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The webs such as paper, plastic film and thin metal are produced by Roll-to Roll manufacturing system, and are wound into a roll in the final process of this system. However, if the winding conditions of the web are inappropriate, the defects such as gage band, wrinkle and slippage will occur in wound roll, and then quality of products is significantly reduced. In previous studies, some analysis models of in-roll stress considering various factors, have been established to predict the defects. However, as far as authors know, there is few research regarding the gage band. In particular, the plastic films used for high functional flexible devices are being thinner, the defects can occur easily. In this paper, the in-roll stress analysis considering the web thickness variation in width direction and compressive deformation of web in the radial direction using the Hertz contact theory is presented. Moreover, optimization of winding conditions is conducted to prevent simultaneously the gage band, wrinkle and slippage. As a result, it was confirmed that the presented analysis can estimate the radial stress distribution of wound roll in the width direction. And, the effectiveness of optimized wind-up tension is verified theoretically and experimentally.

The paper presents the investigations of Ni-Al-Co-Me-based superalloy using TEM and SEM techniques. The structure and phase composition of the superalloy are investigated and the volume fractions and morphology of phases are determined in this paper. These investigations include the quantitative and qualitative analysis. It is shown that 70% compressive deformation of superalloy at 1200°C modifies its structure and phase composition.

The purpose of this paper was to confirm the influence of pulsive pressure waves on the liquid penetration into wood in the semi-opened container. Wood block sample was irradiated by the pulsive pressure waves in the semi-opened container filled with water used as a liquid. The irradiation was also performed in the closed container for the comparison. The water penetration into the sample was promoted by the pressure-wave irradiation. There was little difference in the degree of the penetration between the closed and the semi-opened containers. It was presumed from the measured hydraulic pressure that the pressure-wave energy irradiated on the sample in the closed container was higher than that in the semi-opened container. It was also presumed that the cavitation generation was promoted in the semi-opened container. This indicates that the cavitation as well as the pressure waves themselves affected the liquid penetration into wood. The compressive deformation of the sample irradiated in the semi-opened container was slightly smaller than that in the closed container. This indicates that the pulsive pressure-wave irradiation in the semi-opened container promoted the liquid penetration into wood with less compressive deformation.

Accurate prediction of springback under severe plastic deformation is necessary for the geometric error in precision forming process, in order to establish accurate model of saturated springback under bulk forming. In this paper, the springback behavior and prediction model of anisotropic face-centered cubic (FCC) crystal copper alloy under severe plastic compressive deformation (SPCD) were studied from micro-perspective and macro-perspective. From the micro-perspective, a mathematical model of springback was established based on physical and mechanics mechanisms for predicting the saturated springback of the SPCD. Subsequently, from the macro-perspective, the effects of the macro variables including stress, strain, applied load, deformed surface area, external work, etc., on the saturated springback of quasi-static SPCD were discussed, and a anisotropic springback model of FCC material for the quasi-static SPCD process in a Gaussian form was set up based on above discussion and the expression of the proposed mathematical model of springback. Furthermore, the non-quasi-static anisotropic springback model containing comprehensive effect factor and size effect factor was proposed to predict the saturated springback of copper alloy after rolling process. The results indicated that the proposed springback models based on physical mechanism and macro variables can accurately predict the saturated springback of the anisotropic copper alloy under the SPCD. By introducing comprehensive effect and size effect factors, the anisotropic springback model for the non-quasi-static SPCD process has higher accuracy in predicting the saturated springback of bulk forming process. The present study revealed the springback behavior of anisotropic FCC copper alloy, and proposed accurate prediction models of saturated springback, which are of great significance to adjust the forming process and compensate the springback error of the FCC metal material during the bulk forming process.

Incremental sheet forming (ISF) is a new promising manufacturing technology with high potential to shape complex three-dimensional parts by using a relative small tool. However, ISF is presently limited due to non-uniform thickness distribution of formed parts, especially excessive thinning on severely sloped regions. This typically leads to fracture and hence limits process formability. This paper aims to tackle this issue by developing appropriate tool path strategies for multi-pass deformation design in ISF. More specifically, two more complex shapes are designed to validate the proposed multi-pass deformation design methodology by finite element simulations and experiments. The interactions of different tool path strategies on material thinning of the final part are evaluated in terms of process formability and thickness strain distribution given the same multi-pass design. Furthermore, the movement of material points is traced to explain the material flow mechanism in multi-pass forming compared to single-pass forming. It is concluded that both deformation passes (intermediate shapes) and tool path generation strategies would influence the thickness strain distribution as well as process formability. Appropriate tool paths should be devised to further reduce material thinning and improve the process formability by taking the geometrical features of the designed part into account. Additionally, the proposed multi-pass deformation design enables sufficient material to flow into the deformed region from the outside region so as to allow a compressive deformation state to develop and steeper shapes to be formed.

This paper reveals and analyses various influence factors which cause differential settlement of high embankment in mountain area using indoor consolidation test and field loading test. In this research, the actual stress characteristics of high embankment are simplified, stability compression value of stuffing with loads under lateral restricted conditions can be measured, e-p curves and p-s curves are drawn, we can calculate compression modulus as computation criteria to estimate the settlement of high embankment. The results indicate that unconsolidated flow of high embankment is the main factor to cause differential settlement of high embankment in mountain area. As the soil consolidated, compressive deformation and the strength gradually increase, the bearing capacity of the foundation is enhanced to reduce differential settlement of the post-construction of high embankment.

In this paper, results of static loading tests on the stress transfer in mortise-tenon joints are shown. With the investigations of the experimental results, we present key requirements of a mechanical model for stress transfer in tenon joints. The model considers the discontinuity as the results of bi-axial stress state and friction by contact between tenon and mortice. Then the model can be evaluated stress transfer in the directions along fiber and perpendicular to fiber. It is necessary to recognize energy absorbing capacity and strength, inelastic mechanical model should simulate the compressive deformation inclined to the grain, the resistance of cotter and splitting. The mechanical model of main frames should be dealt with geometrically and material non-linearity incorporated with restoring force produced by rocking.

In this paper, the crushing behaviour of hexagonal honeycomb structures with finite widths and heights subjected to in-plane compressive loading is studied by using the finite element method. It is found that stress-strain curves are clasiffied roughly into two types, which include both symmetric and asymmetric modes. They are influenced by ratio of thickness of cell wall, ratio of the work-hardening, and ratio of the yield stress. In addition, it is revealed that the deformation mechanism of the honeycomb structure with the finite width and the height can be explained by the unit model proposed by Klintworth (1988), even if the effect of the work-hardening is considered.

This paper presents a testing method of interlaminar strength in the laminated direction of glass cloth reinforced plastics. To obtain the mechanical properties in the laminated direction, a method using the laminated thin wall tube specimens was proposed. The stress distribution in the specimen under tensile load was analyzed by using the finite element method. The shape of the specimen having a flat tensile stress distribution was numerically searched by varying the dimensions of specimen. The strain distribution calculated by the finite element method was confirmed by tensile tests of the laminated thin wall tube specimens. The interlaminar strength tests were conducted by subjecting the laminated specimens to axial, torsional and combined loads.The deformation in the laminated direction showed nearly elastic behavior up to the fracture of specimens except the case of compressive deformation. The interlaminar strength of the specimens under combined stress was approximately expressed by Hoffman's fracture criterion.