivalent for longerons that failed in service.
A THERMAL ACTIVATION APPROACH TO THE CRACK RESISTANCE OF STEELS
Authors: Saidov G. I. 
Published: April 2007

Abstract— In this study, the relation between fracture toughness and mechanical properties, grain structure, temperature and strain rate is analysed on the basis of a thermo‐activation analysis of the plastic deformation of metals.As a result of the study, the relationships obtained are of sufficient accuracy in relation to standard cracked samples of many steels.These relations can be used as a tool when designing new alloys which have a strong resistance to crack growth.This study is limited to temperatures in the range 0 ≤ T ≤ 0.2Tm and BCC metals.
Economic Effects of Multinational Accounting Diversity
Authors: Choi Frederick D. S. 
Published: April 2007

AbstractThe purpose of this paper is to whet the appetite of accounting researchers by providing a menu of research issues in accounting and auditing that merit scholarly attention and which appear suitable for publication in JIFMA. Especially needed are inquiries that examine the economic impacts of accounting differences in a world economy characterized by unconstrained capital flows, far‐flung multinational operations and financial decisions which are made within the context of organizational complexity with diverse practices and traditions of economic behavior. The research questions that need to be addressed are substantive and will soon dwarf national inquiries in importance as the trend toward a world economy continues.
Voluntary Corporate Disclosure by Swedish Companies
Authors: Cooke T. E. 
Published: April 2007

AbstractSweden is of interest because of the rapid growth in the Stockholm Stock Exchange and because of the country's disproportionate number of multi‐national enterprises. This paper reports on the extent of voluntary disclosure in the corporate annual reports of unlisted and listed Swedish companies. A wide‐ranging definition of voluntary disclosure is adopted because of the flexibility of approach accepted in Sweden. This should not be construed that Swedish accounting is largely unregulated, rather it reflects a problem of interpretation of what constitutes generally accepted accounting principles in Sweden. In addition, the paper assesses whether there is a significant association between a number of independent variables and the extent of disclosure.
Accounting Information and Investment Risk Perception in Japan*
Authors: Ferris K. , Hiramatsu K. , Kimoto K. 
Published: April 2007

AbstractThis paper investigates the issue of whether financial reports appear to convey information on risk on a consistent basis across international capital markets. Data collected from a sample of Japanese financial analysts are compared to previously reported data from U.S. analysts. The results indicate that traditional accounting measures of risk explain substantial variation in the average risk perceptions of financial analysts in both the U.S. and Japan; however, while accounting risk measures were found to explain significant variation in ex post beta for the U.S. sample, this was not found to be the case for the Japanese sample. The implications of these cross‐national differences and similarities are discussed.
Managerial Perceptions of the Net Benefits of Foreign Listing: Canadian Evidence
Authors: Mittoo Usha R. 
Published: April 2007

AbstractThis study provides some insights into managerial perceptions of the costs, benefits, and net benefits of foreign listing through a survey of Canadian firms that have listed their securities on the foreign exchanges in the U.S. and U.K. Access to foreign capital markets and increased stock marketability are perceived to be the major benefits. The SEC reporting and compliance requirements are cited as the major costs of foreign listings. Overall, benefits are perceived to outweigh costs although not significandy. Managerial perceptions of positive net benefits are strongly linked to the levels of trading volume in their firm's stock on foreign exchanges. This study is useful for managers contemplating foreign listings. Our findings indicate that the listing decision requires careful scrutiny in terms of potential costs and benefits which may depend on many firm specific factors. Firms conducting most of their business abroad and issuing a greater percentage of equity abroad are likely to have a greater appeal for foreign investors irrespective of their size and industry. While multiple listings on foreign exchanges may not imply higher foreign trading volumes, fewer domestic exchange listings are associated with higher foreign trading volumes.
The Economic Determinants of the Home Country Bias in Investors' Portfolios: A Survey
Authors: Uppal Raman 
Published: April 2007

AbstractIn this article, we survey the international portfolio choice literature to investigate why investors choose to bias their portfolios towards domestic equity, even though there are significant gains to diversifying internationally. We focus on three potential explanations. First, we consider if the high proportion of domestic assets in investors' portfolios can be explained by their desire to hedge home inflation. While the models of Krugman (1981), Sercu (1980), Adler and Dumas (1983), and Stulz (1981a, 1983) suggest that this is the case, the model in Uppal (1993) shows that this is true only when relative risk aversion is less than one. Second, we consider the prevailing institutional barriers to foreign investment to see if they are sufficiently large to explain the bias observed in investors' portfolios. Halliday (1989) reports that there are few constraints on investing in foreign stock markets. This is especially true when investing in the markets of developed countries. Even when restrictions exist, they are usually not binding. Third, we consider the models of Black (1974) and Stulz (1981b) to see if transactions costs for investing abroad and taxes on income from foreign assets can explain the home equity bias. Cooper and Kaplanis (1986, 1991) and French and Porterba (1991) estimate that the taxes required to explain the observed bias are much larger than those investors actually face. We conclude that it is unlikely that these three factors are significant enough to explain the degree of the bias in portfolios that is observed empirically.
The Influence of Culture on Organizational Design and Planning and Control in Australia and the United States Compared with Singapore and Hong Kong
Authors: Harrison Graeme L. , McKinnon Jill L. , Panchapakesan Sarala , Leung Mitzi 
Published: April 2007

AbstractThis study draws on the national cultural dimensions of power distance, individualism, and Confucian dynamism to predict and explain differences in philosophies for, and approaches to organizational design and management planning and control systems in Australia and the US, representing Anglo‐American nations, and Singapore and Hong Kong, representing the ‘five dragons' of East Asia. Data were gathered by survey questionnaires mailed to senior accounting and finance executives in 800 organizations.The results were largely as predicted and, in general, provide support for the importance of national culture in influencing organizational design and management planning and control systems. In particular, the cultural values of Anglo‐American society relative to East Asian society are associated with a greater emphasis on decentralization and responsibility centres in organizational design, and a greater emphasis on quantitative and analytical techniques in planning and control. By contrast, the cultural values of East Asian society are associated with a greater emphasis on long‐term planning and on group centred decision‐making. The results are important to managers in global organizations who need to understand the cultural bases of observed differences in organizational and management planning and control practices in Anglo‐American and East Asian nations.
Voluntary Disclosure in the Annual Reports of New Zealand Companies
Authors: Hossain M. , Perera M. H. B. , Rahman A. R. 
Published: April 2007

AbstractNew Zealand is currently experiencing a liberal and competitive economic environment which has led to a greater investment interest in corporate securities. Likewise, New Zealand firms are also developing strategies to attract investors, for example, through voluntary disclosure of information. Therefore, the level of information voluntarily disclosed by New Zealand companies is of interest to prospective investors. The purpose of this study is to examine empirically the relationship between five firm‐specific characteristics and the general level of accounting information voluntarily disclosed by companies listed on New Zealand Stock Exchange (NZSE). In this study the a priori expectations are based on agency theory. The five firm‐specific characteristics examined are: firm size, leverage, assets‐in‐place, type of auditor, and foreign listing status. The results obtained from cross‐sectional regression show that firm size, foreign listing status and leverage are significantly related to the extent of voluntary disclosure. In contrast assets‐in‐place and type of auditor are not significant explanatory variables. A study of this type would be of particular relevance to accounting policy makers because, inter alia, it helps them in (a) understanding corporate disclosure behaviour, (b) explaining why firms adopt certain disclosure strategies, and (c) developing a coherent and acceptable set of mandatory disclosure requirements.